{"transactions":[{"id":705921,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":18814,"kind":"person","name":"TANG KEVIN","position":1,"cik":"0001178579","reported_name":"TANG KEVIN","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":18815,"kind":"organization","name":"TANG CAPITAL MANAGEMENT LLC","position":2,"cik":"0001232621","reported_name":"TANG CAPITAL MANAGEMENT LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-07-21T01:10:00.000Z","date":"2026-07-17","kind":"purchase","planned":false,"acquired":true,"shares":50945,"price":3.52,"value":179326.4,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares were purchased in multiple transactions at prices ranging from $3.46 to $3.55."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Tang Capital Partners, LP (\"TCP\") beneficially owns 1,668,554 shares, Tang Capital Partners International, LP (\"TCPI\") beneficially owns 2,212,803 shares, Tang Capital Partners III, Inc. (\"TCP III\") beneficially owns 1,668,539 shares, and Tang Capital Partners IV, Inc. (\"TCP IV\") beneficially owns 1,531,049 shares. Kevin Tang is the sole manager of Tang Capital Management, LLC, which is the general partner of TCP and TCPI. Kevin Tang is the sole director and Chief Executive Officer of TCP III and TCP IV, which are indirectly wholly owned by TCP. Mr. Tang has a pecuniary interest in the shares beneficially held by TCP, TCPI, TCP III and TCP IV."}],"balance_after":7080945,"source":{"system":"sec-edgar","filing":"0001178579-26-000016","document":"form4-07212026_010750.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1178579/000117857926000016/form4-07212026_010750.xml","form_type":"4"}},{"id":705920,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":18814,"kind":"person","name":"TANG KEVIN","position":1,"cik":"0001178579","reported_name":"TANG KEVIN","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":18815,"kind":"organization","name":"TANG CAPITAL MANAGEMENT LLC","position":2,"cik":"0001232621","reported_name":"TANG CAPITAL MANAGEMENT LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-07-21T01:10:00.000Z","date":"2026-07-16","kind":"purchase","planned":false,"acquired":true,"shares":116671,"price":3.56,"value":415348.76,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The prices reported are weighted-average prices. These shares were purchased in multiple transactions at prices ranging from $3.50 to $3.60. The Reporting Persons undertake to provide the Issuer, any security holder of the Issuer or the SEC staff, upon request, all information regarding the number of shares purchased at each price within the ranges set forth in Footnotes 1 and 3."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Tang Capital Partners, LP (\"TCP\") beneficially owns 1,668,554 shares, Tang Capital Partners International, LP (\"TCPI\") beneficially owns 2,212,803 shares, Tang Capital Partners III, Inc. (\"TCP III\") beneficially owns 1,668,539 shares, and Tang Capital Partners IV, Inc. (\"TCP IV\") beneficially owns 1,531,049 shares. Kevin Tang is the sole manager of Tang Capital Management, LLC, which is the general partner of TCP and TCPI. Kevin Tang is the sole director and Chief Executive Officer of TCP III and TCP IV, which are indirectly wholly owned by TCP. Mr. Tang has a pecuniary interest in the shares beneficially held by TCP, TCPI, TCP III and TCP IV."}],"balance_after":7030000,"source":{"system":"sec-edgar","filing":"0001178579-26-000016","document":"form4-07212026_010750.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1178579/000117857926000016/form4-07212026_010750.xml","form_type":"4"}},{"id":709230,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":18814,"kind":"person","name":"TANG KEVIN","position":1,"cik":"0001178579","reported_name":"TANG KEVIN","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":18815,"kind":"organization","name":"TANG CAPITAL MANAGEMENT LLC","position":2,"cik":"0001232621","reported_name":"TANG CAPITAL MANAGEMENT LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-07-15T23:50:22.000Z","date":"2026-07-15","kind":"purchase","planned":false,"acquired":true,"shares":107377,"price":3.56,"value":382262.12,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F5","text":"These shares were purchased in multiple transactions at prices ranging from $3.50 to $3.60."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Tang Capital Partners, LP (\"TCP\") beneficially owns 1,630,142 shares, Tang Capital Partners International, LP (\"TCPI\") beneficially owns 2,160,423 shares, Tang Capital Partners III, Inc. (\"TCP III\") beneficially owns 1,630,127 shares, and Tang Capital Partners IV, Inc. (\"TCP IV\") beneficially owns 1,492,637 shares. Kevin Tang is the sole manager of Tang Capital Management, LLC, which is the general partner of TCP and TCPI. Kevin Tang is the sole director and Chief Executive Officer of TCP III and TCP IV, which are indirectly wholly owned by TCP. Mr. Tang has a pecuniary interest in the shares beneficially held by TCP, TCPI, TCP III and TCP IV."}],"balance_after":6913329,"source":{"system":"sec-edgar","filing":"0001178579-26-000014","document":"form4-07152026_110717.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1178579/000117857926000014/form4-07152026_110717.xml","form_type":"4"}},{"id":709229,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":18814,"kind":"person","name":"TANG KEVIN","position":1,"cik":"0001178579","reported_name":"TANG KEVIN","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":18815,"kind":"organization","name":"TANG CAPITAL MANAGEMENT LLC","position":2,"cik":"0001232621","reported_name":"TANG CAPITAL MANAGEMENT LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-07-15T23:50:22.000Z","date":"2026-07-14","kind":"purchase","planned":false,"acquired":true,"shares":75952,"price":3.58,"value":271908.16,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"These shares were purchased in multiple transactions at prices ranging from $3.53 to $3.60."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Tang Capital Partners, LP (\"TCP\") beneficially owns 1,630,142 shares, Tang Capital Partners International, LP (\"TCPI\") beneficially owns 2,160,423 shares, Tang Capital Partners III, Inc. (\"TCP III\") beneficially owns 1,630,127 shares, and Tang Capital Partners IV, Inc. (\"TCP IV\") beneficially owns 1,492,637 shares. Kevin Tang is the sole manager of Tang Capital Management, LLC, which is the general partner of TCP and TCPI. Kevin Tang is the sole director and Chief Executive Officer of TCP III and TCP IV, which are indirectly wholly owned by TCP. Mr. Tang has a pecuniary interest in the shares beneficially held by TCP, TCPI, TCP III and TCP IV."}],"balance_after":6805952,"source":{"system":"sec-edgar","filing":"0001178579-26-000014","document":"form4-07152026_110717.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1178579/000117857926000014/form4-07152026_110717.xml","form_type":"4"}},{"id":709228,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":18814,"kind":"person","name":"TANG KEVIN","position":1,"cik":"0001178579","reported_name":"TANG KEVIN","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":18815,"kind":"organization","name":"TANG CAPITAL MANAGEMENT LLC","position":2,"cik":"0001232621","reported_name":"TANG CAPITAL MANAGEMENT LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-07-15T23:50:22.000Z","date":"2026-07-14","kind":"purchase","planned":false,"acquired":true,"shares":53651,"price":3.56,"value":190997.56,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares were purchased in multiple transactions at prices ranging from $3.54 to $3.60."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Tang Capital Partners, LP (\"TCP\") beneficially owns 1,630,142 shares, Tang Capital Partners International, LP (\"TCPI\") beneficially owns 2,160,423 shares, Tang Capital Partners III, Inc. (\"TCP III\") beneficially owns 1,630,127 shares, and Tang Capital Partners IV, Inc. (\"TCP IV\") beneficially owns 1,492,637 shares. Kevin Tang is the sole manager of Tang Capital Management, LLC, which is the general partner of TCP and TCPI. Kevin Tang is the sole director and Chief Executive Officer of TCP III and TCP IV, which are indirectly wholly owned by TCP. Mr. Tang has a pecuniary interest in the shares beneficially held by TCP, TCPI, TCP III and TCP IV."}],"balance_after":6730000,"source":{"system":"sec-edgar","filing":"0001178579-26-000014","document":"form4-07152026_110717.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1178579/000117857926000014/form4-07152026_110717.xml","form_type":"4"}},{"id":709227,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":18814,"kind":"person","name":"TANG KEVIN","position":1,"cik":"0001178579","reported_name":"TANG KEVIN","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":18815,"kind":"organization","name":"TANG CAPITAL MANAGEMENT LLC","position":2,"cik":"0001232621","reported_name":"TANG CAPITAL MANAGEMENT LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-07-15T23:50:22.000Z","date":"2026-07-13","kind":"purchase","planned":false,"acquired":true,"shares":12966,"price":3.54,"value":45899.64,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The prices reported are weighted-average prices. These shares were purchased in multiple transactions at prices ranging from $3.54 to $3.55. The Reporting Persons undertake to provide the Issuer, any security holder of the Issuer or the SEC staff, upon request, all information regarding the number of shares purchased at each price within the ranges set forth in Footnotes 1 and 3 through 5."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Tang Capital Partners, LP (\"TCP\") beneficially owns 1,630,142 shares, Tang Capital Partners International, LP (\"TCPI\") beneficially owns 2,160,423 shares, Tang Capital Partners III, Inc. (\"TCP III\") beneficially owns 1,630,127 shares, and Tang Capital Partners IV, Inc. (\"TCP IV\") beneficially owns 1,492,637 shares. Kevin Tang is the sole manager of Tang Capital Management, LLC, which is the general partner of TCP and TCPI. Kevin Tang is the sole director and Chief Executive Officer of TCP III and TCP IV, which are indirectly wholly owned by TCP. Mr. Tang has a pecuniary interest in the shares beneficially held by TCP, TCPI, TCP III and TCP IV."}],"balance_after":6676349,"source":{"system":"sec-edgar","filing":"0001178579-26-000014","document":"form4-07152026_110717.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1178579/000117857926000014/form4-07152026_110717.xml","form_type":"4"}},{"id":719687,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":33367,"kind":"person","name":"Banks Sonja","position":1,"cik":"0001896415","reported_name":"Banks Sonja","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:33.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294703","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1896415/000119312526294703/ownership.xml","form_type":"4"}},{"id":717184,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":29690,"kind":"person","name":"Dorton Katina","position":1,"cik":"0001617541","reported_name":"Dorton Katina","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:31.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294699","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1617541/000119312526294699/ownership.xml","form_type":"4"}},{"id":717888,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:26.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294697","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000119312526294697/ownership.xml","form_type":"4"}},{"id":717129,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32613,"kind":"person","name":"Haviland Kate","position":1,"cik":"0001663022","reported_name":"Haviland Kate","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:14.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294692","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1663022/000119312526294692/ownership.xml","form_type":"4"}},{"id":717204,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32645,"kind":"person","name":"King Rachel K.","position":1,"cik":"0001589712","reported_name":"King Rachel K.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:11.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294691","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1589712/000119312526294691/ownership.xml","form_type":"4"}},{"id":717592,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32747,"kind":"person","name":"GERAGHTY JAMES A","position":1,"cik":"0001239746","reported_name":"GERAGHTY JAMES A","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:10.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294690","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1239746/000119312526294690/ownership.xml","form_type":"4"}},{"id":717973,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32860,"kind":"person","name":"Hill Colin","position":1,"cik":"0001673192","reported_name":"Hill Colin","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:07.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294683","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1673192/000119312526294683/ownership.xml","form_type":"4"}},{"id":718132,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32908,"kind":"person","name":"Ezekowitz Alan","position":1,"cik":"0001780209","reported_name":"Ezekowitz Alan","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-07-02T20:30:06.000Z","date":"2026-06-30","kind":"grant","planned":false,"acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 30, 2026 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":32000,"derivative":{"exercise_price":3.66,"expiration_date":"2036-06-29","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001193125-26-294680","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1780209/000119312526294680/ownership.xml","form_type":"4"}},{"id":722816,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32908,"kind":"person","name":"Ezekowitz Alan","position":1,"cik":"0001780209","reported_name":"Ezekowitz Alan","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-06-30T20:30:02.000Z","date":"2026-06-26","kind":"sale","planned":false,"acquired":false,"shares":18000,"price":3.6452,"value":65613.6,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 27, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $3.555 to $3.82, inclusive. The reporting person undertakes to provide to Fulcrum Therapeutics, Inc., any security holder of Fulcrum Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (2) to this Form 4."}],"balance_after":10927,"source":{"system":"sec-edgar","filing":"0001193125-26-290622","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1780209/000119312526290622/ownership.xml","form_type":"4"}},{"id":795255,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":50223,"kind":"person","name":"Lehrer-Graiwer Joshua","position":1,"cik":"0001789673","reported_name":"Lehrer-Graiwer Joshua","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-05-01T20:15:07.000Z","date":"2026-04-23","kind":"grant","planned":false,"acquired":true,"shares":64000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on April 23, 2026 and is scheduled to vest in equal monthly installments until April 23, 2029, subject to continued service."}],"balance_after":64000,"derivative":{"exercise_price":8.08,"expiration_date":"2036-04-22","underlying":"Common Stock","underlying_shares":64000},"source":{"system":"sec-edgar","filing":"0001193125-26-201468","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000119312526201468/ownership.xml","form_type":"4"}},{"id":919370,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-02-04T21:15:06.000Z","date":"2026-01-02","kind":"sale","planned":false,"acquired":false,"shares":15000,"price":10.8726,"value":163089.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 1, 2025."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $10.60 to $11.33, inclusive. The reporting person undertakes to provide to Fulcrum Therapeutics, Inc., any security holder of Fulcrum Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (2) to this Form 4. This Form 4/A corrects the weighted average price indicated in the Form 4 submitted on January 6, 2026 from $11.8726 to $10.8726."}],"balance_after":469864,"source":{"system":"sec-edgar","filing":"0001193125-26-037606","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000119312526037606/ownership.xml","form_type":"4/A","original_submission_date":"2026-01-06"}},{"id":919016,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67711,"kind":"person","name":"Oltmans Curtis Gale","position":1,"cik":"0001714982","reported_name":"Oltmans Curtis Gale","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Legal Officer"}}],"security":"Stock Option (right to buy)","published_at":"2026-02-04T21:10:05.000Z","date":"2026-02-02","kind":"grant","planned":false,"acquired":true,"shares":170000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 2, 2026 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2026, subject to the reporting person's continued service on each such vesting date."}],"balance_after":170000,"derivative":{"exercise_price":10.72,"expiration_date":"2036-02-01","underlying":"Common Stock","underlying_shares":170000},"source":{"system":"sec-edgar","filing":"0001193125-26-037576","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000119312526037576/ownership.xml","form_type":"4"}},{"id":919369,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-02-04T21:10:04.000Z","date":"2026-02-02","kind":"sale","planned":false,"acquired":false,"shares":15000,"price":10.7238,"value":160857.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 1, 2025."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $10.48 to $11.10, inclusive. The reporting person undertakes to provide to Fulcrum Therapeutics, Inc., any security holder of Fulcrum Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (2) to this Form 4."}],"balance_after":454864,"source":{"system":"sec-edgar","filing":"0001193125-26-037573","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000119312526037573/ownership.xml","form_type":"4"}},{"id":919015,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Principal Accounting Officer"}}],"security":"Stock Option (right to buy)","published_at":"2026-02-04T21:10:03.000Z","date":"2026-02-02","kind":"grant","planned":false,"acquired":true,"shares":57000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 2, 2026 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2026, subject to the reporting person's continued service on each such vesting date."}],"balance_after":57000,"derivative":{"exercise_price":10.72,"expiration_date":"2036-02-01","underlying":"Common Stock","underlying_shares":57000},"source":{"system":"sec-edgar","filing":"0001193125-26-037575","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000119312526037575/ownership.xml","form_type":"4"}},{"id":919014,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67709,"kind":"person","name":"Sapir Alex","position":1,"cik":"0001709415","reported_name":"Sapir Alex","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"See Remarks"}}],"security":"Stock option - Right to Buy","published_at":"2026-02-04T21:10:02.000Z","date":"2026-02-02","kind":"grant","planned":false,"acquired":true,"shares":650000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 2, 2026 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2026, subject to the reporting person's continued service on each such vesting date."}],"balance_after":650000,"derivative":{"exercise_price":10.72,"expiration_date":"2036-02-01","underlying":"Common Stock","underlying_shares":650000},"source":{"system":"sec-edgar","filing":"0001193125-26-037572","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000119312526037572/ownership.xml","form_type":"4"}},{"id":919251,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":30974,"kind":"person","name":"Musso Alan A","position":1,"cik":"0001295830","reported_name":"Musso Alan A","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Stock Option (right to buy)","published_at":"2026-02-04T16:10:05.000Z","date":"2026-02-02","kind":"grant","planned":false,"acquired":true,"shares":170000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 2, 2026 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2026, subject to the reporting person's continued service on each such vesting date."}],"balance_after":170000,"derivative":{"exercise_price":10.72,"expiration_date":"2036-02-01","underlying":"Common Stock","underlying_shares":170000},"source":{"system":"sec-edgar","filing":"0001193125-26-037574","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1295830/000119312526037574/ownership.xml","form_type":"4"}},{"id":946658,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-01-06T21:30:20.000Z","date":"2026-01-02","kind":"sale","planned":false,"acquired":false,"shares":15000,"price":11.8726,"value":178089.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 1, 2025."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $10.60 to $11.33, inclusive. The reporting person undertakes to provide to Fulcrum Therapeutics, Inc., any security holder of Fulcrum Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (2) to this Form 4."}],"balance_after":469864,"source":{"system":"sec-edgar","filing":"0001193125-26-004572","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000119312526004572/ownership.xml","form_type":"4"}},{"id":964221,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67711,"kind":"person","name":"Oltmans Curtis Gale","position":1,"cik":"0001714982","reported_name":"Oltmans Curtis Gale","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Legal Officer"}}],"security":"Common Stock","published_at":"2025-12-17T21:10:03.000Z","date":"2025-12-15","kind":"sale","planned":false,"acquired":false,"shares":3452,"price":12.92,"value":44599.84,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 8, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 10,252 shares that were previously acquired under the Issuer's employee stock purchase plan."}],"balance_after":10252,"source":{"system":"sec-edgar","filing":"0001193125-25-322740","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000119312525322740/ownership.xml","form_type":"4"}},{"id":974233,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-12-10T21:42:29.000Z","date":"2025-12-08","kind":"sale","planned":false,"acquired":false,"shares":91722,"price":14.98,"value":1373995.56,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F5","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.81 to $15.39 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Held directly by the Fund."}],"balance_after":6053960,"source":{"system":"sec-edgar","filing":"0001231919-25-000596","document":"form4-12102025_091221.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000123191925000596/form4-12102025_091221.xml","form_type":"4"}},{"id":974232,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-12-10T21:42:29.000Z","date":"2025-12-08","kind":"sale","planned":false,"acquired":false,"shares":2706397,"price":14.28,"value":38647349.16,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.81 to $14.805 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Held directly by the Fund."}],"balance_after":6145682,"source":{"system":"sec-edgar","filing":"0001231919-25-000596","document":"form4-12102025_091221.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000123191925000596/form4-12102025_091221.xml","form_type":"4"}},{"id":974231,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-12-10T21:42:29.000Z","date":"2025-12-08","kind":"sale","planned":false,"acquired":false,"shares":1377020,"price":13.33,"value":18355676.6,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $12.81 to $13.8099 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Held directly by the Fund."}],"balance_after":8852079,"source":{"system":"sec-edgar","filing":"0001231919-25-000596","document":"form4-12102025_091221.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000123191925000596/form4-12102025_091221.xml","form_type":"4"}},{"id":991267,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2025-11-21T21:15:03.000Z","date":"2025-11-19","kind":"sale","planned":false,"acquired":false,"shares":15000,"price":11.033,"value":165495.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 1, 2025."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $10.50 to $11.18, inclusive. The reporting person undertakes to provide to Fulcrum Therapeutics, Inc., any security holder of Fulcrum Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (2) to this Form 4."}],"balance_after":484864,"source":{"system":"sec-edgar","filing":"0001193125-25-291392","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000119312525291392/ownership.xml","form_type":"4"}},{"id":1099131,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32747,"kind":"person","name":"GERAGHTY JAMES A","position":1,"cik":"0001239746","reported_name":"GERAGHTY JAMES A","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:18.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091584","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1239746/000095017025091584/ownership.xml","form_type":"4"}},{"id":1098965,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":29690,"kind":"person","name":"Dorton Katina","position":1,"cik":"0001617541","reported_name":"Dorton Katina","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:16.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091583","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1617541/000095017025091583/ownership.xml","form_type":"4"}},{"id":1098944,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32613,"kind":"person","name":"Haviland Kate","position":1,"cik":"0001663022","reported_name":"Haviland Kate","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:14.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091582","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1663022/000095017025091582/ownership.xml","form_type":"4"}},{"id":1099271,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32860,"kind":"person","name":"Hill Colin","position":1,"cik":"0001673192","reported_name":"Hill Colin","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:09.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091580","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1673192/000095017025091580/ownership.xml","form_type":"4"}},{"id":1098974,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32645,"kind":"person","name":"King Rachel K.","position":1,"cik":"0001589712","reported_name":"King Rachel K.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:09.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091585","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1589712/000095017025091585/ownership.xml","form_type":"4"}},{"id":1099636,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":33367,"kind":"person","name":"Banks Sonja","position":1,"cik":"0001896415","reported_name":"Banks Sonja","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:07.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091579","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1896415/000095017025091579/ownership.xml","form_type":"4"}},{"id":1099229,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:05.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091578","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000095017025091578/ownership.xml","form_type":"4"}},{"id":1099337,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32908,"kind":"person","name":"Ezekowitz Alan","position":1,"cik":"0001780209","reported_name":"Ezekowitz Alan","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-30T20:15:04.000Z","date":"2025-06-26","kind":"grant","planned":false,"acquired":true,"shares":36000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 26, 2025 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":36000,"derivative":{"exercise_price":7.38,"expiration_date":"2035-06-25","underlying":"Common Stock","underlying_shares":36000},"source":{"system":"sec-edgar","filing":"0000950170-25-091577","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1780209/000095017025091577/ownership.xml","form_type":"4"}},{"id":1153262,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Principal Accounting Officer"}}],"security":"Common Stock","published_at":"2025-05-09T20:15:04.000Z","date":"2025-05-08","kind":"sale","planned":false,"acquired":false,"shares":498,"price":5.06,"value":2519.88,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sale reported on this Form 4 represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units. The sale occurred automatically to satisfy the tax withholding obligations to be funded by a \"sell to cover\" transaction and does not represent a discretionary trade by the Reporting Person."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 2,989 shares acquired under the Issuer's employee stock purchase plan on May 14, 2024."}],"balance_after":14062,"source":{"system":"sec-edgar","filing":"0000950170-25-068038","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017025068038/ownership.xml","form_type":"4"}},{"id":1292785,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67709,"kind":"person","name":"Sapir Alex","position":1,"cik":"0001709415","reported_name":"Sapir Alex","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"See Remarks"}}],"security":"Stock option - Right to Buy","published_at":"2025-01-28T21:15:11.000Z","date":"2025-01-24","kind":"grant","planned":false,"acquired":true,"shares":582000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on January 24, 2025 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2025, subject to the reporting person's continued service on each such vesting date."}],"balance_after":582000,"derivative":{"exercise_price":4.16,"expiration_date":"2035-01-23","underlying":"Common Stock","underlying_shares":582000},"source":{"system":"sec-edgar","filing":"0000950170-25-009816","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017025009816/ownership.xml","form_type":"4"}},{"id":1292784,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Principal Accounting Officer"}}],"security":"Stock Option (right to buy)","published_at":"2025-01-28T21:15:08.000Z","date":"2025-01-24","kind":"grant","planned":false,"acquired":true,"shares":76120,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on January 24, 2025 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2025, subject to the reporting person's continued service on each such vesting date."}],"balance_after":76120,"derivative":{"exercise_price":4.16,"expiration_date":"2035-01-23","underlying":"Common Stock","underlying_shares":76120},"source":{"system":"sec-edgar","filing":"0000950170-25-009815","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017025009815/ownership.xml","form_type":"4"}},{"id":1292780,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67711,"kind":"person","name":"Oltmans Curtis Gale","position":1,"cik":"0001714982","reported_name":"Oltmans Curtis Gale","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Legal Officer"}}],"security":"Stock Option (right to buy)","published_at":"2025-01-28T21:15:06.000Z","date":"2025-01-24","kind":"grant","planned":false,"acquired":true,"shares":225000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on January 24, 2025 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2025, subject to the reporting person's continued service on each such vesting date."}],"balance_after":225000,"derivative":{"exercise_price":4.16,"expiration_date":"2035-01-24","underlying":"Common Stock","underlying_shares":225000},"source":{"system":"sec-edgar","filing":"0000950170-25-009813","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017025009813/ownership.xml","form_type":"4"}},{"id":1292930,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":30974,"kind":"person","name":"Musso Alan A","position":1,"cik":"0001295830","reported_name":"Musso Alan A","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Stock Option (right to buy)","published_at":"2025-01-28T16:15:14.000Z","date":"2025-01-24","kind":"grant","planned":false,"acquired":true,"shares":285000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on January 24, 2025 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2025, subject to the reporting person's continued service on each such vesting date."}],"balance_after":285000,"derivative":{"exercise_price":4.16,"expiration_date":"2035-01-23","underlying":"Common Stock","underlying_shares":285000},"source":{"system":"sec-edgar","filing":"0000950170-25-009818","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1295830/000095017025009818/ownership.xml","form_type":"4"}},{"id":1364781,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32645,"kind":"person","name":"King Rachel K.","position":1,"cik":"0001589712","reported_name":"King Rachel K.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-11-14T21:15:03.000Z","date":"2024-11-12","kind":"grant","planned":false,"acquired":true,"shares":60000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on November 12, 2024 and is scheduled to vest in equal monthly installments until November 12, 2027, subject to continued service."}],"balance_after":60000,"derivative":{"exercise_price":3.64,"expiration_date":"2034-11-11","underlying":"Common Stock","underlying_shares":60000},"source":{"system":"sec-edgar","filing":"0000950170-24-127074","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1589712/000095017024127074/ownership.xml","form_type":"4"}},{"id":1424087,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Warrant (Right to Buy)","published_at":"2024-08-23T20:10:05.000Z","date":"2024-08-21","kind":"other","planned":false,"acquired":true,"shares":8500000,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"RA Capital Healthcare Fund, L.P. (the \"Fund\") entered into an Exchange Agreement with the Issuer pursuant to which the Fund exchanged, on a 1:1 basis, 8,500,000 shares of the Issuer's Common Stock for an equal number of prefunded warrants, each to purchase one share of the Issuer's Common Stock at an exercise price of $0.001 per share (each a \"Pre-Funded Warrant\")."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"RA Capital Healthcare Fund, L.P. (the \"Fund\") entered into an Exchange Agreement with the Issuer pursuant to which the Fund exchanged, on a 1:1 basis, 8,500,000 shares of the Issuer's Common Stock for an equal number of prefunded warrants, each to purchase one share of the Issuer's Common Stock at an exercise price of $0.001 per share (each a \"Pre-Funded Warrant\")."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"The Pre-Funded Warrants have no expiration date and are exercisable immediately. Notwithstanding the foregoing, the Reporting Persons shall not be entitled to exercise the Pre-Funded Warrant if it would cause the aggregate number of shares of Common Stock beneficially owned by the Reporting Persons, their affiliates and any persons who are members of a Section 13(d) group with the Reporting Persons or their affiliates to exceed 9.99% of the total number of issued and outstanding shares of Common Stock of the Issuer following such exercise."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"The Pre-Funded Warrants have no expiration date and are exercisable immediately. Notwithstanding the foregoing, the Reporting Persons shall not be entitled to exercise the Pre-Funded Warrant if it would cause the aggregate number of shares of Common Stock beneficially owned by the Reporting Persons, their affiliates and any persons who are members of a Section 13(d) group with the Reporting Persons or their affiliates to exceed 9.99% of the total number of issued and outstanding shares of Common Stock of the Issuer following such exercise."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Held directly by the Fund."}],"balance_after":8500000,"derivative":{"exercise_price":0.001,"underlying":"Common Stock","underlying_shares":8500000},"source":{"system":"sec-edgar","filing":"0001415889-24-022127","document":"form4-08232024_040801.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000141588924022127/form4-08232024_040801.xml","form_type":"4"}},{"id":1424086,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2024-08-23T20:10:05.000Z","date":"2024-08-21","kind":"other","planned":false,"acquired":false,"shares":8500000,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"RA Capital Healthcare Fund, L.P. (the \"Fund\") entered into an Exchange Agreement with the Issuer pursuant to which the Fund exchanged, on a 1:1 basis, 8,500,000 shares of the Issuer's Common Stock for an equal number of prefunded warrants, each to purchase one share of the Issuer's Common Stock at an exercise price of $0.001 per share (each a \"Pre-Funded Warrant\")."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"RA Capital Healthcare Fund, L.P. (the \"Fund\") entered into an Exchange Agreement with the Issuer pursuant to which the Fund exchanged, on a 1:1 basis, 8,500,000 shares of the Issuer's Common Stock for an equal number of prefunded warrants, each to purchase one share of the Issuer's Common Stock at an exercise price of $0.001 per share (each a \"Pre-Funded Warrant\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Held directly by the Fund."}],"balance_after":3109704,"source":{"system":"sec-edgar","filing":"0001415889-24-022127","document":"form4-08232024_040801.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000141588924022127/form4-08232024_040801.xml","form_type":"4"}},{"id":1458122,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67709,"kind":"person","name":"Sapir Alex","position":1,"cik":"0001709415","reported_name":"Sapir Alex","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"See Remarks"}}],"security":"Stock option - Right to Buy","published_at":"2024-07-08T12:00:03.000Z","date":"2024-07-03","kind":"exercise","planned":false,"acquired":false,"shares":150000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"This transaction involved a cash exercise of a stock option without a subsequent sale of the underlying shares of common stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"This option was granted on May 12, 2023 and vested 25% on the first anniversary of the vesting commencement date of May 12, 2023. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years until the fourth anniversary of the vesting commencement date, subject to continued service."}],"balance_after":2280400,"derivative":{"exercise_price":3.27,"expiration_date":"2033-05-11","underlying":"Common Stock","underlying_shares":150000},"source":{"system":"sec-edgar","filing":"0000950170-24-081949","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024081949/ownership.xml","form_type":"4"}},{"id":1458121,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67709,"kind":"person","name":"Sapir Alex","position":1,"cik":"0001709415","reported_name":"Sapir Alex","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"See Remarks"}}],"security":"Common Stock","published_at":"2024-07-08T12:00:03.000Z","date":"2024-07-03","kind":"exercise","planned":false,"acquired":true,"shares":150000,"price":3.27,"value":490500.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"This transaction involved a cash exercise of a stock option without a subsequent sale of the underlying shares of common stock."}],"balance_after":193360,"source":{"system":"sec-edgar","filing":"0000950170-24-081949","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024081949/ownership.xml","form_type":"4"}},{"id":1475445,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32908,"kind":"person","name":"Ezekowitz Alan","position":1,"cik":"0001780209","reported_name":"Ezekowitz Alan","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T20:20:20.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-24-074892","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1780209/000095017024074892/ownership.xml","form_type":"4"}},{"id":1475239,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T20:20:14.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-24-074888","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000095017024074888/ownership.xml","form_type":"4"}},{"id":1474476,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32613,"kind":"person","name":"Haviland Kate","position":1,"cik":"0001663022","reported_name":"Haviland Kate","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T20:20:13.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-24-074887","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1663022/000095017024074887/ownership.xml","form_type":"4"}},{"id":1474982,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32747,"kind":"person","name":"GERAGHTY JAMES A","position":1,"cik":"0001239746","reported_name":"GERAGHTY JAMES A","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T20:20:09.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-24-074885","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1239746/000095017024074885/ownership.xml","form_type":"4"}},{"id":1474583,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":29690,"kind":"person","name":"Dorton Katina","position":1,"cik":"0001617541","reported_name":"Dorton Katina","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T20:20:07.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-24-074884","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1617541/000095017024074884/ownership.xml","form_type":"4"}},{"id":1476271,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":33367,"kind":"person","name":"Banks Sonja","position":1,"cik":"0001896415","reported_name":"Banks Sonja","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T20:20:03.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-24-074882","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1896415/000095017024074882/ownership.xml","form_type":"4"}},{"id":1475357,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32860,"kind":"person","name":"Hill Colin","position":1,"cik":"0001673192","reported_name":"Hill Colin","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T20:15:04.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":60000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest in equal monthly installments until June 17, 2027, subject to continued service."}],"balance_after":60000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":60000},"source":{"system":"sec-edgar","filing":"0000950170-24-074868","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1673192/000095017024074868/ownership.xml","form_type":"4"}},{"id":1475446,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":78050,"kind":"person","name":"Collins James J.","position":1,"cik":"0001779269","reported_name":"Collins James J.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-18T16:20:06.000Z","date":"2024-06-17","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 17, 2024 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":7,"expiration_date":"2034-06-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-24-074883","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1779269/000095017024074883/ownership.xml","form_type":"4"}},{"id":1521799,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Principal Accounting Officer"}}],"security":"Common Stock","published_at":"2024-05-09T20:10:08.000Z","date":"2024-05-07","kind":"sale","planned":false,"acquired":false,"shares":236,"price":7.76,"value":1831.36,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sale reported on this Form 4 represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units. The sale occurred automatically to satisfy the tax withholding obligations to be funded by a \"sell to cover\" transaction and does not represent a discretionary trade by the Reporting Person."}],"balance_after":11571,"source":{"system":"sec-edgar","filing":"0000950170-24-056947","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024056947/ownership.xml","form_type":"4"}},{"id":1565719,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":92811,"kind":"person","name":"Horn Patrick Taylor","position":1,"cik":"0001572002","reported_name":"Horn Patrick Taylor","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Medical Officer"}}],"security":"Stock Option (right to buy)","published_at":"2024-03-20T16:15:10.000Z","date":"2024-03-18","kind":"grant","planned":false,"acquired":true,"shares":400000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on March 18, 2024 and is scheduled to vest 25% on the first anniversary of the vesting commencement date of March 18, 2024. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years until the fourth anniversary of the vesting commencement date, subject to continued service."}],"balance_after":400000,"derivative":{"exercise_price":10.12,"expiration_date":"2034-03-17","underlying":"Common Stock","underlying_shares":400000},"source":{"system":"sec-edgar","filing":"0000950170-24-034177","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1572002/000095017024034177/ownership.xml","form_type":"4"}},{"id":1585904,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Vice President, Finance"}}],"security":"Common Stock","published_at":"2024-03-08T23:05:06.000Z","date":"2024-03-08","kind":"sale","planned":false,"acquired":false,"shares":4884,"price":11.7155,"value":57218.502,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $11.71 to $11.74, inclusive. The reporting person undertakes to provide to Fulcrum Therapeutics, Inc., any security holder of Fulcrum Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (1) to this Form 4."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 699 shares acquired under the Issuer's employee stock purchase plan on May 13, 2022."}],"balance_after":11807,"source":{"system":"sec-edgar","filing":"0000950170-24-028827","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024028827/ownership.xml","form_type":"4"}},{"id":1593864,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67709,"kind":"person","name":"Sapir Alex","position":1,"cik":"0001709415","reported_name":"Sapir Alex","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"See Remarks"}}],"security":"Common Stock","published_at":"2024-03-05T21:15:17.000Z","date":"2024-03-04","kind":"purchase","planned":false,"acquired":true,"shares":43360,"price":11.3475,"value":492027.6,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $10.96 to $11.50, inclusive. The reporting person undertakes to provide to Fulcrum Therapeutics, Inc., any security holder of Fulcrum Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote (1) to this Form 4."}],"balance_after":43360,"source":{"system":"sec-edgar","filing":"0000950170-24-025933","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024025933/ownership.xml","form_type":"4"}},{"id":1666245,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Vice President, Finance"}}],"security":"Stock Option (right to buy)","published_at":"2024-01-31T02:10:04.000Z","date":"2024-01-26","kind":"grant","planned":false,"acquired":true,"shares":10000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"This option was granted on January 26, 2024 and is scheduled to vest in equal yearly installments over two years beginning on the vesting commencement date of January 1, 2024, subject to the reporting person's continued service on each such vesting date."}],"balance_after":10000,"derivative":{"exercise_price":6.95,"expiration_date":"2034-01-25","underlying":"Common Stock","underlying_shares":10000},"source":{"system":"sec-edgar","filing":"0000950170-24-009096","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024009096/ownership.xml","form_type":"4"}},{"id":1666244,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Vice President, Finance"}}],"security":"Stock Option (right to buy)","published_at":"2024-01-31T02:10:04.000Z","date":"2024-01-26","kind":"grant","planned":false,"acquired":true,"shares":83820,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on January 26, 2024 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2024, subject to the reporting person's continued service on each such vesting date."}],"balance_after":83820,"derivative":{"exercise_price":6.95,"expiration_date":"2034-01-25","underlying":"Common Stock","underlying_shares":83820},"source":{"system":"sec-edgar","filing":"0000950170-24-009096","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024009096/ownership.xml","form_type":"4"}},{"id":1666243,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67711,"kind":"person","name":"Oltmans Curtis Gale","position":1,"cik":"0001714982","reported_name":"Oltmans Curtis Gale","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Legal Officer"}}],"security":"Stock Option (right to buy)","published_at":"2024-01-31T02:00:05.000Z","date":"2024-01-26","kind":"grant","planned":false,"acquired":true,"shares":150000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on January 26, 2024 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2024, subject to the reporting person's continued service on each such vesting date."}],"balance_after":150000,"derivative":{"exercise_price":6.95,"expiration_date":"2034-01-25","underlying":"Common Stock","underlying_shares":150000},"source":{"system":"sec-edgar","filing":"0000950170-24-009092","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017024009092/ownership.xml","form_type":"4"}},{"id":1666415,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":30974,"kind":"person","name":"Musso Alan A","position":1,"cik":"0001295830","reported_name":"Musso Alan A","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Stock Option (right to buy)","published_at":"2024-01-30T21:05:10.000Z","date":"2024-01-26","kind":"grant","planned":false,"acquired":true,"shares":100000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on January 26, 2024 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2024, subject to the reporting person's continued service on each such vesting date."}],"balance_after":100000,"derivative":{"exercise_price":6.95,"expiration_date":"2034-01-25","underlying":"Common Stock","underlying_shares":100000},"source":{"system":"sec-edgar","filing":"0000950170-24-009094","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1295830/000095017024009094/ownership.xml","form_type":"4"}},{"id":1675096,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":30974,"kind":"person","name":"Musso Alan A","position":1,"cik":"0001295830","reported_name":"Musso Alan A","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Stock Option (right to buy)","published_at":"2024-01-19T16:15:05.000Z","date":"2024-01-17","kind":"grant","planned":false,"acquired":true,"shares":61822,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"This performance-based stock option was granted on August 7, 2023 and is subject to the achievement of certain pre-defined performance objectives pertaining to financial and investor relations goals within six months from the grant date, and subject to Mr. Musso continuing to be an \"eligible participant\" (as defined in Fulcrum Therapeutics, Inc.'s 2022 Inducement Stock Incentive  Plan) through the vesting date. All performance objectives were met on January 17, 2024."}],"balance_after":61822,"derivative":{"exercise_price":4.01,"exercise_date":"2024-02-07","expiration_date":"2033-08-06","underlying":"Common Stock","underlying_shares":61822},"source":{"system":"sec-edgar","filing":"0000950170-24-005790","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1295830/000095017024005790/ownership.xml","form_type":"4"}},{"id":1811873,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":30974,"kind":"person","name":"Musso Alan A","position":1,"cik":"0001295830","reported_name":"Musso Alan A","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Stock Option (right to buy)","published_at":"2023-08-09T16:16:29.000Z","date":"2023-08-07","kind":"grant","planned":false,"acquired":true,"shares":432800,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on August 7, 2023 and is scheduled to vest 25% on the first anniversary of the vesting commencement date of August 7, 2023. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years until the fourth anniversary of the vesting commencement date, subject to continued service."}],"balance_after":432800,"derivative":{"exercise_price":4.01,"expiration_date":"2033-08-06","underlying":"Common Stock","underlying_shares":432800},"source":{"system":"sec-edgar","filing":"0000950170-23-040615","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1295830/000095017023040615/ownership.xml","form_type":"4"}},{"id":1841914,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32747,"kind":"person","name":"GERAGHTY JAMES A","position":1,"cik":"0001239746","reported_name":"GERAGHTY JAMES A","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2023-06-29T20:23:17.000Z","date":"2023-06-27","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2023 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":3.16,"expiration_date":"2033-06-26","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-23-030765","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1239746/000095017023030765/ownership.xml","form_type":"4"}},{"id":1841791,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32613,"kind":"person","name":"Haviland Kate","position":1,"cik":"0001663022","reported_name":"Haviland Kate","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2023-06-29T20:16:52.000Z","date":"2023-06-27","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2023 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":3.16,"expiration_date":"2033-06-26","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-23-030757","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1663022/000095017023030757/ownership.xml","form_type":"4"}},{"id":1842307,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":33367,"kind":"person","name":"Banks Sonja","position":1,"cik":"0001896415","reported_name":"Banks Sonja","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2023-06-29T20:16:51.000Z","date":"2023-06-27","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2023 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":3.16,"expiration_date":"2033-06-26","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-23-030758","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1896415/000095017023030758/ownership.xml","form_type":"4"}},{"id":1841796,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":29690,"kind":"person","name":"Dorton Katina","position":1,"cik":"0001617541","reported_name":"Dorton Katina","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (Right to Buy)","published_at":"2023-06-29T20:16:51.000Z","date":"2023-06-27","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2023 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":3.16,"expiration_date":"2033-06-26","underlying":"Common Stock","underlying_shares":0},"source":{"system":"sec-edgar","filing":"0000950170-23-030756","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1617541/000095017023030756/ownership.xml","form_type":"4"}},{"id":1842051,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32908,"kind":"person","name":"Ezekowitz Alan","position":1,"cik":"0001780209","reported_name":"Ezekowitz Alan","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2023-06-29T20:16:17.000Z","date":"2023-06-27","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2023 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":3.16,"expiration_date":"2033-06-26","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-23-030755","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1780209/000095017023030755/ownership.xml","form_type":"4"}},{"id":1841984,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Interim President & CEO"}}],"security":"Stock Option (right to buy)","published_at":"2023-06-29T20:16:13.000Z","date":"2023-06-27","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2023 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":3.16,"expiration_date":"2033-06-26","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-23-030753","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000095017023030753/ownership.xml","form_type":"4"}},{"id":1842053,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":78050,"kind":"person","name":"Collins James J.","position":1,"cik":"0001779269","reported_name":"Collins James J.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2023-06-29T16:16:09.000Z","date":"2023-06-27","kind":"grant","planned":false,"acquired":true,"shares":30000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2023 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":30000,"derivative":{"exercise_price":3.16,"expiration_date":"2033-06-26","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0000950170-23-030752","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1779269/000095017023030752/ownership.xml","form_type":"4"}},{"id":1896339,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Principal Accounting Officer"}}],"security":"Common Stock","published_at":"2023-05-11T20:12:00.000Z","date":"2023-05-10","kind":"sale","planned":false,"acquired":false,"shares":210,"price":3.31,"value":695.1,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sale reported on this Form 4 represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units. The sale occurred automatically to satisfy the tax withholding obligations to be funded by a \"sell to cover\" transaction and does not represent a discretionary trade by the Reporting Person."}],"balance_after":15992,"source":{"system":"sec-edgar","filing":"0000950170-23-021245","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017023021245/ownership.xml","form_type":"4"}},{"id":1911135,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":114081,"kind":"person","name":"Hayes Melvin H. III","position":1,"cik":"0001937148","reported_name":"Hayes Melvin H. III","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Stock Option (right to buy)","published_at":"2023-04-28T20:17:16.000Z","date":"2023-04-26","kind":"grant","planned":false,"acquired":true,"shares":115000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"These stock options were granted to the reporting person under the Fulcrum 2019 Stock Incentive Plan (the \"Plan\") as part of an executive retention program and will vest 25% on the first anniversary of the grant date. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years, such that the options will be vested in full on the four-year anniversary of the grant date, and subject to the reporting person's continuing to be an \"Eligible Participant\" (as defined in the Plan) on each such vesting date."}],"balance_after":115000,"derivative":{"exercise_price":2.58,"expiration_date":"2033-04-25","underlying":"Common Stock","underlying_shares":115000},"source":{"system":"sec-edgar","filing":"0000950170-23-015832","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017023015832/ownership.xml","form_type":"4"}},{"id":1911136,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67711,"kind":"person","name":"Oltmans Curtis Gale","position":1,"cik":"0001714982","reported_name":"Oltmans Curtis Gale","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Legal Officer"}}],"security":"Stock Option (right to buy)","published_at":"2023-04-28T20:16:04.000Z","date":"2023-04-26","kind":"grant","planned":false,"acquired":true,"shares":127500,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"These stock options were granted to the reporting person under the Fulcrum 2019 Stock Incentive Plan (the \"Plan\") as part of an executive retention program and will vest 25% on the first anniversary of the grant date. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years, such that the options will be vested in full on the four-year anniversary of the grant date, and subject to the reporting person's continuing to be an \"Eligible Participant\" (as defined in the Plan) on each such vesting date."}],"balance_after":127500,"derivative":{"exercise_price":2.58,"expiration_date":"2033-04-25","underlying":"Common Stock","underlying_shares":127500},"source":{"system":"sec-edgar","filing":"0000950170-23-015824","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000095017023015824/ownership.xml","form_type":"4"}},{"id":2019359,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67711,"kind":"person","name":"Oltmans Curtis Gale","position":1,"cik":"0001714982","reported_name":"Oltmans Curtis Gale","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Legal Officer"}}],"security":"Stock Option (right to buy)","published_at":"2023-02-13T21:15:31.000Z","date":"2023-02-09","kind":"grant","acquired":true,"shares":150000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 9, 2023 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2023, subject to the reporting person's continued service on each such vesting date."}],"balance_after":150000,"derivative":{"exercise_price":12.59,"expiration_date":"2033-02-08","underlying":"Common Stock","underlying_shares":150000},"source":{"system":"sec-edgar","filing":"0000899243-23-004745","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924323004745/doc4.xml","form_type":"4"}},{"id":2019356,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Controller"}}],"security":"Stock Option (right to buy)","published_at":"2023-02-13T21:15:26.000Z","date":"2023-02-09","kind":"grant","acquired":true,"shares":16100,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 9, 2023 and is is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2023, subject to the reporting person's continued service on each such vesting date."}],"balance_after":16100,"derivative":{"exercise_price":12.59,"expiration_date":"2033-02-08","underlying":"Common Stock","underlying_shares":16100},"source":{"system":"sec-edgar","filing":"0000899243-23-004744","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924323004744/doc4.xml","form_type":"4"}},{"id":2019358,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":114081,"kind":"person","name":"Hayes Melvin H. III","position":1,"cik":"0001937148","reported_name":"Hayes Melvin H. III","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Stock Option (right to buy)","published_at":"2023-02-13T21:15:15.000Z","date":"2023-02-09","kind":"grant","acquired":true,"shares":135000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 9, 2023 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2023, subject to the reporting person's continued service on each such vesting date."}],"balance_after":135000,"derivative":{"exercise_price":12.59,"expiration_date":"2033-02-08","underlying":"Common Stock","underlying_shares":135000},"source":{"system":"sec-edgar","filing":"0000899243-23-004743","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924323004743/doc4.xml","form_type":"4"}},{"id":2019357,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":49376,"kind":"person","name":"Rajavelu Esther","position":1,"cik":"0001903716","reported_name":"Rajavelu Esther","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Stock Option (right to buy)","published_at":"2023-02-13T21:15:14.000Z","date":"2023-02-09","kind":"grant","acquired":true,"shares":160000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on February 9, 2023 and is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of January 1, 2023, subject to the reporting person's continued service on each such vesting date."}],"balance_after":160000,"derivative":{"exercise_price":12.59,"expiration_date":"2033-02-08","underlying":"Common Stock","underlying_shares":160000},"source":{"system":"sec-edgar","filing":"0000899243-23-004742","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924323004742/doc4.xml","form_type":"4"}},{"id":2047329,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2023-01-24T21:30:47.000Z","date":"2023-01-20","kind":"purchase","acquired":true,"shares":1923076,"price":13,"value":24999988.0,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":11609704,"source":{"system":"sec-edgar","filing":"0001104659-23-006213","document":"tm234291-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465923006213/tm234291-1_4seq1.xml","form_type":"4"}},{"id":2054714,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Interim President & CEO"}}],"security":"Common Stock","published_at":"2023-01-13T23:33:36.000Z","date":"2023-01-13","kind":"sale","acquired":false,"shares":6766,"price":15,"value":101490.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on September 7, 2022."}],"balance_after":499864,"source":{"system":"sec-edgar","filing":"0000899243-23-001803","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000089924323001803/doc4.xml","form_type":"4"}},{"id":2060074,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2023-01-06T21:39:05.000Z","date":"2023-01-04","kind":"purchase","acquired":true,"shares":58369,"price":7.7968,"value":455091.4192,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"This transaction was executed in multiple trades at prices ranging from $7.64 to $8.00; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Held directly by the Fund."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F4","text":"Held directly by the Fund."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F5","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":9686628,"source":{"system":"sec-edgar","filing":"0001104659-23-001881","document":"tm232548-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465923001881/tm232548-1_4seq1.xml","form_type":"4"}},{"id":2060073,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2023-01-06T21:39:05.000Z","date":"2023-01-04","kind":"purchase","acquired":true,"shares":122334,"price":7.0276,"value":859714.4184,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"This transaction was executed in multiple trades at prices ranging from $6.64 to $7.63; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F5","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":9628259,"source":{"system":"sec-edgar","filing":"0001104659-23-001881","document":"tm232548-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465923001881/tm232548-1_4seq1.xml","form_type":"4"}},{"id":2074842,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2022-12-29T22:00:41.000Z","date":"2022-12-27","kind":"purchase","acquired":true,"shares":4089,"price":5.9941,"value":24509.8749,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"This transaction was executed in multiple trades at prices ranging from $5.98 to $6.00; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":9505925,"source":{"system":"sec-edgar","filing":"0001104659-22-130982","document":"tm2233686-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465922130982/tm2233686-1_4seq1.xml","form_type":"4"}},{"id":2078557,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2022-12-21T21:30:26.000Z","date":"2022-12-19","kind":"purchase","acquired":true,"shares":98787,"price":5.8997,"value":582813.6639,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"This transaction was executed in multiple trades at prices ranging from $5.79 to $6.00; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":9501836,"source":{"system":"sec-edgar","filing":"0001104659-22-129121","document":"tm2233247-1_4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465922129121/tm2233247-1_4.xml","form_type":"4"}},{"id":2083485,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2022-12-16T21:41:46.000Z","date":"2022-12-16","kind":"purchase","acquired":true,"shares":1341420,"price":5.4195,"value":7269825.69,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"This transaction was executed in multiple trades at prices ranging from $5.25 to $5.69; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F5","text":"Held directly by the Fund."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F5","text":"Held directly by the Fund."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F6","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":9403049,"source":{"system":"sec-edgar","filing":"0001104659-22-127883","document":"tm2232930-1_4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465922127883/tm2232930-1_4.xml","form_type":"4"}},{"id":2083484,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2022-12-16T21:41:46.000Z","date":"2022-12-15","kind":"purchase","acquired":true,"shares":237029,"price":5.495,"value":1302474.355,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"This transaction was executed in multiple trades at prices ranging from $5.35 to $5.50; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Held directly by the Fund."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Held directly by the Fund."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F6","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":8061629,"source":{"system":"sec-edgar","filing":"0001104659-22-127883","document":"tm2232930-1_4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465922127883/tm2232930-1_4.xml","form_type":"4"}},{"id":2083483,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":19524,"kind":"organization","name":"RA CAPITAL MANAGEMENT, L.P.","position":1,"cik":"0001346824","reported_name":"RA CAPITAL MANAGEMENT, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19525,"kind":"organization","name":"RA Capital Healthcare Fund LP","position":2,"cik":"0001315082","reported_name":"RA Capital Healthcare Fund LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19526,"kind":"person","name":"Kolchinsky Peter","position":3,"cik":"0001384859","reported_name":"Kolchinsky Peter","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":19527,"kind":"person","name":"Shah Rajeev M.","position":4,"cik":"0001619841","reported_name":"Shah Rajeev M.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2022-12-16T21:41:46.000Z","date":"2022-12-14","kind":"purchase","acquired":true,"shares":824600,"price":5.4591,"value":4501573.86,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Held directly by RA Capital Healthcare Fund, L.P. (the \"Fund\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F6","text":"RA Capital Management, L.P. (the \"Adviser\") is the investment manager for the Fund. The general partner of the Adviser is RA Capital Management GP, LLC (the \"Adviser GP\"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein."}],"balance_after":7824600,"source":{"system":"sec-edgar","filing":"0001104659-22-127883","document":"tm2232930-1_4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1315082/000110465922127883/tm2232930-1_4.xml","form_type":"4"}},{"id":2084907,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":117227,"kind":"organization","name":"Third Rock Ventures III, L.P.","position":1,"cik":"0001569705","reported_name":"Third Rock Ventures III, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":117228,"kind":"organization","name":"Third Rock Ventures GP III, L.P.","position":2,"cik":"0001637300","reported_name":"Third Rock Ventures GP III, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":104800,"kind":"organization","name":"TRV GP III, LLC","position":3,"cik":"0001637299","reported_name":"TRV GP III, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":104809,"kind":"person","name":"Tepper Robert I","position":4,"cik":"0001192595","reported_name":"TEPPER ROBERT I","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2022-12-15T16:30:20.000Z","date":"2022-12-13","kind":"other","acquired":false,"shares":2000000,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"On December 13, 2022, Third Rock Ventures III, L.P. (\"TRV III\") distributed for no consideration, 2,000,000 shares of Common Stock of the Issuer (the \"Shares\") to its limited partners and to Third Rock Ventures GP III, L.P. (\"TRV GP III\"), the general partner of TRV III, representing each such partner's pro rata interest in such Shares. On the same date, TRV GP III distributed, for no consideration, the Shares it received in the distribution by TRV III to its partners, representing each such partner's pro rata interest in such Shares. All of the aforementioned distributions were made in accordance with the exemptions afforded by Rules 16a-13 and 16a-9 of the Securities Exchange Act of 1934, as amended."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"On December 13, 2022, Third Rock Ventures III, L.P. (\"TRV III\") distributed for no consideration, 2,000,000 shares of Common Stock of the Issuer (the \"Shares\") to its limited partners and to Third Rock Ventures GP III, L.P. (\"TRV GP III\"), the general partner of TRV III, representing each such partner's pro rata interest in such Shares. On the same date, TRV GP III distributed, for no consideration, the Shares it received in the distribution by TRV III to its partners, representing each such partner's pro rata interest in such Shares. All of the aforementioned distributions were made in accordance with the exemptions afforded by Rules 16a-13 and 16a-9 of the Securities Exchange Act of 1934, as amended."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F2","text":"These shares are directly held by TRV III. The general partner of TRV III is TRV GP III. The general partner of TRV GP III is TRV GP III, LLC (\"TRV GP III LLC\"). The individual manager of TRV GP III LLC is Dr. Robert Tepper (\"Tepper\"). Each of TRV GP III, TRV GP III LLC and Tepper disclaims beneficial ownership of the shares except to the extent of its or his pecuniary interest therein, if any, and this report shall not be deemed an admission that it or he is the beneficial owner of such shares."}],"balance_after":1962202,"source":{"system":"sec-edgar","filing":"0000899243-22-038602","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1192595/000089924322038602/doc4.xml","form_type":"4"}},{"id":2120831,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":84384,"kind":"person","name":"Arroyo Santiago","position":1,"cik":"0001706857","reported_name":"Arroyo Santiago","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Medical Officer"}}],"security":"Stock Option (right to buy)","published_at":"2022-11-09T21:15:14.000Z","date":"2022-11-07","kind":"grant","acquired":true,"shares":400000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on November 7, 2022 and is scheduled to vest 25% on the first anniversary of the vesting commencement date of November 7, 2022. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years until the fourth anniversary of the vesting commencement date, subject to continued service."}],"balance_after":400000,"derivative":{"exercise_price":5.61,"expiration_date":"2032-11-06","underlying":"Common Stock","underlying_shares":400000},"source":{"system":"sec-edgar","filing":"0000899243-22-035434","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924322035434/doc4.xml","form_type":"4"}},{"id":2187771,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":114081,"kind":"person","name":"Hayes Melvin H. III","position":1,"cik":"0001937148","reported_name":"Hayes Melvin H. III","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Stock Option (right to buy)","published_at":"2022-08-11T20:15:39.000Z","date":"2022-08-09","kind":"grant","acquired":true,"shares":137000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on August 9, 2022 and is scheduled to vest 25% on the first anniversary of the vesting commencement date of August 9, 2022. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years until the fourth anniversary of the vesting commencement date, subject to continued service."}],"balance_after":137000,"derivative":{"exercise_price":7.4,"expiration_date":"2032-08-08","underlying":"Common Stock","underlying_shares":137000},"source":{"system":"sec-edgar","filing":"0000899243-22-028370","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924322028370/doc4.xml","form_type":"4"}},{"id":2187770,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67711,"kind":"person","name":"Oltmans Curtis Gale","position":1,"cik":"0001714982","reported_name":"Oltmans Curtis Gale","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Legal Officer"}}],"security":"Stock Option (right to buy)","published_at":"2022-08-11T20:15:30.000Z","date":"2022-08-09","kind":"grant","acquired":true,"shares":50000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on August 9, 2022 and is scheduled to vest 25% on the first anniversary of the vesting commencement date of August 9, 2022. The remainder of the shares underlying the grant shall vest in equal quarterly installments over the following three years until the fourth anniversary of the vesting commencement date, subject to continued service"}],"balance_after":50000,"derivative":{"exercise_price":7.4,"expiration_date":"2032-08-08","underlying":"Common Stock","underlying_shares":50000},"source":{"system":"sec-edgar","filing":"0000899243-22-028368","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924322028368/doc4.xml","form_type":"4"}},{"id":2205053,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":67710,"kind":"person","name":"Tourangeau Greg","position":1,"cik":"0001916566","reported_name":"Tourangeau Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Controller"}}],"security":"Stock Option (right to buy)","published_at":"2022-07-19T20:15:26.000Z","date":"2022-07-15","kind":"grant","acquired":true,"shares":16540,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on July 15, 2022 and is is scheduled to vest in equal quarterly installments over four years beginning on the vesting commencement date of July 1, 2022, subject to the reporting person's continued service on each such vesting date."}],"balance_after":16540,"derivative":{"exercise_price":5.39,"expiration_date":"2032-07-14","underlying":"Common Stock","underlying_shares":16540},"source":{"system":"sec-edgar","filing":"0000899243-22-026322","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1680581/000089924322026322/doc4.xml","form_type":"4"}},{"id":2219405,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32908,"kind":"person","name":"Ezekowitz Alan","position":1,"cik":"0001780209","reported_name":"Ezekowitz Alan","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T21:00:51.000Z","date":"2022-06-28","kind":"other","acquired":false,"shares":500,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"No value was received for the cancellation of these stock options, which were originally granted on December 3, 2020."}],"balance_after":14500,"derivative":{"exercise_price":11.82,"expiration_date":"2030-12-02","underlying":"Common Stock","underlying_shares":500},"source":{"system":"sec-edgar","filing":"0000899243-22-024528","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1780209/000089924322024528/doc4.xml","form_type":"4"}},{"id":2219404,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32908,"kind":"person","name":"Ezekowitz Alan","position":1,"cik":"0001780209","reported_name":"Ezekowitz Alan","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T21:00:51.000Z","date":"2022-06-27","kind":"grant","acquired":true,"shares":19000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2022 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":19000,"derivative":{"exercise_price":5.22,"expiration_date":"2032-06-26","underlying":"Common Stock","underlying_shares":19000},"source":{"system":"sec-edgar","filing":"0000899243-22-024528","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1780209/000089924322024528/doc4.xml","form_type":"4"}},{"id":2219161,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32613,"kind":"person","name":"Haviland Kate","position":1,"cik":"0001663022","reported_name":"Haviland Kate","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T21:00:47.000Z","date":"2022-06-27","kind":"grant","acquired":true,"shares":19000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2022 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":19000,"derivative":{"exercise_price":5.22,"expiration_date":"2032-06-26","underlying":"Common Stock","underlying_shares":19000},"source":{"system":"sec-edgar","filing":"0000899243-22-024525","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1663022/000089924322024525/doc4.xml","form_type":"4"}},{"id":2219295,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32747,"kind":"person","name":"GERAGHTY JAMES A","position":1,"cik":"0001239746","reported_name":"GERAGHTY JAMES A","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T21:00:45.000Z","date":"2022-06-27","kind":"grant","acquired":true,"shares":19000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2022 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":19000,"derivative":{"exercise_price":5.22,"expiration_date":"2032-06-26","underlying":"Common Stock","underlying_shares":19000},"source":{"system":"sec-edgar","filing":"0000899243-22-024524","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1239746/000089924322024524/doc4.xml","form_type":"4"}},{"id":2219363,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":32842,"kind":"person","name":"Gould Robert J","position":1,"cik":"0001577034","reported_name":"Gould Robert J","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T21:00:44.000Z","date":"2022-06-27","kind":"grant","acquired":true,"shares":19000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2022 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":19000,"derivative":{"exercise_price":5.22,"expiration_date":"2032-06-26","underlying":"Common Stock","underlying_shares":19000},"source":{"system":"sec-edgar","filing":"0000899243-22-024527","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1577034/000089924322024527/doc4.xml","form_type":"4"}},{"id":2219170,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":29690,"kind":"person","name":"Dorton Katina","position":1,"cik":"0001617541","reported_name":"Dorton Katina","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T21:00:36.000Z","date":"2022-06-27","kind":"grant","acquired":true,"shares":19000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2022 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":19000,"derivative":{"exercise_price":5.22,"expiration_date":"2032-06-26","underlying":"Common Stock","underlying_shares":19000},"source":{"system":"sec-edgar","filing":"0000899243-22-024526","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1617541/000089924322024526/doc4.xml","form_type":"4"}},{"id":2219620,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":33367,"kind":"person","name":"Banks Sonja","position":1,"cik":"0001896415","reported_name":"Banks Sonja","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T21:00:31.000Z","date":"2022-06-27","kind":"grant","acquired":true,"shares":19000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2022 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":19000,"derivative":{"exercise_price":5.22,"expiration_date":"2032-06-26","underlying":"Common Stock","underlying_shares":19000},"source":{"system":"sec-edgar","filing":"0000899243-22-024523","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1896415/000089924322024523/doc4.xml","form_type":"4"}},{"id":2219407,"issuer":{"id":5969,"kind":"organization","name":"Fulcrum Therapeutics, Inc."},"owners":[{"id":78050,"kind":"person","name":"Collins James J.","position":1,"cik":"0001779269","reported_name":"Collins James J.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2022-06-29T17:00:18.000Z","date":"2022-06-27","kind":"grant","acquired":true,"shares":19000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option was granted on June 27, 2022 and is scheduled to vest with respect to all shares on the first anniversary of the grant date or, if earlier, immediately prior to the first annual meeting of stockholders occurring after the grant date, subject to continued service."}],"balance_after":19000,"derivative":{"exercise_price":5.22,"expiration_date":"2032-06-26","underlying":"Common Stock","underlying_shares":19000},"source":{"system":"sec-edgar","filing":"0000899243-22-024522","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1779269/000089924322024522/doc4.xml","form_type":"4"}}],"next_cursor":"2022-06-29T17:00:18.000000Z,2219407"}