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As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and Spearhead Insurance Solutions IDF, LLC."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":4392637,"source":{"system":"sec-edgar","filing":"0001104659-25-062092","document":"tm2518715-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925062092/tm2518715-1_4seq1.xml","form_type":"4"}},{"id":1113851,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Put Option (obligation to buy)","published_at":"2025-06-12T16:51:24.000Z","date":"2025-05-16","kind":"other","planned":false,"acquired":false,"shares":178,"price":0,"value":0.0,"ownership":{"direct":false,"nature":"By Spearhead Insurance Solutions IDF, LLC"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and Spearhead Insurance Solutions IDF, LLC."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":0,"derivative":{"exercise_price":10,"exercise_date":"2025-04-03","expiration_date":"2025-05-16","underlying":"Common Stock","underlying_shares":17800},"source":{"system":"sec-edgar","filing":"0001104659-25-058955","document":"tm2517803-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925058955/tm2517803-1_4seq1.xml","form_type":"4"}},{"id":1113850,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Put Option (obligation to buy)","published_at":"2025-06-12T16:51:24.000Z","date":"2025-05-16","kind":"other","planned":false,"acquired":false,"shares":836,"price":0,"value":0.0,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and Spearhead Insurance Solutions IDF, LLC."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":0,"derivative":{"exercise_price":10,"exercise_date":"2025-04-03","expiration_date":"2025-05-16","underlying":"Common Stock","underlying_shares":83600},"source":{"system":"sec-edgar","filing":"0001104659-25-058955","document":"tm2517803-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925058955/tm2517803-1_4seq1.xml","form_type":"4"}},{"id":1113849,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Put Option (obligation to buy)","published_at":"2025-06-12T16:51:24.000Z","date":"2025-05-16","kind":"other","planned":false,"acquired":false,"shares":300,"price":0,"value":0.0,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and Spearhead Insurance Solutions IDF, LLC."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":0,"derivative":{"exercise_price":10,"exercise_date":"2025-02-27","expiration_date":"2025-05-16","underlying":"Common Stock","underlying_shares":30000},"source":{"system":"sec-edgar","filing":"0001104659-25-058955","document":"tm2517803-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925058955/tm2517803-1_4seq1.xml","form_type":"4"}},{"id":1173473,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Cash Settled Total Return Swaps","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"other","planned":false,"acquired":false,"shares":74333,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"kind","element":"transactionCoding","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"shares","element":"transactionShares","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"price","element":"transactionPricePerShare","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"In connection with the purchase of 74,333 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 74,333 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 50,000 shares."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":50000,"derivative":{"underlying":"Common Stock","underlying_shares":74333},"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":9,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}},{"id":1173472,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Cash-Settled Total Return Swaps","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"other","planned":false,"acquired":false,"shares":500000,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"kind","element":"transactionCoding","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"shares","element":"transactionShares","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"price","element":"transactionPricePerShare","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F6","text":"In connection with the purchase of 500,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 500,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 124,333 shares."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":124333,"derivative":{"underlying":"Common Stock","underlying_shares":500000},"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":8,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}},{"id":1173471,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Cash-Settled Total Return Swaps","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"other","planned":false,"acquired":false,"shares":325000,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"kind","element":"transactionCoding","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"shares","element":"transactionShares","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F5","text":"In connection with the purchase of 325,000 securities reported as being purchased in Table 1, ADAR1 Partners, LP and the counterparty to the cash-settled total equity swaps previously reported agreed to reduce the number of notional shares of Common Stock of the Issuer in the applicable basket by a corresponding number of 325,000 shares. As a result, the aggregate number of notional shares of Common Stock of the Issuer in the applicable basket after giving effect to such transactions is 624,333 shares."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":624333,"derivative":{"underlying":"Common Stock","underlying_shares":325000},"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":7,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}},{"id":1173470,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"purchase","planned":false,"acquired":true,"shares":74333,"price":10.33,"value":767859.89,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":4392737,"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}},{"id":1173469,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"purchase","planned":false,"acquired":true,"shares":500000,"price":10.33,"value":5165000.0,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":4318404,"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}},{"id":1173468,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"purchase","planned":false,"acquired":true,"shares":325000,"price":9.857,"value":3203525.0,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The reported price is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $9.13 to $10.60, inclusive."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":3818404,"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}},{"id":1173467,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"purchase","planned":false,"acquired":true,"shares":16365,"price":9.3952,"value":153752.448,"ownership":{"direct":false,"nature":"By Spearhead Insurance Solutions IDF, LLC"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The reported price is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $9.21 to $9.56, inclusive."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":743558,"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}},{"id":1173466,"issuer":{"id":6242,"kind":"organization","name":"Keros Therapeutics, Inc."},"owners":[{"id":980,"kind":"organization","name":"ADAR1 Capital Management, LLC","position":1,"cik":"0001940272","reported_name":"ADAR1 Capital Management, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74265,"kind":"organization","name":"ADAR1 Partners, LP","position":2,"cik":"0001758866","reported_name":"ADAR1 Partners, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":74266,"kind":"organization","name":"ADAR1 Capital Management GP, LLC","position":3,"cik":"0001940267","reported_name":"ADAR1 Capital Management GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":981,"kind":"person","name":"Schneeberger Daniel","position":4,"cik":"0001861120","reported_name":"Schneeberger Daniel","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-04-11T21:57:19.000Z","date":"2025-04-09","kind":"purchase","planned":false,"acquired":true,"shares":18560,"price":9.3952,"value":174374.912,"ownership":{"direct":false,"nature":"By ADAR1 Partners, LP"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The reported price is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $9.21 to $9.56, inclusive."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Mr. Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F8","text":"For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise."}],"balance_after":3493404,"source":{"system":"sec-edgar","filing":"0001104659-25-034321","document":"tm2512234-2_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1940267/000110465925034321/tm2512234-2_4seq1.xml","form_type":"4"}}]}