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The pre-funded warrants have no expiration date"},{"field":"shares","element":"transactionShares","label":"F1","text":"The securities reported herein were issued to clirSPV LLC (\"clirSPV\") pursuant to a Securities Purchase Agreement, dated as of June 24, 2024, as amended on June 26, 2024 (as amended, the \"Purchase Agreement\"), by and among the Issuer and clirSPV, in connection with its participation right to purchase unregistered securities of the Issuer to maintain a 19.99% ownership percentage of the Issuer's outstanding shares of common stock on terms and conditions no different than those offered to other purchasers. Pursuant to the Purchase Agreement, the Issuer issued clirSPV an aggregate of (i) 3,350,000 shares of common stock, (ii) redeemable warrants to purchase up to 7,039,500 shares of common stock and (iii) pre-funded warrants to purchase up to 1,343,000 shares of common stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F6","text":"The pre-funded warrants are exercisable by clirSPV at any time on or after the date of the Purchase Agreement, or June 24, 2024, until fully exercised at an exercise price per share equal to $0.0001, subject to a 19.99% beneficial ownership blocker. The pre-funded warrants have no expiration date"},{"field":"derivative.expiration_date","element":"expirationDate","label":"F6","text":"The pre-funded warrants are exercisable by clirSPV at any time on or after the date of the Purchase Agreement, or June 24, 2024, until fully exercised at an exercise price per share equal to $0.0001, subject to a 19.99% beneficial ownership blocker. The pre-funded warrants have no expiration date"},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Mr. Hoffman is the managing member of GPclirSPV LLC which is the managing member of clirSPV, the owner of the shares of common stock. Mr. Hoffman disclaims beneficial ownership of these shares except to the extent of his pecuniary interest in clirSPV. Mr. Hoffman has direct ownership of none of the shares of common stock purchased and a total direct beneficial ownership of 237,464 shares of common stock. clirSPV has direct ownership of 3,350,000 shares of common stock purchased and total direct beneficial ownership of 9,539,857 shares of common stock. GPclirSPV LLC has no direct ownership of the shares purchased and total indirect beneficial ownership of 9,539,857 shares of common stock. Princeton Opportunity Management LLC has no direct ownership of shares purchased and total indirect beneficial ownership of 9,539,857 shares of common stock."}],"balance_after":1343000,"derivative":{"underlying":"Common Stock","underlying_shares":1343000},"source":{"system":"sec-edgar","filing":"0001104659-24-075270","document":"tm2418369-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465924075270/tm2418369-1_4seq1.xml","form_type":"4"}},{"id":1468770,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89506,"kind":"organization","name":"clirSPV LLC","position":2,"cik":"0001747304","reported_name":"clirSPV LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89507,"kind":"organization","name":"GPclirSPV LLC","position":3,"cik":"0001749087","reported_name":"GPclirSPV LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89508,"kind":"organization","name":"Princeton Opportunity Management LLC","position":4,"cik":"0001749086","reported_name":"Princeton Opportunity Management LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Redeemable Warrants to Purchase Common Stock","published_at":"2024-06-26T20:04:00.000Z","date":"2024-06-24","kind":"purchase","planned":false,"acquired":true,"shares":7039500,"price":0.01,"value":70395.0,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F5","text":"The redeemable warrants are exercisable by clirSPV at any time on or after six (6) months after the date of the Purchase Agreement, or December 24, 2024, until June 24, 2029 at an exercise price per share equal to $1.05, subject to a 19.99% beneficial ownership blocker."},{"field":"shares","element":"transactionShares","label":"F1","text":"The securities reported herein were issued to clirSPV LLC (\"clirSPV\") pursuant to a Securities Purchase Agreement, dated as of June 24, 2024, as amended on June 26, 2024 (as amended, the \"Purchase Agreement\"), by and among the Issuer and clirSPV, in connection with its participation right to purchase unregistered securities of the Issuer to maintain a 19.99% ownership percentage of the Issuer's outstanding shares of common stock on terms and conditions no different than those offered to other purchasers. Pursuant to the Purchase Agreement, the Issuer issued clirSPV an aggregate of (i) 3,350,000 shares of common stock, (ii) redeemable warrants to purchase up to 7,039,500 shares of common stock and (iii) pre-funded warrants to purchase up to 1,343,000 shares of common stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F5","text":"The redeemable warrants are exercisable by clirSPV at any time on or after six (6) months after the date of the Purchase Agreement, or December 24, 2024, until June 24, 2029 at an exercise price per share equal to $1.05, subject to a 19.99% beneficial ownership blocker."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F5","text":"The redeemable warrants are exercisable by clirSPV at any time on or after six (6) months after the date of the Purchase Agreement, or December 24, 2024, until June 24, 2029 at an exercise price per share equal to $1.05, subject to a 19.99% beneficial ownership blocker."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Mr. Hoffman is the managing member of GPclirSPV LLC which is the managing member of clirSPV, the owner of the shares of common stock. Mr. Hoffman disclaims beneficial ownership of these shares except to the extent of his pecuniary interest in clirSPV. Mr. Hoffman has direct ownership of none of the shares of common stock purchased and a total direct beneficial ownership of 237,464 shares of common stock. clirSPV has direct ownership of 3,350,000 shares of common stock purchased and total direct beneficial ownership of 9,539,857 shares of common stock. GPclirSPV LLC has no direct ownership of the shares purchased and total indirect beneficial ownership of 9,539,857 shares of common stock. Princeton Opportunity Management LLC has no direct ownership of shares purchased and total indirect beneficial ownership of 9,539,857 shares of common stock."}],"balance_after":7039500,"derivative":{"underlying":"Common Stock","underlying_shares":7039500},"source":{"system":"sec-edgar","filing":"0001104659-24-075270","document":"tm2418369-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465924075270/tm2418369-1_4seq1.xml","form_type":"4"}},{"id":1468769,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89506,"kind":"organization","name":"clirSPV LLC","position":2,"cik":"0001747304","reported_name":"clirSPV LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89507,"kind":"organization","name":"GPclirSPV LLC","position":3,"cik":"0001749087","reported_name":"GPclirSPV LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89508,"kind":"organization","name":"Princeton Opportunity Management LLC","position":4,"cik":"0001749086","reported_name":"Princeton Opportunity Management LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2024-06-26T20:04:00.000Z","date":"2024-06-24","kind":"purchase","planned":false,"acquired":true,"shares":3350000,"price":0.91,"value":3048500.0,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"The securities reported herein were issued to clirSPV LLC (\"clirSPV\") pursuant to a Securities Purchase Agreement, dated as of June 24, 2024, as amended on June 26, 2024 (as amended, the \"Purchase Agreement\"), by and among the Issuer and clirSPV, in connection with its participation right to purchase unregistered securities of the Issuer to maintain a 19.99% ownership percentage of the Issuer's outstanding shares of common stock on terms and conditions no different than those offered to other purchasers. Pursuant to the Purchase Agreement, the Issuer issued clirSPV an aggregate of (i) 3,350,000 shares of common stock, (ii) redeemable warrants to purchase up to 7,039,500 shares of common stock and (iii) pre-funded warrants to purchase up to 1,343,000 shares of common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Mr. Hoffman is the managing member of GPclirSPV LLC which is the managing member of clirSPV, the owner of the shares of common stock. Mr. Hoffman disclaims beneficial ownership of these shares except to the extent of his pecuniary interest in clirSPV. Mr. Hoffman has direct ownership of none of the shares of common stock purchased and a total direct beneficial ownership of 237,464 shares of common stock. clirSPV has direct ownership of 3,350,000 shares of common stock purchased and total direct beneficial ownership of 9,539,857 shares of common stock. GPclirSPV LLC has no direct ownership of the shares purchased and total indirect beneficial ownership of 9,539,857 shares of common stock. Princeton Opportunity Management LLC has no direct ownership of shares purchased and total indirect beneficial ownership of 9,539,857 shares of common stock."}],"balance_after":9539857,"source":{"system":"sec-edgar","filing":"0001104659-24-075270","document":"tm2418369-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465924075270/tm2418369-1_4seq1.xml","form_type":"4"}},{"id":1553725,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Restricted Stock Units","published_at":"2024-04-02T17:34:21.000Z","date":"2024-04-01","kind":"grant","planned":false,"acquired":true,"shares":20408,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"As compensation for services as a non-executive director during the quarter ending June 30, 2024, the reporting person was granted restricted stock units (\"RSUs\") under the ClearSign Technologies Corporation 2021 Equity Incentive Plan and each RSU represents a right to receive one share of common stock or the cash equivalent thereof."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"The RSUs will vest upon the first to occur of: (1) a Change in Control (as defined in the applicable RSU award agreement), (2) the reporting person's Disability (as defined in the applicable RSU award agreement); (3) the reporting person's death; or (4) the reporting person's separation from service."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F2","text":"The RSUs will vest upon the first to occur of: (1) a Change in Control (as defined in the applicable RSU award agreement), (2) the reporting person's Disability (as defined in the applicable RSU award agreement); (3) the reporting person's death; or (4) the reporting person's separation from service."}],"balance_after":224311,"derivative":{"underlying":"Common Stock","underlying_shares":20408},"source":{"system":"sec-edgar","filing":"0001104659-24-042669","document":"tm2410636-2_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465924042669/tm2410636-2_4seq1.xml","form_type":"4"}},{"id":1661856,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89506,"kind":"organization","name":"clirSPV LLC","position":2,"cik":"0001747304","reported_name":"clirSPV LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89507,"kind":"organization","name":"GPclirSPV LLC","position":3,"cik":"0001749087","reported_name":"GPclirSPV LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":89508,"kind":"organization","name":"Princeton Opportunity Management LLC","position":4,"cik":"0001749086","reported_name":"Princeton Opportunity Management LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock (CLIR)","published_at":"2024-02-02T18:58:33.000Z","date":"2024-02-01","kind":"other","planned":false,"acquired":false,"shares":1269705,"price":0,"value":0.0,"ownership":{"direct":false,"nature":"See Note"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Note: clirSPV LLC distributed 1,269,705 shares of ClearSign Technologies Corp. to certain of its members. To the knowledge of Mr. Hoffman, none of such members holds 5% or more of the Common Stock of ClearSign Technologies Corp. after such distribution."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Note: Mr. Hoffman is the managing member of GPclirSPV LLC which is the managing member of clirSPV LLC, the owner of the common stock. Mr. Hoffman disclaims beneficial ownership of these shares except to the extent of his pecuniary interest in clirSPV LLC. clirSPV LLC has distributed 1,269,705 shares of ClearSign Technologies Corp. to certain of its members pursuant to their rights to cause such distributions. clirSPV LLC has direct ownership of 6,189,857 shares of Common Stock. GPclirSPV, LLC has no direct ownership of the shares purchased and total indirect beneficial ownership of 6,189,857 shares of Common Stock. Princeton Opportunity Management LLC has no direct ownership of shares purchased and total indirect beneficial ownership of 6,189,857 shares of Common Stock"}],"balance_after":6189857,"source":{"system":"sec-edgar","filing":"0001014108-24-000005","document":"primary_doc.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000101410824000005/primary_doc.xml","form_type":"4"}},{"id":1692749,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Restricted Stock 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from service."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F2","text":"The RSUs will vest upon the first to occur of: (1) a Change in Control (as defined in the applicable RSU award agreement), (2) the reporting person's Disability (as defined in the applicable RSU award agreement); (3) the reporting person's death; or (4) the reporting person's separation from service."}],"balance_after":203903,"derivative":{"underlying":"Common Stock","underlying_shares":18691},"source":{"system":"sec-edgar","filing":"0001104659-24-000871","document":"tm241812-2_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465924000871/tm241812-2_4seq1.xml","form_type":"4"}},{"id":1765389,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston 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for services as a non-executive director during the quarter ending March 31, 2023, the reporting person was granted restricted stock units (\"RSUs\") under the ClearSign Technologies Corporation 2021 Equity Incentive Plan and each RSU represents a right to receive one share of common stock or the cash equivalent thereof."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"The RSUs will vest upon the first to occur of: (1) a Change in Control (as defined in the applicable RSU award agreement), (2) the reporting person's Disability (as defined in the applicable RSU award agreement); (3) the reporting peron's death; or (4) the reporting person's separation from service."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F2","text":"The RSUs will vest upon the first to occur of: (1) a Change in Control (as defined in the applicable RSU award agreement), (2) the reporting person's Disability (as defined in the applicable RSU award 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The reporting person is a non-executive director. As compensation for their services, each non- executive director was awarded options for shares of common stock having an exercise price of $0.54. The total number of option shares awarded was based on the services provided by the director. These services include Board participation, committee participation, committee chair responsibilities and lead director responsibilities, if any. The award was issued from the Issuer's 2011 Equity Incentive Plan."}],"balance_after":20000,"derivative":{"exercise_price":0.54,"exercise_date":"2020-05-18","expiration_date":"2030-05-18","underlying":"Common Stock","underlying_shares":20000},"source":{"system":"sec-edgar","filing":"0001104659-20-064278","document":"tm2020299d2_4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465920064278/tm2020299d2_4.xml","form_type":"4"}},{"id":3183768,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Option to Purchase Common Stock","published_at":"2020-04-03T18:33:10.000Z","date":"2020-04-01","kind":"grant","acquired":true,"shares":20000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"security","element":"securityTitle","label":"F1","text":"On April 1, 2020 the Issuer's board of directors approved compensation to be paid to the Issuer's non-executive directors for services provided to the Issuer during the period from January 1, 2020 to March 31, 2020. The reporting person is a non-executive director. As compensation for their services, each non-executive director was awarded options for shares of common stock having an exercise price of $0.72. The total number of option shares awarded was based on the services provided by the director. These services include Board participation, committee participation, committee chair responsibilities and lead director responsibilities, if any. The option was issued from the Issuer's 2011 Equity Incentive Plan. The right to exercise the option and purchase the option shares vested on the date of award."}],"balance_after":20000,"derivative":{"exercise_price":0.72,"exercise_date":"2020-04-01","expiration_date":"2030-04-01","underlying":"Common Stock","underlying_shares":20000},"source":{"system":"sec-edgar","filing":"0001104659-20-043278","document":"tm2014958-3_4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465920043278/tm2014958-3_4.xml","form_type":"4"}},{"id":3384666,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Option to Purchase Common Stock","published_at":"2019-10-31T16:31:16.000Z","date":"2019-05-09","kind":"grant","acquired":true,"shares":86500,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"On May 9, 2019 the Issuer's board of directors approved compensation to be paid to the Issuer's non-executive directors for services provided to the Issuer during 2019. The reporting person is an non-executive director. As compensation for their services, each non-executive director was awarded options for shares of common stock having an exercise price of $1.00. The total number of option shares awarded was based on the services provided by the director. These services include Board participation, committee participation, committee chair responsibilites and lead director responsibilities, if any. The shares of common stock are issued from the Company's 2011 Equity Incentive Plan. The right to purchase the option shares vests in equal increments as follows: the right to purchase 21,625 shares vested on May 9, 2019 and the right to purchase the remaining 64,875 shares will vest in equal increments on the last day of each calendar quarter."}],"balance_after":86500,"derivative":{"exercise_price":1,"expiration_date":"2029-04-01","underlying":"Common Stock","underlying_shares":86500},"source":{"system":"sec-edgar","filing":"0001104659-19-058379","document":"tm1921550-4_4aseq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000110465919058379/tm1921550-4_4aseq1.xml","form_type":"4/A","original_submission_date":"2019-05-13"}},{"id":3468307,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Option to Purchase Common Stock","published_at":"2019-07-03T17:23:01.000Z","date":"2019-06-30","kind":"grant","acquired":true,"shares":21625,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"date","element":"transactionDate","label":"F1","text":"On May 9, 2019 the Issuer's board of directors approved compensation to be paid to the Issuer's non-executive directors for services provided to the Issuer during 2019.  The reporting person is an non-executive director.  As compensation for their services, each non-executive director was awarded options for shares of common stock having an exercise price of $1.00.  The total number of option shares awarded was based on the services provided by the director.  These services include Board participation, committee participation, committee chair responsibilites and lead director responsibilities, if any. The right to purchase the common stock is earned in quarterly increments.  The option was issued from the Company's 2011 Equity Incentive Plan."}],"balance_after":43250,"derivative":{"exercise_price":1,"exercise_date":"2019-06-30","expiration_date":"2029-04-01","underlying":"Common Stock","underlying_shares":21625},"source":{"system":"sec-edgar","filing":"0001144204-19-033823","document":"tv524822_4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000114420419033823/tv524822_4.xml","form_type":"4"}},{"id":3530080,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Option to Purchase Common Stock","published_at":"2019-05-13T18:46:48.000Z","date":"2019-05-09","kind":"grant","acquired":true,"shares":21625,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"On May 9, 2019, the Issuer's board of directors approved compensation to be paid to the Issuer's non-executive directors for services provided to the Issuer during the first quarter of 2019.  The reporting person is a non-executive director.   The number of option shares awarded was based on the services provided by the director.  These services include, depending on the individual, Board participation, committee participation, committee chair responsibilities and lead director responsibilities, if any.  The shares of common stock are issued from the Company's 2011 Equity Incentive Plan."}],"balance_after":21625,"derivative":{"exercise_price":1,"expiration_date":"2029-04-01","underlying":"Common Stock","underlying_shares":21625},"source":{"system":"sec-edgar","filing":"0001144204-19-025695","document":"tv521421_4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000114420419025695/tv521421_4.xml","form_type":"4"}},{"id":3704362,"issuer":{"id":7487,"kind":"organization","name":"ClearSign Technologies Corp","symbol":"CLIR"},"owners":[{"id":89505,"kind":"person","name":"HOFFMAN Robert Thurston Sr","position":1,"cik":"0001748409","reported_name":"HOFFMAN Robert Thurston Sr","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock/CLIR","published_at":"2019-01-04T20:08:05.000Z","date":"2018-12-31","kind":"grant","acquired":true,"shares":13153,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"On May 3, 2018 the Issuer's board of directors approved annual compensation for the Issuer's non-executive directors. The reporting person is a non-executive director. As partial compensation for services provided to the Issuer during 2018, each non-executive director was granted 27,027 shares of common stock having a per share value of $1.85, the closing price of the Issuer's common stock on the date of grant. The common stock is earned in quarterly increments and is issued on the last business day of each calendar quarter. The shares of common stock are issued from the Company's 2011 Equity Incentive Plan. Mr Hoffman started service on the Board in July of 2018 and the number of shares of common stock reported represents compensation for the third and fourth quarters of 2018."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"On May 3, 2018 the Issuer's board of directors approved annual compensation for the Issuer's non-executive directors. The reporting person is a non-executive director. As partial compensation for services provided to the Issuer during 2018, each non-executive director was granted 27,027 shares of common stock having a per share value of $1.85, the closing price of the Issuer's common stock on the date of grant. The common stock is earned in quarterly increments and is issued on the last business day of each calendar quarter. The shares of common stock are issued from the Company's 2011 Equity Incentive Plan. Mr Hoffman started service on the Board in July of 2018 and the number of shares of common stock reported represents compensation for the third and fourth quarters of 2018."}],"balance_after":13153,"source":{"system":"sec-edgar","filing":"0001144204-19-000739","document":"tv510462_4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1748409/000114420419000739/tv510462_4.xml","form_type":"4"}}]}