{"transactions":[{"id":691009,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Convertible Promissory Note","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":false,"shares":165519,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F4","text":"Reflects a convertible note that was convertible into shares of Common Stock of the Issuer. The convertible note had a maturity date of June 17, 2027. The principal amount of the convertible note together with any accrued but unpaid interest automatically converted into shares of Common Stock of the Issuer upon the closing of the Issuer's initial public offering at a conversion price equal to the initial public offering price of the Issuer's common stock."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"Reflects a convertible note that was convertible into shares of Common Stock of the Issuer. The convertible note had a maturity date of June 17, 2027. The principal amount of the convertible note together with any accrued but unpaid interest automatically converted into shares of Common Stock of the Issuer upon the closing of the Issuer's initial public offering at a conversion price equal to the initial public offering price of the Issuer's common stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"Reflects a convertible note that was convertible into shares of Common Stock of the Issuer. The convertible note had a maturity date of June 17, 2027. The principal amount of the convertible note together with any accrued but unpaid interest automatically converted into shares of Common Stock of the Issuer upon the closing of the Issuer's initial public offering at a conversion price equal to the initial public offering price of the Issuer's common stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"Reflects a convertible note that was convertible into shares of Common Stock of the Issuer. The convertible note had a maturity date of June 17, 2027. The principal amount of the convertible note together with any accrued but unpaid interest automatically converted into shares of Common Stock of the Issuer upon the closing of the Issuer's initial public offering at a conversion price equal to the initial public offering price of the Issuer's common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Shares held directly by Westlake BioPartners Fund II, L.P. (\"Fund II\"). The general partner of Fund II is Westlake BioPartners GP II, LLC (\"GP II\"). GP II may be deemed to share voting and dispositive power with regard to the shares held directly by Fund II. Seidenberg is the sole managing director of GP II and has voting and dispositive power over the shares held by Fund II. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":165519},"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":14,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691008,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series A-2 Convertible Preferred Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":false,"shares":2066857,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F5","text":"Shares held directly by Westlake BioPartners Opportunity Fund I, L.P. (\"Opportunity Fund\"). The general partner of Opportunity Fund is Westlake BioPartners Opportunity GP I, LLC (\"Opportunity GP\"). Opportunity GP may be deemed to share voting and dispositive power with regard to the shares held directly by Opportunity Fund. Seidenberg is the sole managing director of Opportunity GP and has voting and dispositive power over the shares held by Opportunity Fund. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":2066857},"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":13,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691007,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series B Convertible Preferred Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":false,"shares":1484401,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Shares held directly by Westlake BioPartners Fund II, L.P. (\"Fund II\"). The general partner of Fund II is Westlake BioPartners GP II, LLC (\"GP II\"). GP II may be deemed to share voting and dispositive power with regard to the shares held directly by Fund II. Seidenberg is the sole managing director of GP II and has voting and dispositive power over the shares held by Fund II. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":1484401},"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":12,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691006,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series A-2 Convertible Preferred Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":false,"shares":3464072,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Shares held directly by Westlake BioPartners Fund II, L.P. (\"Fund II\"). The general partner of Fund II is Westlake BioPartners GP II, LLC (\"GP II\"). GP II may be deemed to share voting and dispositive power with regard to the shares held directly by Fund II. Seidenberg is the sole managing director of GP II and has voting and dispositive power over the shares held by Fund II. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":3464072},"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":11,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691005,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series A-2 Convertible Preferred Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":false,"shares":1027635,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund I, L.P. (\"Fund I\"). The general partner of Fund I is Westlake BioPartners GP I, LLC (\"GP I\"). GP I may be deemed to share voting and dispositive power with regard to the shares held directly by Fund I. Beth Seidenberg (\"Seidenberg\") is the sole managing director of GP I and has voting and dispositive power over the shares held by Fund I. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":1027635},"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":10,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691004,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series A Convertible Preferred Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":false,"shares":3547842,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund I, L.P. (\"Fund I\"). The general partner of Fund I is Westlake BioPartners GP I, LLC (\"GP I\"). GP I may be deemed to share voting and dispositive power with regard to the shares held directly by Fund I. Beth Seidenberg (\"Seidenberg\") is the sole managing director of GP I and has voting and dispositive power over the shares held by Fund I. 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The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund I, L.P. (\"Fund I\"). The general partner of Fund I is Westlake BioPartners GP I, LLC (\"GP I\"). GP I may be deemed to share voting and dispositive power with regard to the shares held directly by Fund I. Beth Seidenberg (\"Seidenberg\") is the sole managing director of GP I and has voting and dispositive power over the shares held by Fund I. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":938979},"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":8,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691002,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":true,"shares":2066857,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F5","text":"Shares held directly by Westlake BioPartners Opportunity Fund I, L.P. (\"Opportunity Fund\"). The general partner of Opportunity Fund is Westlake BioPartners Opportunity GP I, LLC (\"Opportunity GP\"). Opportunity GP may be deemed to share voting and dispositive power with regard to the shares held directly by Opportunity Fund. Seidenberg is the sole managing director of Opportunity GP and has voting and dispositive power over the shares held by Opportunity Fund. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":2094813,"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":7,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691001,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":true,"shares":165519,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"Reflects a convertible note that was convertible into shares of Common Stock of the Issuer. The convertible note had a maturity date of June 17, 2027. The principal amount of the convertible note together with any accrued but unpaid interest automatically converted into shares of Common Stock of the Issuer upon the closing of the Issuer's initial public offering at a conversion price equal to the initial public offering price of the Issuer's common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Shares held directly by Westlake BioPartners Fund II, L.P. (\"Fund II\"). The general partner of Fund II is Westlake BioPartners GP II, LLC (\"GP II\"). GP II may be deemed to share voting and dispositive power with regard to the shares held directly by Fund II. Seidenberg is the sole managing director of GP II and has voting and dispositive power over the shares held by Fund II. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":5160847,"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":6,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":691000,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":true,"shares":1484401,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. 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Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":4995328,"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":690999,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":true,"shares":3464072,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. 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Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":3510927,"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":690998,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":true,"shares":1027635,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. 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Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":5944009,"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":690997,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":true,"shares":3547842,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund I, L.P. (\"Fund I\"). The general partner of Fund I is Westlake BioPartners GP I, LLC (\"GP I\"). GP I may be deemed to share voting and dispositive power with regard to the shares held directly by Fund I. Beth Seidenberg (\"Seidenberg\") is the sole managing director of GP I and has voting and dispositive power over the shares held by Fund I. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":4916374,"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":690996,"issuer":{"id":4709,"kind":"organization","name":"Latigo Biotherapeutics, Inc."},"owners":[{"id":24699,"kind":"organization","name":"Westlake BioPartners Fund I, L.P.","position":1,"cik":"0001749591","reported_name":"Westlake BioPartners Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24700,"kind":"organization","name":"Westlake BioPartners GP I, LLC","position":2,"cik":"0002007650","reported_name":"Westlake BioPartners GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":3,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":4,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24703,"kind":"organization","name":"Westlake BioPartners Opportunity Fund I, L.P.","position":5,"cik":"0001811946","reported_name":"Westlake BioPartners Opportunity Fund I, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24704,"kind":"organization","name":"Westlake BioPartners Opportunity GP I, LLC","position":6,"cik":"0001811945","reported_name":"Westlake BioPartners Opportunity GP I, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-08-11T10:00:58.000Z","date":"2026-08-10","kind":"exercise","planned":false,"acquired":true,"shares":938979,"ownership":{"direct":false,"nature":"See footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series Seed Convertible Preferred Stock, Series A Convertible Preferred Stock, Series A-2 Convertible Preferred Stock and Series B Convertible Preferred Stock (collectively, the \"Preferred Stock\") converted automatically into 1 share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. Share numbers give effect to such conversion. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund I, L.P. (\"Fund I\"). The general partner of Fund I is Westlake BioPartners GP I, LLC (\"GP I\"). GP I may be deemed to share voting and dispositive power with regard to the shares held directly by Fund I. Beth Seidenberg (\"Seidenberg\") is the sole managing director of GP I and has voting and dispositive power over the shares held by Fund I. Seidenberg disclaims Section 16 beneficial ownership of the shares reported herein except to the extent of her pecuniary interest therein, if any, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of any of the reported shares for purposes of Section 16 or any other purpose."}],"balance_after":1368532,"source":{"system":"sec-edgar","filing":"0001104659-26-093633","document":"tm2622668-1_4seq1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/2056611/000110465926093633/tm2622668-1_4seq1.xml","form_type":"4"}},{"id":1896427,"issuer":{"id":79310,"kind":"organization","name":"ACELYRIN, Inc.","symbol":"SLRN"},"owners":[{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":1,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":2,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":12102,"kind":"person","name":"Harper Sean E","position":3,"cik":"0001541946","reported_name":"Harper Sean E","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series C Redeemable Convertible Preferred Stock","published_at":"2023-05-11T21:16:01.000Z","date":"2023-05-09","kind":"exercise","planned":false,"acquired":false,"shares":2038148,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.underlying","element":"underlyingSecurityTitle","label":"F6","text":"Each share of Class A Common Stock was reclassified into one share of Common Stock immediately prior to the completion of the IPO."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund II, L.P., or Westlake Fund II. Westlake BioPartners GP II, LLC, or Westlake GP II, is the general partner of Westlake Fund II. Westlake GP II may be deemed to have sole voting and dispositive power with regard to the shares held directly by Westlake Fund II. Beth C. Seidenberg and Sean E. Harper are the Managing Directors of Westlake GP II and share voting and dispositive power over the shares held by Westlake Fund II, each of whom disclaims beneficial ownership of the shares held by Westlake Fund II except to the extent of such person's pecuniary interest therein, if any."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F3","text":"This report on Form 4 is jointly filed by Westlake Fund II, Westlake GP II and Sean E. Harper. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the \"Exchange Act\"), except to the extent of such person's or entity's pecuniary interest therein, if any. Westlake Fund II has designated a representative, Beth C. Seidenberg, a Managing Director of Westlake GP II, to serve on the Issuer's board of directors. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for the purposes of Section 16 of the Exchange Act, or for any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":2038148},"source":{"system":"sec-edgar","filing":"0001209191-23-028886","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1541946/000120919123028886/doc4.xml","form_type":"4"}},{"id":1896426,"issuer":{"id":79310,"kind":"organization","name":"ACELYRIN, Inc.","symbol":"SLRN"},"owners":[{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":1,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":2,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":12102,"kind":"person","name":"Harper Sean E","position":3,"cik":"0001541946","reported_name":"Harper Sean E","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series B Redeemable Convertible Preferred Stock","published_at":"2023-05-11T21:16:01.000Z","date":"2023-05-09","kind":"exercise","planned":false,"acquired":false,"shares":2445786,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.underlying","element":"underlyingSecurityTitle","label":"F6","text":"Each share of Class A Common Stock was reclassified into one share of Common Stock immediately prior to the completion of the IPO."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund II, L.P., or Westlake Fund II. Westlake BioPartners GP II, LLC, or Westlake GP II, is the general partner of Westlake Fund II. Westlake GP II may be deemed to have sole voting and dispositive power with regard to the shares held directly by Westlake Fund II. Beth C. Seidenberg and Sean E. Harper are the Managing Directors of Westlake GP II and share voting and dispositive power over the shares held by Westlake Fund II, each of whom disclaims beneficial ownership of the shares held by Westlake Fund II except to the extent of such person's pecuniary interest therein, if any."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F3","text":"This report on Form 4 is jointly filed by Westlake Fund II, Westlake GP II and Sean E. Harper. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the \"Exchange Act\"), except to the extent of such person's or entity's pecuniary interest therein, if any. Westlake Fund II has designated a representative, Beth C. Seidenberg, a Managing Director of Westlake GP II, to serve on the Issuer's board of directors. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for the purposes of Section 16 of the Exchange Act, or for any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":2445786},"source":{"system":"sec-edgar","filing":"0001209191-23-028886","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1541946/000120919123028886/doc4.xml","form_type":"4"}},{"id":1896425,"issuer":{"id":79310,"kind":"organization","name":"ACELYRIN, Inc.","symbol":"SLRN"},"owners":[{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":1,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":2,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":12102,"kind":"person","name":"Harper Sean E","position":3,"cik":"0001541946","reported_name":"Harper Sean E","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Series A Redeemable Convertible Preferred Stock","published_at":"2023-05-11T21:16:01.000Z","date":"2023-05-09","kind":"exercise","planned":false,"acquired":false,"shares":4056795,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F5","text":"Each share of preferred stock is convertible into one share of Common Stock and has no expiration date. Immediately prior to the completion of the IPO, all shares of preferred stock automatically converted into shares of Common Stock."},{"field":"derivative.underlying","element":"underlyingSecurityTitle","label":"F6","text":"Each share of Class A Common Stock was reclassified into one share of Common Stock immediately prior to the completion of the IPO."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund II, L.P., or Westlake Fund II. Westlake BioPartners GP II, LLC, or Westlake GP II, is the general partner of Westlake Fund II. Westlake GP II may be deemed to have sole voting and dispositive power with regard to the shares held directly by Westlake Fund II. Beth C. Seidenberg and Sean E. Harper are the Managing Directors of Westlake GP II and share voting and dispositive power over the shares held by Westlake Fund II, each of whom disclaims beneficial ownership of the shares held by Westlake Fund II except to the extent of such person's pecuniary interest therein, if any."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F3","text":"This report on Form 4 is jointly filed by Westlake Fund II, Westlake GP II and Sean E. Harper. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the \"Exchange Act\"), except to the extent of such person's or entity's pecuniary interest therein, if any. Westlake Fund II has designated a representative, Beth C. Seidenberg, a Managing Director of Westlake GP II, to serve on the Issuer's board of directors. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for the purposes of Section 16 of the Exchange Act, or for any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":4056795},"source":{"system":"sec-edgar","filing":"0001209191-23-028886","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1541946/000120919123028886/doc4.xml","form_type":"4"}},{"id":1896424,"issuer":{"id":79310,"kind":"organization","name":"ACELYRIN, Inc.","symbol":"SLRN"},"owners":[{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":1,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":2,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":12102,"kind":"person","name":"Harper Sean E","position":3,"cik":"0001541946","reported_name":"Harper Sean E","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2023-05-11T21:16:01.000Z","date":"2023-05-09","kind":"purchase","planned":false,"acquired":true,"shares":1250000,"price":18,"value":22500000.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F4","text":"Represents shares of Common Stock purchased in the Issuer's initial public offering of Common Stock (the \"IPO\")."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund II, L.P., or Westlake Fund II. Westlake BioPartners GP II, LLC, or Westlake GP II, is the general partner of Westlake Fund II. Westlake GP II may be deemed to have sole voting and dispositive power with regard to the shares held directly by Westlake Fund II. Beth C. Seidenberg and Sean E. Harper are the Managing Directors of Westlake GP II and share voting and dispositive power over the shares held by Westlake Fund II, each of whom disclaims beneficial ownership of the shares held by Westlake Fund II except to the extent of such person's pecuniary interest therein, if any."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F3","text":"This report on Form 4 is jointly filed by Westlake Fund II, Westlake GP II and Sean E. Harper. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the \"Exchange Act\"), except to the extent of such person's or entity's pecuniary interest therein, if any. Westlake Fund II has designated a representative, Beth C. Seidenberg, a Managing Director of Westlake GP II, to serve on the Issuer's board of directors. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for the purposes of Section 16 of the Exchange Act, or for any other purpose."}],"balance_after":9790729,"source":{"system":"sec-edgar","filing":"0001209191-23-028886","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1541946/000120919123028886/doc4.xml","form_type":"4"}},{"id":1896423,"issuer":{"id":79310,"kind":"organization","name":"ACELYRIN, Inc.","symbol":"SLRN"},"owners":[{"id":24701,"kind":"organization","name":"Westlake BioPartners Fund II, L.P.","position":1,"cik":"0001811947","reported_name":"Westlake BioPartners Fund II, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":24702,"kind":"organization","name":"Westlake BioPartners GP II, LLC","position":2,"cik":"0001811948","reported_name":"Westlake BioPartners GP II, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":12102,"kind":"person","name":"Harper Sean E","position":3,"cik":"0001541946","reported_name":"Harper Sean E","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2023-05-11T21:16:01.000Z","date":"2023-05-09","kind":"exercise","planned":false,"acquired":true,"shares":8540729,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Represents shares of Common Stock received upon conversion of shares of the reported series of preferred stock on a one-for-one basis without payment of further consideration."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Represents shares of Common Stock received upon conversion of shares of the reported series of preferred stock on a one-for-one basis without payment of further consideration."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F2","text":"Shares held directly by Westlake BioPartners Fund II, L.P., or Westlake Fund II. Westlake BioPartners GP II, LLC, or Westlake GP II, is the general partner of Westlake Fund II. Westlake GP II may be deemed to have sole voting and dispositive power with regard to the shares held directly by Westlake Fund II. Beth C. Seidenberg and Sean E. Harper are the Managing Directors of Westlake GP II and share voting and dispositive power over the shares held by Westlake Fund II, each of whom disclaims beneficial ownership of the shares held by Westlake Fund II except to the extent of such person's pecuniary interest therein, if any."},{"field":"ownership.direct","element":"directOrIndirectOwnership","label":"F3","text":"This report on Form 4 is jointly filed by Westlake Fund II, Westlake GP II and Sean E. Harper. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the \"Exchange Act\"), except to the extent of such person's or entity's pecuniary interest therein, if any. Westlake Fund II has designated a representative, Beth C. Seidenberg, a Managing Director of Westlake GP II, to serve on the Issuer's board of directors. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for the purposes of Section 16 of the Exchange Act, or for any other purpose."}],"balance_after":8540729,"source":{"system":"sec-edgar","filing":"0001209191-23-028886","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1541946/000120919123028886/doc4.xml","form_type":"4"}}]}