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The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the aggregrate number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":727667,"source":{"system":"sec-edgar","filing":"0001193125-26-214574","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1673991/000119312526214574/ownership.xml","form_type":"4"}},{"id":842978,"issuer":{"id":4247,"kind":"organization","name":"MBX Biosciences, Inc."},"owners":[{"id":48947,"kind":"person","name":"Hawryluk P. Kent","position":1,"cik":"0001673991","reported_name":"Hawryluk P. 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The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held by the P. Kent Hawryluk Revocable Trust dated January 25, 2011, of which the Reporting Person serves as trustee. The Reporting Person disclaims beneficial ownership except to the extent of any pecuniary interest therein, and this report shall not be deemed an admission that such shares are beneficially owned by him for Section 16 or any other purpose."}],"balance_after":486777,"source":{"system":"sec-edgar","filing":"0001193125-26-107268","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1673991/000119312526107268/ownership.xml","form_type":"4"}},{"id":878685,"issuer":{"id":4247,"kind":"organization","name":"MBX Biosciences, Inc."},"owners":[{"id":48947,"kind":"person","name":"Hawryluk P. Kent","position":1,"cik":"0001673991","reported_name":"Hawryluk P. 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The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held by the P. Kent Hawryluk Revocable Trust dated January 25, 2011, of which the Reporting Person serves as trustee. 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The Preferred Stock had no expiration date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock (collectively, the \"Preferred Stock\") was convertible into Common Stock on a one-for-12.0221 basis at any time at the option of the holder, and automatically converted into the number of shares shown in Column 7 immediately prior to the closing of the Issuer's initial public offering on September 16, 2024. The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock (collectively, the \"Preferred Stock\") was convertible into Common Stock on a one-for-12.0221 basis at any time at the option of the holder, and automatically converted into the number of shares shown in Column 7 immediately prior to the closing of the Issuer's initial public offering on September 16, 2024. 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The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock (collectively, the \"Preferred Stock\") was convertible into Common Stock on a one-for-12.0221 basis at any time at the option of the holder, and automatically converted into the number of shares shown in Column 7 immediately prior to the closing of the Issuer's initial public offering on September 16, 2024. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock (collectively, the \"Preferred Stock\") was convertible into Common Stock on a one-for-12.0221 basis at any time at the option of the holder, and automatically converted into the number of shares shown in Column 7 immediately prior to the closing of the Issuer's initial public offering on September 16, 2024. The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held by the P. Kent Hawryluk Revocable Trust dated January 25, 2011, of which the Reporting Person serves as trustee. The Reporting Person disclaims beneficial ownership except to the extent of any pecuniary interest therein, and this report shall not be deemed an admission that such shares are beneficially owned by him for Section 16 or any other purpose."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":28755},"source":{"system":"sec-edgar","filing":"0000950170-24-107527","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1673991/000095017024107527/ownership.xml","form_type":"4"}},{"id":1406074,"issuer":{"id":4247,"kind":"organization","name":"MBX Biosciences, Inc."},"owners":[{"id":48947,"kind":"person","name":"Hawryluk P. Kent","position":1,"cik":"0001673991","reported_name":"Hawryluk P. 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The Preferred Stock had no expiration date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Each share of Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock (collectively, the \"Preferred Stock\") was convertible into Common Stock on a one-for-12.0221 basis at any time at the option of the holder, and automatically converted into the number of shares shown in Column 7 immediately prior to the closing of the Issuer's initial public offering on September 16, 2024. The Preferred Stock had no expiration date."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each share of Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock (collectively, the \"Preferred Stock\") was convertible into Common Stock on a one-for-12.0221 basis at any time at the option of the holder, and automatically converted into the number of shares shown in Column 7 immediately prior to the closing of the Issuer's initial public offering on September 16, 2024. The Preferred Stock had no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each share of Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock (collectively, the \"Preferred Stock\") was convertible into Common Stock on a one-for-12.0221 basis at any time at the option of the holder, and automatically converted into the number of shares shown in Column 7 immediately prior to the closing of the Issuer's initial public offering on September 16, 2024. 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The Preferred Stock had no expiration date."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Shares held by the P. Kent Hawryluk Revocable Trust dated January 25, 2011, of which the Reporting Person serves as trustee. The Reporting Person disclaims beneficial ownership except to the extent of any pecuniary interest therein, and this report shall not be deemed an admission that such shares are beneficially owned by him for Section 16 or any other purpose."}],"balance_after":398277,"source":{"system":"sec-edgar","filing":"0000950170-24-107527","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1673991/000095017024107527/ownership.xml","form_type":"4"}},{"id":1406072,"issuer":{"id":4247,"kind":"organization","name":"MBX Biosciences, Inc."},"owners":[{"id":48947,"kind":"person","name":"Hawryluk P. 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The private placement is expected to close on March 15, 2017."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The shares of common stock and warrants were purchased as part of a private placement pursuant to a Securities Purchase Agreement whereby the Issuer sold units consisting of one share of the Issuer's common stock and a warrant to purchase 0.75 shares of the Issuer's common stock at a per unit price of $9.47. The private placement is expected to close on March 15, 2017."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"These shares are indirectly owned by the reporting person as trustee of the P. 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The private placement is expected to close on March 15, 2017."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The shares of common stock and warrants were purchased as part of a private placement pursuant to a Securities Purchase Agreement whereby the Issuer sold units consisting of one share of the Issuer's common stock and a warrant to purchase 0.75 shares of the Issuer's common stock at a per unit price of $9.47. The private placement is expected to close on March 15, 2017."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"These shares are indirectly owned by the reporting person as trustee of the P. 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