Sec Form 3 Filing - Tansey Casey M @ Heartflow, Inc. - 2025-08-07

FORM 3 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Tansey Casey M 2. Issuer Name and Ticker or Trading Symbol Heartflow, Inc. [ HTFL] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O HEARTFLOW, INC., 331 E. EVELYN AVENUE 3. Date of Earliest Transaction (MM/DD/YY) 08/07/2025 (Street) MOUNTAIN VIEW, CA94041 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Series B-1 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 220,052 ( 1 ) I By U.S. Venture Partners X, L.P. ( 2 ) Series B-1 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 330,078 ( 1 ) I By U.S. Venture Partners X, L.P. ( 2 ) Series B-1 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 10,560 ( 1 ) I By USVP X Affiliates, L.P. ( 2 ) Series B-1 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 7,040 ( 1 ) I By USVP X Affiliates, L.P ( 2 ) Series B-2 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 220,052 ( 1 ) I By U.S. Venture Partners X, L.P. ( 2 ) Series B-2 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 330,078 ( 1 ) I By U.S. Venture Partners X, L.P ( 2 ) Series B-2 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 10,560 ( 1 ) I By USVP X Affiliates, L.P. ( 2 ) Series B-2 Preferred Stock ( 1 ) ( 1 ) ( 1 ) Common Stock 7,040 ( 1 ) I By USVP X Affiliates, L.P ( 2 ) Series C Preferred Stock ( 3 ) ( 3 ) ( 3 ) Common Stock 665,623 ( 3 ) I By U.S. Venture Partners X, L.P ( 2 ) Series C Preferred Stock ( 3 ) ( 3 ) ( 3 ) Common Stock 21,295 ( 3 ) I By USVP X Affiliates, L.P ( 2 ) Series D Preferred Stock ( 4 ) ( 4 ) ( 4 ) Common Stock 10,106 ( 4 ) I By U.S. Venture Partners X, L.P. ( 2 ) Series D Preferred Stock ( 4 ) ( 4 ) ( 4 ) Common Stock 80,855 ( 4 ) I By U.S. Venture Partners X, L.P. ( 2 ) Series D Preferred Stock ( 4 ) ( 4 ) ( 4 ) Common Stock 323 ( 4 ) I By USVP X Affiliates, L.P. ( 2 ) Series D Preferred Stock ( 4 ) ( 4 ) ( 4 ) Common Stock 2,586 ( 4 ) I By USVP X Affiliates, L.P. ( 2 ) Series F Preferred Stock ( 5 ) ( 5 ) ( 5 ) Common Stock 1,164,179 ( 5 ) I By U.S. Venture Partners X, L.P. ( 2 ) Series F Preferred Stock ( 5 ) ( 5 ) ( 5 ) Common Stock 37,244 ( 5 ) I By USVP X Affiliates, L.P. ( 2 ) Convertible Promissory Note ( 6 ) ( 6 ) ( 6 ) Common Stock $ 786,399.92 I By U.S. Venture Partners X, L.P. ( 2 ) Convertible Promissory Note ( 7 ) ( 7 ) ( 7 ) Common Stock $ 25,158.3 I By USVP X Affiliates, L.P. ( 2 ) Convertible Promissory Note ( 8 ) ( 8 ) ( 8 ) Common Stock $ 250,000 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Tansey Casey M C/O HEARTFLOW, INC. 331 E. EVELYN AVENUE MOUNTAIN VIEW, CA94041 X Signatures /s/ Angela Ahmad, Attorney-in-Fact for Casey M. Tansey 08/07/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Each share of Series B-1 preferred stock and Series B-2 preferred stock is convertible on a 1-to-0.4031 basis into shares of Heartflow, Inc.'s ("Heartflow") common stock and has no expiration date. The Series B-1 preferred stock and Series B-2 preferred stock will automatically convert into the underlying shares of common stock upon the closing of Heartflow's initial public offering. The conversion rate gives effect to the 1-for-2.92 reverse stock split of Heartflow's common stock, which became effective on July 31, 2025. ( 2 )Presidio Management Group X, L.L.C. ("PMG X") is the general partner of U.S. Venture Partners X, L.P. and USVP X Affiliates, L.P. The Reporting Person, Steven M. Krausz, Richard W. Lewis, Jonathan D. Root and Irwin Federman are the managing members of PMG X, and share voting and dispositive power with respect to the shares held by U.S. Venture Partners X, L.P. and USVP X Affiliates, L.P. Each of the managing members of PMG X disclaims beneficial ownership of such holdings, except to the extent of their pecuniary interest in the shares, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose. ( 3 )Each share of Series C preferred stock is convertible on a 1-to-0.5764 basis into shares of Heartflow's common stock and has no expiration date. The Series C preferred stock will automatically convert into the underlying shares of common stock upon the closing of Heartflow's initial public offering. The conversion rate gives effect to the 1-for-2.92 reverse stock split of Heartflow's common stock, which became effective on July 31, 2025. ( 4 )Each share of Series D preferred stock is convertible on a 1-to-0.6467 basis into shares of Heartflow's common stock and has no expiration date. The Series D preferred stock will automatically convert into the underlying shares of common stock upon the closing of Heartflow's initial public offering. The conversion rate gives effect to the 1-for-2.92 reverse stock split of Heartflow's common stock, which became effective on July 31, 2025. ( 5 )Each share of Series F preferred stock is convertible on a 1-to-0.3425 basis into shares of Heartflow's common stock and has no expiration date. The Series F preferred stock will automatically convert into the underlying shares of common stock upon the closing of Heartflow's initial public offering. The conversion rate gives effect to the 1-for-2.92 reverse stock split of Heartflow's common stock, which became effective on July 31, 2025. ( 6 )Represents the outstanding principal amount of a convertible promissory note held by U.S. Venture Partners X, L.P., which will automatically convert upon consummation of Heartflow's initial public offering into shares of common stock at a conversion price of 80% of the price per share in Heartflow's initial public offering, subject to a valuation ceiling of $2.0 billion. These shares of common stock issuable upon conversion of the convertible promissory note have no expiration date. ( 7 )Represents the outstanding principal amount of a convertible promissory note held by USVP X Affiliates, L.P., which will automatically convert upon consummation of Heartflow's initial public offering into shares of common stock at a conversion price of 80% of the price per share in Heartflow's initial public offering, subject to a valuation ceiling of $2.0 billion. These shares of common stock issuable upon conversion of the convertible promissory note have no expiration date. ( 8 )Represents the outstanding principal amount of a convertible promissory note held by Mr. Tansey, which will automatically convert upon consummation of Heartflow's initial public offering into shares of common stock at a conversion price of 80% of the price per share in Heartflow's initial public offering, subject to a valuation ceiling of $2.0 billion. These shares of common stock issuable upon conversion of the convertible promissory note have no expiration date.

Remarks: Exhibit 24 - Power of Attorney.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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