Sec Form 4 Filing - Hanley Jr. Michael Conick @ Alto Neuroscience, Inc. - 2025-07-03

FORM 4 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 Hanley Jr. Michael Conick 2. Issuer Name and Ticker or Trading Symbol Alto Neuroscience, Inc. [ ANRO] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) CHIEF OPERATING OFFICER (Last) (First) (Middle) C/O ALTO NEUROSCIENCE, INC., 650 CASTRO STREET, SUITE 450 3. Date of Earliest Transaction (MM/DD/YY) 07/03/2025 (Street) MOUTAIN 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 Employee Stock Option (Right to Buy) $ 2.35 07/03/2025 A 8,000 ( 1 ) 02/28/2034 Common Stock 8,000 ( 2 ) ( 3 ) 8,000 D Employee Stock Option (Right to Buy) $ 14.88 07/03/2025 D 8,000 ( 1 ) 02/28/2034 Common Stock 8,000 ( 2 ) ( 3 ) 0 D Employee Stock Option (Right to Buy) $ 2.35 07/03/2025 A 188,000 ( 4 ) 05/19/2034 Common Stock 188,000 ( 2 ) ( 3 ) 188,000 D Employee Stock Option (Right to Buy) $ 12.4 07/03/2025 D 188,000 ( 4 ) 05/19/2034 Common Stock 188,000 ( 2 ) ( 3 ) 0 D Employee Stock Option (Right to Buy) $ 2.35 07/03/2025 A 125,000 ( 5 ) 02/04/2035 Common Stock 125,000 ( 2 ) ( 3 ) 125,000 D Employee Stock Option (Right to Buy) $ 4.2 07/03/2025 D 125,000 ( 5 ) 02/04/2035 Common Stock 125,000 ( 2 ) ( 3 ) 0 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Hanley Jr. Michael Conick C/O ALTO NEUROSCIENCE, INC. 650 CASTRO STREET, SUITE 450 MOUTAIN VIEW, CA94041 CHIEF OPERATING OFFICER Signatures /s/ Erin R. McQuade, Attorney-in-Fact 07/08/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The shares subject to the option are fully vested and exercisable. ( 2 )The transactions reported herein reflect a one-time stock option repricing (the "Option Repricing") effective on July 3, 2025 (the "Repricing Date"). The Option Repricing applies to options with exercise prices greater than $2.35 per share held by continuing employees of the Issuer as of the Repricing Date. ( 3 )Pursuant to the Option Repricing, the exercise price of the repriced options has been amended to reduce the exercise price to $2.35 per share, the closing price of the Issuer's common stock on the Repricing Date. However, if an employee exercises a repriced option before the end of a retention period of one year (subject to earlier termination in certain circumstances), such employee will be required to pay the original exercise price per share of such repriced option. There is no change to the vesting schedules, expiration dates of, or number of shares underlying the repriced options. ( 4 )25% of the shares underlying the option vested on May 20, 2025, and one forty-eighth (1/48th) of the shares underlying the option vested or shall vest in monthly installments thereafter, subject to the Reporting Person's continuous service through each such vesting date. ( 5 )25% of the shares underlying the option shall vest on February 5, 2026, and one forty-eighth (1/48th) of the shares underlying the option shall vest in monthly installments thereafter, subject to the Reporting Person's continuous service through each such vesting date.

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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