[SCHEDULE 13G] Alto Neuroscience, Inc. SEC Filing

Rhea-AI Filing Summary

Perceptive Advisors LLC, Perceptive Life Sciences Master Fund, Ltd. and Joseph Edelman disclosed a 7.3% beneficial ownership stake in Alto Neuroscience, Inc. (ticker ANRO), representing 1,989,393 shares of common stock. The filing states the ownership percentage is calculated from 27,076,629 outstanding shares as of August 8, 2025. The Master Fund directly holds the shares while Perceptive Advisors acts as investment manager and Mr. Edelman is the managing member, so each reporting person reports shared voting and dispositive power over the same block. The filing certifies the position is not held to change or influence control of the issuer.

Positive

• Material disclosure: Reporting of a 7.3% stake ensures regulatory transparency for investors
• Single-block ownership: All reporting persons disclose the same 1,989,393 shares, reducing ambiguity about overlapping claims

Negative

• No sole voting or dispositive power reported, indicating limited unilateral influence over corporate decisions
• 7.3% stake may still exert market influence without a control intent, creating potential activist interest or trading volatility

Insights

Institutional Investor Analyst

Perceptive reports a material >5% passive stake and shared control of 1.99M shares.

The reported 1,989,393 shares equal 7.3% of the outstanding common stock based on 27,076,629 shares as of August 8, 2025, which meets the disclosure threshold requiring a Schedule 13G.

This position is described as shared voting and dispositive power and certified as not acquired to change control, indicating a likely passive or investment-management holding. Investors should note the holding is large enough to be a visible institutional stake but the filers disclaim a control intent in the near term.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

Alto Neuroscience, Inc.

(Name of Issuer)

Common Stock, $0.0001 par value per share

(Title of Class of Securities)

02157Q109

(CUSIP Number)

10/03/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 02157Q109

1

Names of Reporting Persons

Perceptive Advisors LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 1,989,393.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 1,989,393.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,989,393.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

7.3 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

CUSIP No. 02157Q109

1

Names of Reporting Persons

Joseph Edelman

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 1,989,393.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 1,989,393.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,989,393.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

7.3 %

12

Type of Reporting Person (See Instructions)

IN

SCHEDULE 13G

CUSIP No. 02157Q109

1

Names of Reporting Persons

Perceptive Life Sciences Master Fund, Ltd.

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 1,989,393.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 1,989,393.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,989,393.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

7.3 %

12

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Alto Neuroscience, Inc.
(b)	Address of issuer's principal executive offices: 650 Castro Street, Suite 450, Mountain View, CA
Item 2.
(a)	Name of person filing: The names of the persons filing this report (collectively, the "Reporting Persons") with respect to shares of Common Stock, $0.0001 par value per share (the "Common Stock") of Alto Neuroscience, Inc. (the "Issuer") are: Perceptive Advisors LLC ("Perceptive Advisors") Joseph Edelman ("Mr. Edelman") Perceptive Life Sciences Master Fund, Ltd. (the "Master Fund")
(b)	Address or principal business office or, if none, residence: The address of the principal business office of each of the Reporting Persons is: 51 Astor Place, 10th Floor New York, NY 10003
(c)	Citizenship: Perceptive Advisors is a Delaware limited liability company Mr. Edelman is a United States citizen The Master Fund is a Cayman Islands corporation
(d)	Title of class of securities: Common Stock, $0.0001 par value per share
(e)	CUSIP No.: 02157Q109
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: The information required by this item with respect to each Reporting Person is set forth in Rows 5 through 9 and 11 of the cover pages to this Schedule 13G. The ownership percentages reported are based on 27,076,629 outstanding shares of Common Stock as of August 8, 2025, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on August 13, 2025. The Master Fund directly holds 1,989,393 shares of Common Stock. Perceptive Advisors serves as the investment manager to the Master Fund and may be deemed to beneficially own the securities directly held by the Master Fund. Mr. Edelman is the managing member of Perceptive Advisors and may be deemed to beneficially own the securities directly held by the Master Fund.
(b)	Percent of class: Perceptive Advisors: 7.3% Mr. Edelman: 7.3% Master Fund: 7.3%
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: Perceptive Advisors: 0 Mr. Edelman: 0 Master Fund: 0
	(ii) Shared power to vote or to direct the vote: Perceptive Advisors: 1,989,393 Mr. Edelman: 1,989,393 Master Fund: 1,989,393
	(iii) Sole power to dispose or to direct the disposition of: Perceptive Advisors: 0 Mr. Edelman: 0 Master Fund: 0
	(iv) Shared power to dispose or to direct the disposition of: Perceptive Advisors: 1,989,393 Mr. Edelman: 1,989,393 Master Fund: 1,989,393
Item 5.	Ownership of 5 Percent or Less of a Class.
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Perceptive Advisors LLC

Signature:	/s/ Joseph Edelman
Name/Title:	Joseph Edelman, Managing Member
Date:	10/10/2025

Joseph Edelman

Signature:	/s/ Joseph Edelman
Name/Title:	Joseph Edelman
Date:	10/10/2025

Perceptive Life Sciences Master Fund, Ltd.

Signature:	/s/ Joseph Edelman
Name/Title:	Joseph Edelman, Managing Member
Date:	10/10/2025

FAQ

What stake did Perceptive report in Alto Neuroscience (ANRO)?

Perceptive Advisors, Perceptive Life Sciences Master Fund and Joseph Edelman each reported beneficial ownership of 1,989,393 shares, equal to 7.3% of outstanding common stock.

How was the 7.3% ownership percentage calculated?

The percentage is based on 27,076,629 outstanding shares of common stock as of August 8, 2025.

Does the filing indicate Perceptive seeks control of ANRO?

No. The certification states the securities were not acquired to change or influence control and no control intent is indicated.

Who holds voting and disposal power for the reported shares?

The Master Fund directly holds the shares; Perceptive Advisors and Joseph Edelman report shared voting and shared dispositive power over the same 1,989,393 shares.

When was the Schedule 13G signed?

The signatures are dated 10/10/2025.