Vanguard files Schedule 13G: ACAD (NASDAQ: ACAD) 8.78M shares, 5.15%

Rhea-AI Filing Summary

Vanguard Portfolio Management reports beneficial ownership of 8,781,007 shares of ACADIA Pharmaceuticals Inc Common Stock. The filing states this equals 5.15% of the class, with 109,362 shares subject to sole voting power and 8,781,007 shares subject to sole dispositive power as of 03/31/2026. The disclosure describes holdings managed across Vanguard Portfolio Management LLC and affiliated business divisions.

Insights

Institutional Ownership Analyst

Large passive stake reported: 8.78M shares, 5.15% of ACAD.

Vanguard Portfolio Management discloses beneficial ownership of 8,781,007 shares, representing 5.15% of ACAD common stock as of 03/31/2026. The filing attributes sole dispositive power to Vanguard entities while voting power is limited to 109,362 shares.

Institutional stake size is near the 5% reporting threshold but does not itself indicate intent to influence governance; subsequent filings would show any changes in voting alignment or director nominations.

Corporate Governance Specialist

Disclosure clarifies control structure across Vanguard affiliates.

The statement explains that dispositive authority is exercised by Vanguard Portfolio Management LLC and affiliated divisions, and that holdings include interests held for funds and managed accounts. The disclosure follows SEC Release No. 34-39538 attribution guidance.

Any governance impact depends on how the voting tranche (109,362 shares) is exercised relative to the larger dispositive position; monitor future proxy or Schedule 13D/A filings for activist or coordinated voting behavior.

Key Figures

Beneficially owned shares: 8,781,007 shares Percent of class: 5.15% Sole voting power: 109,362 shares +3 more

6 metrics

Beneficially owned shares 8,781,007 shares reported as of <date>03/31/2026</date>

Percent of class 5.15% percent of ACAD common stock

Sole voting power 109,362 shares shares with sole power to vote

Sole dispositive power 8,781,007 shares shares with sole power to dispose

Reporting period 03/31/2026 ownership as of date

Signature date 04/28/2026 signed by Head of Global Fund Administration

Key Terms

Schedule 13G, Beneficial ownership, Sole dispositive power, Investment Company Act

4 terms

Schedule 13G regulatory

"Vanguard Portfolio Management reports beneficial ownership of 8,781,007 shares"

A Schedule 13G is a formal document that investors file with the government when they acquire a large ownership stake in a company, usually for investment purposes rather than control. It helps keep the public informed about who owns significant parts of a company's shares, which can influence how the company is managed and how investors make decisions. Filing this schedule is important for transparency and understanding the ownership landscape of publicly traded companies.

Beneficial ownership financial

"Amount beneficially owned: 8781007 (b) Percent of class: 5.15 %"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

Sole dispositive power regulatory

"Sole power to dispose or to direct the disposition of: 8781007"

Sole dispositive power is the exclusive legal authority to decide what happens to a security — for example, whether to sell, transfer, or retain shares — without needing anyone else’s permission. Investors care because it signals who truly controls the economic outcome of an investment: like holding the only key to a safe, the holder can realize gains or losses and may trigger regulatory reporting, insider rules, or influence over corporate ownership.

Investment Company Act regulatory

"investment company registered under the Investment Company Act of 1940"

The Investment Company Act is a law that sets rules for businesses whose main activity is managing and selling pooled money, such as mutual funds and other investment funds. It matters to investors because it requires clear reporting, limits managers from putting their own interests ahead of clients, and mandates safekeeping and oversight of assets—similar to safety inspections and traffic rules that help keep shared vehicles reliable and trustworthy.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

ACADIA Pharmaceuticals Inc

(Name of Issuer)

Common Stock

(Title of Class of Securities)

004225108

(CUSIP Number)

03/31/2026

(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)

schemaVersion:

SCHEDULE 13G

CUSIP Number(s): 004225108

1

Names of Reporting Persons

Vanguard Portfolio Management

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

PENNSYLVANIA

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 109,362.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 8,781,007.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

8,781,007.00

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)

5.15 %

12

Type of Reporting Person (See Instructions)

IA

Comment for Type of Reporting Person: In accordance with SEC Release No. 34-39538 (January 12, 1998), this Schedule 13G reflects the securities beneficially owned, or deemed to be beneficially owned, by Vanguard Portfolio Management LLC and the following affiliates of Vanguard Portfolio Management LLC or business divisions of such affiliates: Vanguard Fiduciary Trust Company and Vanguard Global Advisers, LLC. This Schedule 13G includes securities held by Vanguard funds, or sleeves thereof, over which Vanguard Portfolio Management LLC exercises dispositive power, in addition to securities held by clients over which the affiliates or business divisions of such affiliates indicated above exercise dispositive and/or voting power. This Schedule 13G does not include securities, if any, beneficially owned by other subsidiaries or affiliates of Vanguard Portfolio Management LLC, or business divisions of such subsidiaries whose ownership of securities is disaggregated from that of the reporting business unit in accordance with such release.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: ACADIA Pharmaceuticals Inc
(b)	Address of issuer's principal executive offices: 12830 El Camino Real, Suite 400, San Diego, CA, 92130
Item 2.
(a)	Name of person filing: Vanguard Portfolio Management
(b)	Address or principal business office or, if none, residence: 100 Vanguard Blvd,, Malvern, PA, 19355
(c)	Citizenship: PA
(d)	Title of class of securities: Common Stock
(e)	CUSIP Number(s): 004225108
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: 8781007
(b)	Percent of class: 5.15 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 109362
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 8781007
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. Vanguard Portfolio Management, including investment companies registered under the Investment Company Act of 1940 and other managed accounts, have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities reported herein.No one other person's interest in the securities reported herein is more than 5%.
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 acquired and are held in the ordinary course of business and 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.

Vanguard Portfolio Management

Signature:	Ashley Grim
Name/Title:	Head of Global Fund Administration
Date:	04/28/2026

FAQ

How many ACAD shares does Vanguard report owning?

Vanguard reports beneficial ownership of 8,781,007 shares of ACAD common stock. The filing states this stake equals 5.15% of the class as of 03/31/2026, with dispositive authority held by Vanguard Portfolio Management and affiliates.

What voting and dispositive powers does Vanguard hold in ACAD?

The filing shows 109,362 shares under sole voting power and 8,781,007 shares under sole dispositive power. It indicates voting authority is small relative to dispositive power and that holdings span Vanguard-managed funds and accounts.

Does the Schedule 13G indicate Vanguard seeks control of ACAD?

No explicit control intent is stated in this Schedule 13G filing. The disclosure lists beneficial ownership and power allocations but does not assert plans to influence governance or nominate directors.

When was the Vanguard Schedule 13G for ACAD signed?

The filing is signed by Ashley Grim, Head of Global Fund Administration, with a signature date of 04/28/2026. The ownership figures are reported as of 03/31/2026 in the submission.