Arcellx (ACLX): Paradigm BioCapital group files 13G/A showing 0% stake

Rhea-AI Filing Summary

Arcellx, Inc. received an amended Schedule 13G/A from Paradigm BioCapital entities and Senai Asefaw, M.D., stating that as of June 30, 2026, they no longer beneficially own Arcellx common stock. Each reporting person reports 0.00 shares with 0.0% of the class, and no sole or shared voting or dispositive power. The amendment reflects that their holdings have fallen to 5 percent or less of the class, ending their status as significant beneficial owners.

Key Figures

Shares beneficially owned: 0.00 shares Ownership percentage: 0.0% Date of event: June 30, 2026 +1 more

4 metrics

Shares beneficially owned 0.00 shares Each reporting person as of June 30, 2026

Ownership percentage 0.0% Each reporting person’s percent of Arcellx common stock

Date of event June 30, 2026 Date requiring the Schedule 13G/A amendment

Par value per share $0.001 Arcellx common stock par value per share

Key Terms

beneficial ownership, disclaims beneficial ownership, sole voting power, shared dispositive power

4 terms

beneficial ownership financial

"may be deemed to have beneficially owned the Common Stock"

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.

disclaims beneficial ownership financial

"Each Reporting Person disclaims beneficial ownership with respect to any Common Stock"

sole voting power financial

"5 | Sole Voting Power 0.00 6 | Shared Voting Power 0.00"

Sole voting power is the exclusive right to cast votes attached to a shareholder’s stock without needing approval from anyone else. Like holding the only remote control for a TV, it lets that holder decide corporate matters such as board members, mergers, and policy changes, making it important to investors because it concentrates control and can strongly influence a company’s strategy and the value of its shares.

shared dispositive power financial

"8 | Shared Dispositive Power 0.00 9 0.00"

FAQ

What does Arcellx (ACLX) disclose in this Schedule 13G/A amendment?

The filing reports that certain Paradigm BioCapital entities and Senai Asefaw, M.D. now hold 0.00 shares of Arcellx common stock, representing 0.0% of the class as of June 30, 2026.

Which investors are named in the Arcellx (ACLX) Schedule 13G/A amendment?

The reporting persons are Paradigm BioCapital Advisors LP, Paradigm BioCapital Advisors GP LLC, Senai Asefaw, M.D., and Paradigm BioCapital International Fund Ltd., collectively updating their beneficial ownership status in Arcellx.

What ownership percentage in Arcellx (ACLX) do the Paradigm entities now report?

Each reporting person states beneficial ownership of 0.0% of Arcellx common stock, with 0.00 shares owned and no sole or shared voting or dispositive power over any Arcellx shares.

As of what date is the Arcellx (ACLX) ownership information in this 13G/A effective?

The ownership information is stated as of the close of business on June 30, 2026, identified as the Date of Event that triggered this Schedule 13G/A amendment filing.

Do the Paradigm entities still have reporting obligations for Arcellx (ACLX) ownership?

They report ownership of 5 percent or less of the class, with 0.0% beneficial ownership, indicating they are no longer significant beneficial owners requiring large-position Schedule 13G reporting for Arcellx.

AI-generated analysis. How Rhea-AI works. Not financial advice.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Available on EDGAR 08/14/2026 - 04:29 PM Accepted by SEC EDGAR 08/14/2026 - 04:23 PM Learn about SEC filing dates

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 4)

Arcellx, Inc.

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

03940C100

(CUSIP Number)

06/30/2026

(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): 03940C100

1

Names of Reporting Persons

Paradigm BioCapital Advisors LP

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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0.0 %

12

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13G

CUSIP Number(s): 03940C100

1

Names of Reporting Persons

Paradigm BioCapital Advisors GP 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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0.0 %

12

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person: limited liability company

SCHEDULE 13G

CUSIP Number(s): 03940C100

1

Names of Reporting Persons

Senai Asefaw, M.D.

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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0.0 %

12

Type of Reporting Person (See Instructions)

IN

SCHEDULE 13G

CUSIP Number(s): 03940C100

1

Names of Reporting Persons

Paradigm BioCapital International 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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0.0 %

12

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Arcellx, Inc.
(b)	Address of issuer's principal executive offices: 800 Bridge Parkway, Redwood City, CA 94065
Item 2.
(a)	Name of person filing: This Schedule 13G is filed by the following (the "Reporting Persons"): (1) Paradigm BioCapital Advisors LP (the "Adviser"); (2) Paradigm BioCapital Advisors GP LLC (the "Adviser GP"); (3) Senai Asefaw, M.D. ("Senai Asefaw"); and (4) Paradigm BioCapital International Fund Ltd. (the "Fund"). The Fund is a private investment vehicle. The Fund and one or more separately managed accounts managed by the Adviser (the "Account") directly beneficially owned the Common Stock reported in the previously filed Schedule 13G. The Adviser is the investment manager of the Fund and the Account. The Adviser GP is the general partner of the Adviser. Senai Asefaw is the managing member of the Adviser GP. The Adviser, the Adviser GP and Senai Asefaw may be deemed to have beneficially owned the Common Stock that was directly beneficially owned by the Fund and the Account. Each Reporting Person disclaims beneficial ownership with respect to any Common Stock other than the Common Stock directly beneficially owned by such Reporting Person.
(b)	Address or principal business office or, if none, residence: The principal business office of the Fund is c/o Walkers, 190 Elgin Avenue, George Town, Grand Cayman KY1-9001, Cayman Islands. The principal business office of the Adviser, the Adviser GP and Senai Asefaw is 520 Fifth Avenue, 23rd Floor, New York, NY 10036.
(c)	Citizenship: For citizenship or place of organization see Item 4 of the cover page of each Reporting Person.
(d)	Title of class of securities: Common Stock, $0.001 par value per share
(e)	CUSIP No.: 03940C100
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: See Item 9 on the cover page for each Reporting Person, and Item 2, which information is given as of the close of business on June 30, 2026, the Date of Event which requires the filing of this Schedule 13G.
(b)	Percent of class: See Item 11 on the cover page for each Reporting Person.
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: See Item 5 on the cover page for each Reporting Person.
	(ii) Shared power to vote or to direct the vote: See Item 6 on the cover page for each Reporting Person.
	(iii) Sole power to dispose or to direct the disposition of: See Item 7 on the cover page for each Reporting Person.
	(iv) Shared power to dispose or to direct the disposition of: See Item 8 on the cover page for each Reporting Person.
Item 5.	Ownership of 5 Percent or Less of a Class.
	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.

Paradigm BioCapital Advisors LP

Signature:	/s/ David K. Kim
Name/Title:	David K. Kim / Authorized Signatory
Date:	08/14/2026

Paradigm BioCapital Advisors GP LLC

Signature:	/s/ David K. Kim
Name/Title:	David K. Kim / Authorized Signatory
Date:	08/14/2026

Senai Asefaw, M.D.

Signature:	/s/ Senai Asefaw, M.D.
Name/Title:	N/A
Date:	08/14/2026

Paradigm BioCapital International Fund Ltd.

Signature:	/s/ David K. Kim
Name/Title:	David K. Kim / Authorized Signatory
Date:	08/14/2026