Gilead fully acquires Arcellx (NASDAQ: ACLX) as tender offer and merger close

Rhea-AI Filing Summary

Gilead Sciences, Inc. has completed its acquisition of Arcellx, Inc. and now owns 100% of the company. A tender offer that expired on April 27, 2026 resulted in 38,795,604 Arcellx common shares being validly tendered and not withdrawn, representing approximately 77.2% of shares outstanding at expiration.

Following the offer, Gilead closed a merger under Section 251(h) of the DGCL, with Arcellx surviving as a wholly owned subsidiary. Each Arcellx share (with limited exceptions) was cancelled and converted into the right to receive a cash Closing Amount plus one contingent value right (CVR) per share. The 100 issued and outstanding shares of the purchaser’s common stock held by Gilead were converted into 100 new Arcellx shares, giving Gilead sole voting and dispositive power over all outstanding Arcellx stock. Arcellx shares ceased trading on the Nasdaq Global Select Market on April 28, 2026 and will be delisted and deregistered under the Exchange Act.

Insights

M&A and Corporate Actions Analyst

Gilead’s tender offer and short-form merger make Arcellx a wholly owned subsidiary and remove ACLX from public markets.

Gilead reports that 38,795,604 Arcellx shares were tendered, representing about 77.2% of shares outstanding at offer expiration. Using a Section 251(h) structure allowed Gilead to close the back-end merger without a separate Arcellx stockholder meeting, streamlining the change of control.

Each Arcellx common share, other than specified excluded categories, was converted into the right to receive a cash Closing Amount plus one contingent value right (CVR) per share, defining the economics for former public stockholders. After the transaction, Gilead holds 100 new Arcellx shares, representing all outstanding capital stock, and Arcellx will be delisted and deregistered, ending its status as a standalone public company.

Key Figures

Shares tendered in offer: 38,795,604 shares Tendered plus owned as % of class: 77.2% New Arcellx shares held by Gilead: 100 shares +3 more

6 metrics

Shares tendered in offer 38,795,604 shares Validly tendered and not withdrawn as of offer expiration

Tendered plus owned as % of class 77.2% Percentage of Arcellx shares outstanding at offer expiration

New Arcellx shares held by Gilead 100 shares All issued and outstanding Arcellx capital stock after merger

Sole voting power 100.00 shares Shares over which Gilead has sole voting power per cover page

Sole dispositive power 100.00 shares Shares over which Gilead has sole dispositive power per cover page

Percent of class owned 100% Percent of Arcellx common stock beneficially owned by Gilead

Key Terms

Merger Agreement, contingent value right (CVR), Section 251(h) of the DGCL, Offer Price, +2 more

6 terms

Merger Agreement financial

"As previously disclosed, Gilead, Purchaser and Arcellx entered into the Merger Agreement pursuant to which Purchaser commenced the Offer"

A merger agreement is a binding contract that lays out the exact terms for two companies to combine, including the price, what each side will deliver, and the conditions that must be met before the deal is completed. Investors care because it sets the timetable, payouts and risks — like a blueprint or prenup that shows whether the deal is likely to close, how ownership will change, and what could cancel or alter the payout they expect.

contingent value right (CVR) financial

"on a per Share basis, (x) the Closing Amount in cash ... plus (y) one CVR per Share"

A contingent value right (CVR) is a short-term claim given to shareholders as part of a corporate deal that pays out only if specific future milestones or targets are met, such as regulatory approval or sales thresholds. Think of it like a coupon that becomes redeemable only if the company clears a stated hurdle; it matters to investors because it preserves potential upside from uncertain outcomes while also carrying extra risk and separate market value from the main stock.

Section 251(h) of the DGCL regulatory

"without a meeting of the stockholders of Arcellx in accordance with Section 251(h) of the DGCL"

Offer Price financial

"the Closing Amount plus one CVR, together, the "Offer Price""

The offer price is the amount per share that a company or underwriter sets when selling new stock or bonds to investors, like the price tag on an item in a store. It matters because it determines how much investors must pay, shapes the initial market value of the security, and influences whether demand will be strong or weak — which affects early trading performance and potential returns.

Tender and Support Agreements financial

"At the effective time of the Merger, the Tender and Support Agreements terminated in accordance with their express terms."

beneficial owner financial

"Consequently, Gilead became the beneficial owner of such 100 New Shares"

A beneficial owner is the person who ultimately owns or controls a financial asset or property, even if their name isn't directly on official documents. Think of it like someone who secretly holds the keys to a safe deposit box—others may appear to have access, but the true owner is the one who benefits from what's inside. Identifying beneficial owners helps ensure transparency and prevent illegal activities like money laundering or fraud.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)

Arcellx, Inc.

(Name of Issuer)

Common Stock, par value $0.001

(Title of Class of Securities)

03940C100

(CUSIP Number)

Gilead Sciences, Inc.
333 Lakeside Drive,,
Foster City, CA, 94404
650-574-3000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

04/28/2026

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

schemaVersion:

SCHEDULE 13D

CUSIP Number(s): 03940C100

1

Name of reporting person

GILEAD SCIENCES, INC.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

WC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 100.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 100.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

100.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

100 %

14

Type of Reporting Person (See Instructions)

CO

Comment for Type of Reporting Person:

* See Item 4.

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Stock, par value $0.001
(b)	Name of Issuer: Arcellx, Inc.
(c)	Address of Issuer's Principal Executive Offices: 800 BRIDGE PARKWAY, REDWOOD CITY, CALIFORNIA , 94065.
Item 1 Comment: Explanatory Note This Amendment No. 1 amends the Schedule 13D filed on February 23, 2026, by Gilead Sciences, Inc. ("Gilead") relating to shares of common stock, par value $0.001 per share ("Shares" or "Common Stock") of Arcellx, Inc. (the "Original Schedule 13D"). Except as set forth herein, the Original Schedule 13D is unmodified. Capitalized terms used by not otherwise defined in this Amendment No. 1 have the meanings set forth in the Original Schedule 13D.
Item 4.	Purpose of Transaction
	Item 4 of the Original Schedule 13D is amended to include the following at the end thereof: "As previously disclosed, Gilead, Purchaser and Arcellx entered into the Merger Agreement pursuant to which Purchaser commenced the Offer on March 6, 2026. The Offer expired at 5:00 p.m., Eastern Time, on April 27, 2026. Computershare Trust Company N.A., the depositary and paying agent for the Offer, advised Gilead that, as of the expiration of the Offer, 38,795,604 Shares had been validly tendered and not validly withdrawn pursuant to the Offer, representing, together with Shares already owned by Gilead, approximately 77.2% of the Shares outstanding as of the expiration of the Offer. Following consummation of the Offer, on April 28, 2026, Gilead completed its acquisition of Arcellx through the merger of Purchaser with and into Arcellx, and without a meeting of the stockholders of Arcellx in accordance with Section 251(h) of the DGCL, with Arcellx surviving such Merger as a wholly owned subsidiary of Gilead. In connection with the Merger, each Share issued and outstanding immediately prior to the effective time of the Merger (other than (i) Shares owned immediately prior to the effective time of the Merger by Arcellx (including those held in Arcellx's treasury), (ii) Shares owned both as of the commencement of the Offer and immediately prior to the effective time of the Merger by Gilead, Purchaser or any other direct or indirect wholly owned subsidiary of Gilead, (iii) Shares irrevocably accepted for purchase pursuant to the Offer and (iv) Shares held by stockholders who are entitled to appraisal rights under Section 262 of the DGCL and have properly exercised and perfected their respective demands for appraisal of such Shares in the time and manner provided in Section 262 of the DGCL and, as of the effective time of the Merger, have neither effectively withdrawn nor lost their rights to such appraisal and payment under the DGCL) was cancelled and converted into the right to receive on a per Share basis, (x) the Closing Amount in cash, without any interest thereon, subject to any withholding tax, plus (y) one CVR per Share (the Closing Amount plus one CVR, together, the "Offer Price"). As a result of the Merger, the 100 issued and outstanding shares of common stock, par value $0.001 per share, of Purchaser held by Gilead were converted into 100 issued and outstanding shares of common stock, par value $0.001 per share (the "New Shares"), of Arcellx. Consequently, Gilead became the beneficial owner of such 100 New Shares, which represent all of Arcellx's issued and outstanding shares of capital stock. Following the Merger, all Shares ceased trading prior to the opening of trading on the Nasdaq Global Select Market on April 28, 2026, and will be delisted from Nasdaq and deregistered under the Exchange Act."
Item 5.	Interest in Securities of the Issuer
(a)	Item 5 of the Original Schedule 13D is hereby amended and restated in its entirety as follows: "(a)-(b) The information relating to the beneficial ownership of the Shares by Gilead set forth in Rows 7 through 13 on each of the cover pages hereto is incorporated by reference herein and is as of the date hereof. This Schedule 13D shall not be construed as an admission by Gilead that Gilead is, for the purposes of Section 13(d) of the Act, the beneficial owner of any Shares covered by this statement.
(b)	"(a)-(b) The information relating to the beneficial ownership of the Shares by Gilead set forth in Rows 7 through 13 on each of the cover pages hereto is incorporated by reference herein and is as of the date hereof. This Schedule 13D shall not be construed as an admission by Gilead that Gilead is, for the purposes of Section 13(d) of the Act, the beneficial owner of any Shares covered by this statement.
(c)	Except as otherwise described herein and in the Original Schedule 13D, neither Gilead nor, to the best knowledge of Gilead, any of the individuals listed on Schedule I have effected any transactions in Common Stock during the past sixty (60) days. On April 28, 2026, Purchaser accepted for payment pursuant to the Offer in exchange for the Offer Price all Shares validly tendered and not validly withdrawn pursuant to the Offer prior to the expiration of the Offer.
(d)	Not applicable.
(e)	Not applicable.
Item 6.	Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer
	Item 6 of the Original Schedule 13D is hereby amended and supplemented by adding the following at the end thereof: "At the effective time of the Merger, the Tender and Support Agreements terminated in accordance with their express terms."

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.

GILEAD SCIENCES, INC.

Signature:	/s/ Andrew D. Dickinson
Name/Title:	Andrew D. Dickinson / Chief Financial Officer
Date:	04/28/2026

FAQ

What does Gilead’s Schedule 13D/A say about its ownership of Arcellx (ACLX)?

The filing shows Gilead now beneficially owns 100 new Arcellx common shares, representing all of Arcellx’s issued and outstanding capital stock. Gilead reports sole voting and sole dispositive power over these 100 shares, giving it full control of Arcellx post-merger.

How many Arcellx (ACLX) shares were tendered to Gilead in the offer?

Gilead states that 38,795,604 Arcellx common shares were validly tendered and not validly withdrawn when the offer expired. These tendered shares, together with shares already owned by Gilead, represented approximately 77.2% of Arcellx’s outstanding shares at that time.

What consideration did Arcellx (ACLX) stockholders receive in the Gilead merger?

Each Arcellx share, with specified exceptions, was cancelled and converted into the right to receive a cash Closing Amount plus one contingent value right (CVR) per share. This combined cash-and-CVR package, defined as the Offer Price, replaced former public shareholders’ Arcellx common stock.

What legal structure did Gilead use to complete the Arcellx (ACLX) acquisition?

Gilead used a tender offer followed by a merger under Section 251(h) of the Delaware General Corporation Law. After the successful offer, Gilead merged its acquisition subsidiary into Arcellx without a separate Arcellx stockholder meeting, leaving Arcellx as a wholly owned subsidiary.

What happens to Arcellx (ACLX) stock trading and its Nasdaq listing after the merger?

The filing states that all Arcellx common shares ceased trading before the market opened on April 28, 2026. Arcellx’s shares will be delisted from the Nasdaq Global Select Market and deregistered under the Exchange Act, ending its status as a publicly traded company.

What are the Tender and Support Agreements mentioned in the Arcellx (ACLX) filing?

Tender and Support Agreements were arrangements with certain Arcellx stockholders to support Gilead’s transaction. The document explains that these agreements automatically terminated at the effective time of the merger, in accordance with their express terms, once Gilead completed its acquisition of Arcellx.