GSK (NYSE: GSK) completes $58 tender offer for RAPT, moves to short‑form merger

Rhea-AI Filing Summary

RAPT Therapeutics was acquired via a completed tender offer by Redrose Acquisition Co., GlaxoSmithKline LLC and GSK plc for $58.00 per share. The offer expired at one minute after 11:59 P.M. Eastern on March 2, 2026, and 30,137,567 Shares were validly tendered, representing 93.36% of issued and outstanding Shares as of that time.

Because the Minimum Condition was satisfied, Purchaser accepted the tendered Shares and will pay for them promptly. Under Section 251(h) of the DGCL, Ultimate Parent, Parent and Purchaser intend to effect the Merger without a stockholder meeting, delist the Shares from Nasdaq, and take steps to terminate registration and suspend reporting as promptly as practicable.

Positive

• Offer acceptance reached ~93.36%, enabling a short‑form merger under Section 251(h) and avoiding a stockholder meeting
• Cash consideration fixed at $58.00 per Share for all Shares validly tendered and accepted

Negative

• Shares will be delisted from Nasdaq and the company intends to suspend Exchange Act reporting, ending public-market trading and ongoing public disclosures

Insights

M&A Attorney

Completed tender offer paves way for a short‑form merger under Section 251(h).

The tender offer accepted 30,137,567 Shares (approximately 93.36%), satisfying the Minimum Condition and enabling a merger by short‑form conversion under Section 251(h) of the DGCL. The filing states the parties intend to complete the Merger "as promptly as practicable" without a stockholder meeting.

The principal regulatory/administrative steps disclosed are delisting from Nasdaq and termination of registration under the Exchange Act; timing is not specified beyond the quoted phrase. Subsequent filings will reflect the merger closing and any required post‑closing notice filings.

Investor Relations Specialist

Public float will cease trading and reporting after the Merger; shareholders will lose public-market access.

Following acceptance, the Offeror group intends to delist the Shares and suspend Exchange Act reporting "as promptly as practicable". Tendered shares accepted at $58.00 will be paid as described in the Offer materials.

Shareholders not tendering may be cashed out under the Merger terms; the filing does not state any alternative liquidity mechanism or timeline beyond the stated intent.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE TO

Tender Offer Statement under Section 14(d)(1) or 13(e)(1)

of the Securities Exchange Act of 1934

(Amendment No. 2)

RAPT THERAPEUTICS, INC.

(Name of Subject Company (Issuer))

REDROSE ACQUISITION CO.,

GLAXOSMITHKLINE LLC

and

GSK PLC

(Names of Filing Persons - Offerors)

Common Stock, Par Value $0.0001 Per Share

(Title of Class of Securities)

75382E208

(Cusip Number of Class of Securities)

David Rea

GlaxoSmithKline LLC

1250 South Collegeville Road

Collegeville, PA 19426

+1 215-219-7521

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications on Behalf of Filing Persons)

Copy to:

George Karafotias

Beth Troy

Allen Overy Shearman Sterling US LLP

599 Lexington Avenue

New York, New York 10022

Telephone: +1 (212) 848-4000

☐ Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

☒ Third-party tender offer subject to Rule 14d-1.

☐ Issuer tender offer subject to Rule 13e-4.

☐ Going-private transaction subject to Rule 13e-3.

☐ Amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: ☒

If applicable, check the appropriate box(es) below to designate the appropriate rule provision(s) relied upon:

☐ Rule 13e-4(i) (Cross-Border Issuer Tender Offer)

☐ Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)

This Amendment No. 2 (this “Amendment”) amends and supplements the Tender Offer Statement on Schedule TO filed by (i) GSK plc, a public limited company organized under the laws of England and Wales (“Ultimate Parent”), (ii) GlaxoSmithKline LLC, a Delaware limited liability company and an indirect wholly-owned subsidiary of Ultimate Parent (“Parent”), and (iii) Redrose Acquisition Co., a Delaware corporation (“Purchaser”) and a direct wholly-owned subsidiary of Parent on February 2, 2026 (together with any amendments and supplements thereto, including this Amendment, the “Schedule TO”), relating to the offer by Purchaser to purchase all of the outstanding shares of common stock, par value, $0.0001 per share (each, a “Share” and, collectively, the “Shares”), of RAPT Therapeutics, Inc., a Delaware corporation (the “Company”), for $58.00 per Share in cash (such amount or any higher amount per share paid pursuant to the Offer, being the “Offer Price”), without interest, subject to any applicable withholding taxes, and upon the terms and subject to the conditions set forth in the Offer to Purchase, dated February 2, 2026 (together with any amendments or supplements thereto, the “Offer to Purchase”) and in the accompanying letter of transmittal (together with any amendments or supplements thereto, the “Letter of Transmittal” which, together with the Offer to Purchase and other related materials, as they may be amended or supplemented from time to time, collectively constitute the “Offer”), copies of which are annexed to and filed with the Schedule TO as Exhibits (a)(1)(A) and (a)(1)(B), respectively.

All information contained in the Offer to Purchase (including Schedule I to the Offer to Purchase) and the accompanying Letter of Transmittal is hereby expressly incorporated herein by reference in response to Items 1 through 9 and Item 11 of this Schedule TO and is supplemented by the information specifically provided in this Amendment, except as otherwise set forth below. This Amendment should be read together with the Schedule TO. Capitalized terms used and not otherwise defined in this Amendment have the meanings given to such terms in the Offer to Purchase.

Items 1 through 9; Item 11.

The Offer to Purchase and Items 1 through 9 and Item 11 of the Schedule TO, to the extent such Items incorporate by reference the information contained in the Offer to Purchase, are hereby amended and supplemented as follows:

“The Offer and withdrawal rights expired, as scheduled, at one minute following 11:59 P.M., Eastern Time, on March 2, 2026 (such date and time, the “Expiration Time”), and was not extended. Purchaser was advised by the Depositary that, as of the Expiration Time, a total of 30,137,567 Shares had been validly tendered and not validly withdrawn pursuant to the Offer, representing approximately 93.36% of the issued and outstanding Shares as of the Expiration Time. Accordingly, the Minimum Condition has been satisfied.

All conditions to the Offer having been satisfied, Purchaser irrevocably accepted for payment, and will cause the Depositary to pay for, as promptly as practicable, all Shares validly tendered and not validly withdrawn pursuant to the Offer.

As a result of its acceptance of the Shares tendered pursuant to the Offer and in accordance with Section 251(h) of the DGCL, Purchaser owns a number of Shares that, together with the Shares owned by Parent and its wholly owned subsidiaries, is greater than the percentage of Shares that would be required to adopt the Merger Agreement by a vote of the stockholders of the Company. Pursuant to Section 251(h) of the DGCL, Ultimate Parent, Parent and Purchaser intend to complete the acquisition of the Company through the Merger, as promptly as practicable and without a meeting of stockholders of the Company, with the Company continuing as the surviving corporation in the Merger and a direct wholly owned subsidiary of Parent.

Following the consummation of the Merger, all Shares will be delisted from the Nasdaq. Ultimate Parent, Parent and Purchaser intend to take steps to cause the termination of the registration of the Shares under the Exchange Act and suspend all of the Company’s reporting obligations under the Exchange Act as promptly as practicable.”

2

SIGNATURES

After due inquiry and to the best knowledge and belief of the undersigned, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Date: March 3, 2026

GLAXOSMITHKLINE LLC
By:		/s/ Justin Huang
		Name: Justin Huang
		Title: Secretary
REDROSE ACQUISITION CO.
By:		/s/ Justin Huang
		Name: Justin Huang
		Title: Director, President and Secretary
GSK PLC
By:		/s/ David Redfern
		Name: David Redfern
		Title: Authorized Signatory

3

FAQ

What did GSK pay per share to acquire RAPT (RAPT)?

GSK paid $58.00 per share. The Offer Price for each Share was $58.00, paid in cash to holders of Shares validly tendered and accepted under the Offer.

How many RAPT shares were validly tendered in the offer?

30,137,567 Shares were validly tendered and not withdrawn. That number represented approximately 93.36% of issued and outstanding Shares as of the Expiration Time of March 2, 2026.

Will RAPT remain listed and continue SEC reporting after the transaction?

No. The filing states the Shares will be delisted from Nasdaq and registration terminated. Ultimate Parent, Parent and Purchaser intend to take steps to terminate registration under the Exchange Act and suspend reporting as promptly as practicable.

Will there be a stockholder meeting to approve the merger?

No stockholder meeting is planned for the Merger under Section 251(h). The parties intend to complete the acquisition through a short‑form Merger under Section 251(h) of the DGCL without a meeting of stockholders.

When did the tender offer expire and was it extended?

The Offer expired at one minute after 11:59 P.M. Eastern on March 2, 2026. The filing states the Offer expired as scheduled and was not extended, which triggered the acceptance procedures described.