GCT Semiconductor Holding, Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Check the appropriate box:

GCT Semiconductor Holding, Inc.

(Name of Registrant as Specified In Its Charter)

N/A

(Name of Person(s) Filing Proxy Statement if Other Than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

GCT Semiconductor Holding, Inc

San Jose, California 95131

Notice of Annual Meeting of Stockholders

To Be Held on September 18, 2025

You are cordially invited to attend an annual meeting of stockholders (the “Annual Meeting”) of GCT Semiconductor Holding, Inc. (“GCT,” “we,” “us,” or “our”) to be held on September 18, 2025, at 4:00 p.m. Pacific Time. The Annual Meeting will be held via live audiocast at https://www.cstproxy.com/gctsemi/2025 for the following purposes:

To elect two Class I directors to our Board of Directors to serve until our 2028 annual meeting of stockholders or until their successors are duly elected and qualified or until their earlier resignation or removal;

To ratify the appointment of BPM LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2025;

To approve, for purposes of complying with the rules of the New York Stock Exchange (“NYSE”), the issuance of shares of our common stock in excess of 19.99% of our outstanding common stock pursuant to our equity line of credit facility; and

To transact any other business as may properly come before the Annual Meeting or any adjournments or postponements thereof.

You can find more information about each of these items, including the nominees for directors, in the proxy statement accompanying this notice. The record date for the Annual Meeting is July 25, 2025. Only stockholders of record at the close of business on that date may vote at the meeting or any postponement or adjournment of the meeting. These materials are first being delivered to stockholders on or about August 4, 2025.

The Board of Directors recommends that you vote in favor of each of the nominees for director (Proposal 1) and in favor of Proposals 2 and 3, each as described in the accompanying proxy statement.

Under the rules of the Securities and Exchange Commission (the “SEC”), we have elected to provide access to our proxy materials by notifying you of the availability of our proxy materials on the internet. On or about August 4, 2025, we will release a Notice of Internet Availability of Proxy Materials to our stockholders informing them that our proxy statement, our annual report for the fiscal year ended December 31, 2024 and voting instructions for the Annual Meeting are available online on our website at https://investors.gctsemi.com and at https://www.cstproxy.com/gctsemi/2025.

The Annual Meeting will be held via live audiocast at https://www.cstproxy.com/gctsemi/2025. There will not be a physical location for our Annual Meeting, and you will not be able to attend the meeting in person.

You are cordially invited to attend the Annual Meeting via live audiocast. Whether or not you expect to virtually attend the Annual Meeting, please vote on the matters to be considered as promptly as possible to ensure your representation at the Annual Meeting. You may vote via the internet, by telephone, or by returning the enclosed proxy card. Even if you have voted by proxy, you may still vote held via live audiocast if you virtually attend the Annual Meeting by going to https://www.cstproxy.com/gctsemi/2025 and logging in using the 12-digit control number found on your proxy card or voting instruction form. Once you are admitted as a stockholder to the Annual Meeting, you may vote and ask questions by following the instructions available on the meeting website. Please note, however, that if your shares are held of record by a broker, bank, or other nominee and you wish to vote at the meeting, you must obtain a proxy issued in your name from that record holder. Your proxy is revocable in accordance with the procedures set forth in the proxy statement.

You are encouraged to log in to this website before the Annual Meeting begins. Online check-in will be available approximately 15 minutes before the meeting starts. If you encounter any difficulties accessing or participating in the meeting through the meeting website, please call the support team at the number listed on the website log-in screen.

By order of the Board of Directors

/s/ John Schlaefer

President and Chief Executive Officer

August 4, 2025

• Your vote is important, so please act today! *

Important Notice regarding the Availability of Proxy Materials

for the 2025 Annual Meeting of Stockholders of GCT Semiconductor Holding, Inc.

to be held on September 18, 2025

On or about August 4, 2025, the Notice of Annual Meeting of Stockholders, Proxy Statement, Proxy Card and Annual Report for the fiscal year ending December 31, 2024 may be accessed over the internet free of charge athttps://www.cstproxy.com/gctsemi/2025.

Whether or not you plan to attend the annual meeting, we encourage you to vote and submit your proxy via the internet, telephone, or mail. For additional instructions on voting by the internet or telephone, please refer to your proxy card. To vote and submit your proxy by mail, please complete, sign, and date the enclosed proxy card and return it in the enclosed envelope. If you attend the Annual Meeting, you may revoke your proxy and vote virtually. If you hold your shares through an account with a brokerage firm, bank, or other nominee, please follow the instructions you receive from your account manager to vote your shares.

Forward-Looking Statements

The Company cautions that any forward-looking statements (as such term is defined in the Private Securities Litigation Reform Act of 1995) contained in this Proxy Statement involve risks and uncertainties and are subject to change based on various important factors, many of which may be beyond the Company’s control. Words such as “approximate,” “outlook,” “estimate,” “project,” “plan,” “believe,” “expect,” “anticipate,” “intend,” “goal,” “should,” and similar expressions may identify forward-looking statements. The following factors, in addition to those disclosed in “ITEM 1A. RISK FACTORS” of our Annual Report on Form 10-K and in our other filings made with the SEC could cause actual results to differ materially from those expressed or implied in any of the forward-looking statements included in this Proxy Statement: the ability of the Company to develop its 5G products and generate revenue; the ability to enter into and meet the obligations under partnership and collaboration agreements; the ability of the Company to grow and manage growth profitability and retain its key employees; the Company's inability to anticipate the future market demands and future needs of its customers; the impact of component shortages, suppliers' lack of production capacity, natural disasters or pandemics on the Company's sourcing operations and supply chain; the Company's future capital requirements and sources and uses of cash; and the ability to implement business plans, forecasts, and other expectations, including the growth of the 5G market. There can be no assurance that the forward-looking statements included in this Proxy Statement will prove to be accurate, and new risks may emerge from time to time. Except as may be required by applicable law, the Company assumes no obligation to publicly update or revise our forward-looking statements even if experience or future changes make it clear that any projected results expressed or implied therein will not be realized.

Incorporation by Reference

The Report of the Audit Committee included herein shall be deemed soliciting material or filed with the SEC and neither of them shall be deemed incorporated by reference into any prior or future filings made by us under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (the “Exchange Act”), except to the extent that we specifically incorporate such information by reference.

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2290 North 1st Street, Suite 201 San Jose, California 95131

Proxy Statement for

2025 Annual Meeting of Stockholders

The Board of Directors (the “Board”) of GCT Semiconductor Holding, Inc., a Delaware corporation (“GCT,” “we,” “us,” or “our”), is soliciting your proxy to vote at the 2025 annual meeting of stockholders (the “Annual Meeting”) of GCT to be held via live audiocast at https://www.cstproxy.com/gctsemi/2025 on September 18, 2025, at 4:00 p.m. Pacific Time, including at any adjournments or postponements of the Annual Meeting. The Annual Meeting will be held in a virtual-only format. You are invited to attend and vote your shares electronically at the Annual Meeting and submit questions by following the instructions available on the meeting website.

You are encouraged to log in to the website above before the Annual Meeting begins. Online check-in will be available approximately 15 minutes before the meeting starts. If you encounter any difficulties accessing or participating in the Annual Meeting through the meeting website, please call the support team at the number listed on the website log-in screen.

We are mailing copies of the proxy materials, which include this proxy statement, a proxy card, and our annual report on Form 10-K for the fiscal year ended December 31, 2024, to stockholders beginning on or about August 4, 2025. You do not need to attend the Annual Meeting via live audiocast to vote your shares. Instead, you may vote your shares by proxy via the internet or by completing, signing, and returning the enclosed proxy card.