Company: GCTS
Filing Date: 2025-03-26
Form Type: 424B3
Source: 0000929638-25-001279
Chunk: 208

Company: GCT Semiconductor Holding, Inc.
Filing Date: 2025-03-26
Form: 424B3
Chunk 208
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public information about the Company, and should describe fully those circumstances to the Chief Financial Officer or Chief Executive Officer. In the event the requester is a director or an executive officer, the requestor should also indicate whether he or she has effected any non-exempt “opposite-way” transactions within the past six months, and should be prepared to report the proposed transaction on an appropriate Form 4 or Form 5. The requestor should also be prepared to comply with SEC Rule 144 and file a Form 144, if necessary, at the time of any sale. The person must also notify the Chief Financial Officer or Chief Executive Officer within two business days following completion of the transaction.

#### VI.
Broker Interface Procedures

In the event the Company becomes subject to Section 16 of the Exchange Act, the accelerated reporting obligations for Section 16 reports require tight interface with brokers handling transactions for our executives and directors. We require that you provide a copy of this Addendum to your broker and such broker must agree that he or she:

Will not enter any orders for you (except for orders under pre-approved Rule 10b5-1 plans) without first:

verifying with the Company that your transaction was pre-cleared; and

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complying with the brokerage firm’s compliance procedures (e.g., Rule 144).

Report any transactions immediately to the Chief Financial Officer or the Company’s legal counsel via:

telephone; and

in writing via e-mail describing the details of every transaction involving Company Securities, including gifts, transfers, pledges, and all 10b5-1 transactions.

#### VII.
Blackout Periods

(a)Quarterly Blackout Periods.The Company’s announcement of its quarterly financial results almost always has the potential to have a material effect on the market for Company Securities. Therefore, to avoid even the appearance of trading while in possession of material nonpublic information, persons who are or may be expected to be aware of the Company’s quarterly financial results generally will not be pre-cleared to trade in Company Securities during the period beginning two weeks prior to the end of each fiscal quarter and ending after the second full business day following the earlier of the Company’s (i) issuance of its quarterly earnings release, or (ii) if applicable, filing of its periodic report for the corresponding quarter (or year in the case of a Form 20-F or Form 10-K, as applicable). Persons subject to these quarterly blackout periods include all directors, executive officers, key employees, all employees in