GCTS

SEC source: 0000929638-26-003832 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 827,039

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.12 on September 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-003834 · form4.xml · nonDerivative · entry 1

Chun Kukjin · CIK 0002007838 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 111,607

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.12 on September 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-003836 · form4.xml · nonDerivative · entry 1

Chan Nelson · CIK 0001242653 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 147,872

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.12 on September 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-003838 · form4.xml · nonDerivative · entry 1

TUDER JEFFREY · CIK 0001671976 · Director · Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 164,161

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.12 on September 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-003840 · form4.xml · nonDerivative · entry 1

Barker Robert · CIK 0002007837 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 164,681

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.12 on September 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-003842 · form4.xml · nonDerivative · entry 1

Lee Kyeongho · CIK 0001542776 · Director · Chairman & Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,109,093

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.12 on September 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-003526 · form4.xml · nonDerivative · entry 1

Sum Alex · CIK 0001543349 · Sr. VP of Sales and Marketing

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 258,743

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 10, 2026 grant date, commencing September 10, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-26-003525 · form4.xml · nonDerivative · entry 1

Schlaefer John · CIK 0001542775 · Director · President, CEO & Class III Dir

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 352,728

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 10, 2026 grant date, commencing September 10, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-26-003524 · form4.xml · nonDerivative · entry 1

Kim Jeong-Min · CIK 0002007834 · Chief Technology Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 402,701

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 10, 2026 grant date, commencing September 10, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-26-003523 · form4.xml · nonDerivative · entry 1

Cheng Edmond · CIK 0001491155 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 296,000

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 10, 2026 grant date, commencing September 10, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-26-002495 · form4.xml · nonDerivative · entry 1

Barker Robert · CIK 0002007837 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 151,710

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.97 on June 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-002493 · form4.xml · nonDerivative · entry 1

Chan Nelson · CIK 0001242653 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 134,901

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.97 on June 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-002494 · form4.xml · nonDerivative · entry 1

Chun Kukjin · CIK 0002007838 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 98,636

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.97 on June 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-002492 · form4.xml · nonDerivative · entry 1

Lee Kyeongho · CIK 0001542776 · Director · Chairman & Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,096,122

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.97 on June 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-002491 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 814,068

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.97 on June 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-002547 · form4.xml · nonDerivative · entry 1

TUDER JEFFREY · CIK 0001671976 · Director · Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 151,190

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2026 through March 31, 2027 (beginning with the quarter ending June 30, 2026) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $2.97 on June 30, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2027, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-001389 · form4.xml · nonDerivative · entry 1

TUDER JEFFREY · CIK 0001671976 · Director · Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 141,931

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.14 on March 31, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-001360 · form4.xml · nonDerivative · entry 1

Lee Kyeongho · CIK 0001542776 · Director · Chairman & Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,086,863

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.14 on March 31, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-001359 · form4.xml · nonDerivative · entry 1

Chan Nelson · CIK 0001242653 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 125,642

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.14 on March 31, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-001358 · form4.xml · nonDerivative · entry 1

Chun Kukjin · CIK 0002007838 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 89,377

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.14 on March 31, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-001357 · form4.xml · nonDerivative · entry 1

Barker Robert · CIK 0002007837 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 142,451

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.14 on March 31, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-001356 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 804,809

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.14 on March 31, 2026, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-000929 · form4.xml · nonDerivative · entry 1

Chun Kukjin · CIK 0002007838 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 65,255

SEC source: 0000929638-26-000021 · form4.xml · nonDerivative · entry 1

TUDER JEFFREY · CIK 0001671976 · Director · Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 117,809

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.20 on December 31, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-000020 · form4.xml · nonDerivative · entry 1

Barker Robert · CIK 0002007837 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 118,329

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.20 on December 31, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-000019 · form4.xml · nonDerivative · entry 1

Chan Nelson · CIK 0001242653 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 101,520

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.20 on December 31, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-000018 · form4.xml · nonDerivative · entry 1

Chun Kukjin · CIK 0002007838 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 105,255

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.20 on December 31, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-000017 · form4.xml · nonDerivative · entry 1

Lee Kyeongho · CIK 0001542776 · Director · Chairman & Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,062,741

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.20 on December 31, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-26-000016 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 780,687

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.20 on December 31, 2025, rounded down to the nearest whole share.

F3 · shares: The RSU's will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-004392 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 757,771

SEC source: 0000929638-25-004362 · form4.xml · nonDerivative · entry 2

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 741,046

SEC source: 0000929638-25-004362 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 737,866

SEC source: 0000929638-25-003732 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 712,413

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.52 on September 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSU's will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-003731 · form4.xml · nonDerivative · entry 1

Lee Kyeongho · CIK 0001542776 · Director · Chairman & Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,039,825

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.52 on September 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-003730 · form4.xml · nonDerivative · entry 1

Chun Kukjin · CIK 0002007838 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 82,339

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.52 on September 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-003729 · form4.xml · nonDerivative · entry 1

Chan Nelson · CIK 0001242653 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 78,604

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.52 on September 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-003728 · form4.xml · nonDerivative · entry 1

Barker Robert · CIK 0002007837 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 95,413

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.52 on September 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-003799 · form4.xml · nonDerivative · entry 1

TUDER JEFFREY · CIK 0001671976 · Director · Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 94,893

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.52 on September 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-003689 · form4.xml · nonDerivative · entry 1

Schlaefer John · CIK 0001542775 · Director · President, CEO & Class III Dir

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 202,728

F1 · kind: The transaction is a distribution of 555 shares of Common Stock, for no consideration, by the Parakletos @ Venture Millennium Fund LP. to the Reporting Person.

SEC source: 0000929638-25-003563 · form4.xml · nonDerivative · entry 1

Kim Jeong-Min · CIK 0002007834 · Chief Technology Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 302,701

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 19, 2025 grant date, commencing September 19, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-25-003562 · form4.xml · nonDerivative · entry 1

Schlaefer John · CIK 0001542775 · Director · President, CEO & Class III Dir

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 202,173

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 19, 2025 grant date, commencing September 19, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-25-003561 · form4.xml · nonDerivative · entry 1

Cheng Edmond · CIK 0001491155 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 151,000

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 19, 2025 grant date, commencing September 19, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-25-003560 · form4.xml · nonDerivative · entry 1

Sum Alex · CIK 0001543349 · Sr. VP of Sales and Marketing

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 183,743

F1 · kind: Represents restricted stock units ("RSU"), which constitute a contingent right to receive one share of common stock, par value $0.0001 per share, of GCT Semiconductor Holding, Inc. The RSUs vest over four years in equal 25% installments on each anniversary of the September 19, 2025 grant date, commencing September 19, 2026, subject to the Reporting Person's continued service with the Issuer.

SEC source: 0000929638-25-003492 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 694,321

SEC source: 0000929638-25-003408 · form4.xml · nonDerivative · entry 2

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 650,254

SEC source: 0000929638-25-003408 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 639,954

SEC source: 0000929638-25-003096 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 631,704

SEC source: 0000929638-25-002498 · form4.xml · nonDerivative · entry 1

TUDER JEFFREY · CIK 0001671976 · Director · Class III Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 76,801

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.49 on June 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-002497 · form4.xml · nonDerivative · entry 1

Shin Hyunsoo · CIK 0002007757 · Director · Class II Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 510,704

F1 · shares: Represents Restricted Stock Units ("RSUs") acquired pursuant to the terms of the GCT Semiconductor Holding, Inc. (the "Issuer") GCT 2024 Omnibus Incentive Compensation Plan. Each RSU represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of the Issuer following vesting.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.49 on June 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSU's will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.

SEC source: 0000929638-25-002495 · form4.xml · nonDerivative · entry 1

Chun Kukjin · CIK 0002007838 · Director · Class I Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 64,247

F1 · shares: Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, par value $0.0001 per share ("Common Stock") of GCT Semiconductor Holding, Inc. (the "Issuer") following vesting. The RSUs become payable in Common Stock in accordance with a deferral election made by the reporting person.

F2 · shares: The number of shares subject to and issuable under the award is determined on the last day of each calendar quarter during the period April 1, 2025 through March 31, 2026 (beginning with the quarter ending June 30, 2025) by dividing $27,500 by the fair market value per share of Common Stock, which was determined to be $1.49 on June 30, 2025, rounded down to the nearest whole share.

F3 · shares: The RSUs will vest on March 31, 2026, subject to continued service through such date.

F4 · shares: No expiration date is applicable to restricted stock units.