As of September 09, 2026, GCT Semiconductor Holding's top three insider holders are Inc. Anapass, (TenPercentOwner, 8.02Mn shares), Sponsor Group Iii Llc Concord (TenPercentOwner, 7.96Mn shares), Kyeongho Lee (Director, 1.10Mn shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Sponsor Group Iii Llc Concord | TenPercentOwner | 8,590,312 | 0 | 8,590,312 | 42.9% | 28 Mar, 2025 |
| 2 | Inc. Anapass, | TenPercentOwner | 8,017,466 | 0 | 8,017,466 | 40.0% | 27 Sep, 2024 |
| 3 | Kyeongho Lee | Director, Other | 1,096,122 | 0 | 1,096,122 | 5.5% | 02 Jul, 2026 |
| 4 | Hyunsoo Shin | Director, Other | 817,803 | 0 | 817,803 | 4.1% | 02 Jul, 2026 |
| 5 | Jeong-Min Kim | Chief Technology Officer | 302,701 | 0 | 302,701 | 1.5% | 22 Sep, 2025 |
| 6 | Edmond Cheng | Chief Financial Officer | 227,000 | 0 | 227,000 | 1.1% | 22 Sep, 2025 |
| 7 | John Schlaefer | President, Ceo Class Iii Dir | 202,728 | 0 | 202,728 | 1.0% | 30 Sep, 2025 |
| 8 | Alex Sum | Sr. Vp Of Sales And Marketing | 183,743 | 0 | 183,743 | 0.9% | 22 Sep, 2025 |
| 9 | Robert Barker | Director, Other | 155,445 | 0 | 155,445 | 0.8% | 02 Jul, 2026 |
| 10 | Jeffrey Tuder | Director, Other | 151,190 | 0 | 151,190 | 0.8% | 02 Jul, 2026 |
| 11 | Nelson Chan | Director, Other | 125,642 | 0 | 125,642 | 0.6% | 02 Apr, 2026 |
| 12 | Kukjin Chun | Director, Other | 102,371 | 0 | 102,371 | 0.5% | 02 Jul, 2026 |
| 13 | Peter Ort | Director | 30,000 | 0 | 30,000 | 0.1% | 17 Nov, 2023 |
| 14 | Lawrence E Leibowitz | Director | 30,000 | 0 | 30,000 | 0.1% | 17 Nov, 2023 |
| 15 | David Yoon | Vice President Of Finance | 8,204 | 0 | 8,204 | 0.0% | 27 Mar, 2024 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 30 Jun, 2026 | Robert Barker | Director, Other | Acquired A | 9,259 | $0.00 | $0 | 151,710 | Direct |
| 30 Jun, 2026 | Kyeongho Lee | Director, Other | Acquired A | 9,259 | $0.00 | $0 | 1,096,122 | Direct |
| 30 Jun, 2026 | Kukjin Chun | Director, Other | Acquired A | 9,259 | $0.00 | $0 | 98,636 | Direct |
| 30 Jun, 2026 | Hyunsoo Shin | Director, Other | Acquired A | 9,259 | $0.00 | $0 | 814,068 | Direct |
| 30 Jun, 2026 | Jeffrey Tuder | Director, Other | Acquired A | 9,259 | $0.00 | $0 | 151,190 | Direct |
| 31 Mar, 2026 | Hyunsoo Shin | Director, Other | Acquired A | 24,122 | $0.00 | $0 | 804,809 | Direct |
| 31 Mar, 2026 | Robert Barker | Director, Other | Acquired A | 24,122 | $0.00 | $0 | 142,451 | Direct |
| 31 Mar, 2026 | Kukjin Chun | Director, Other | Acquired A | 24,122 | $0.00 | $0 | 89,377 | Direct |
| 31 Mar, 2026 | Nelson Chan | Director, Other | Acquired A | 24,122 | $0.00 | $0 | 125,642 | Direct |
| 23 Feb, 2026 | Kukjin Chun | Director, Other | Disposed G | 40,000 | $0.00 | $0 | 65,255 | Direct |
| 31 Dec, 2025 | Nelson Chan | Director, Other | Acquired A | 22,916 | $0.00 | $0 | 101,520 | Direct |
| 31 Dec, 2025 | Hyunsoo Shin | Director, Other | Acquired A | 22,916 | $0.00 | $0 | 780,687 | Direct |
| 31 Dec, 2025 | Kukjin Chun | Director, Other | Acquired A | 22,916 | $0.00 | $0 | 105,255 | Direct |
| 31 Dec, 2025 | Robert Barker | Director, Other | Acquired A | 22,916 | $0.00 | $0 | 118,329 | Direct |
| 25 Nov, 2025 | Hyunsoo Shin | Director, Other | Acquired P | 16,725 | $1.28 | $21.41K | 757,771 | Direct |
| 20 Nov, 2025 | Hyunsoo Shin | Director, Other | Acquired P | 25,453 | $1.28 | $32.58K | 737,866 | Direct |
| 21 Nov, 2025 | Hyunsoo Shin | Director, Other | Acquired P | 3,180 | $1.28 | $4.07K | 741,046 | Direct |
| 30 Sep, 2025 | Hyunsoo Shin | Director, Other | Acquired A | 18,092 | $0.00 | $0 | 712,413 | Direct |
| 30 Sep, 2025 | Kukjin Chun | Director, Other | Acquired A | 18,092 | $0.00 | $0 | 82,339 | Direct |
| 30 Sep, 2025 | Robert Barker | Director, Other | Acquired A | 18,092 | $0.00 | $0 | 95,413 | Direct |