Interactive Brokers (IBKR) 4: Galik Milan sold 255,039 shares of Class A common stock at… (May 28, 2026)

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-05-08 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: Interactive Brokers Group, Inc. (IBKR) CIK: 0001381197 --- Reporting Owner --- Name: Galik Milan CIK: 0001391404 Role: Director, Officer (Chief Executive Officer) --- Non-Derivative Transactions --- [Transaction #1] Security: Class A common stock Date: 2026-05-08 | Code: F (Payment of exercise/tax) Shares: -255,039 | Price: $84.42 Total Value: $21,530,392.38 Shares Owned After: 3,215,389 | Ownership: D (Direct) Footnotes: [F1] The price represents the closing price of the issuer's Class A common stock as of May 8, 2026, the vesting date. [F2] This amount includes (a) Class A common stock attributable to vested restricted stock units that were awarded under the amended 2007 Stock Incentive Plan ("Plan") and (b) unvested restricted stock units that were awarded under the Plan. --- Footnotes (Complete Index) --- F1: The price represents the closing price of the issuer's Class A common stock as of May 8, 2026, the vesting date. F2: This amount includes (a) Class A common stock attributable to vested restricted stock units that were awarded under the amended 2007 Stock Incentive Plan ("Plan") and (b) unvested restricted stock units that were awarded under the Plan. --- Signature --- /s/ /s/ Raymond Bussiere as authorized signatory for Milan Galik (2026-05-28)