For purposes of Section 280G, a change in control occurs when there’s an actual or effective change in control of the ownership or management of a corporation. This can include:
A person or group of persons acquiring ownership of more than 50% of the fair market value or voting power of a corporation
A change in ownership of a substantial portion of the assets of a corporation
A person or group of persons acquiring 20% of the voting power of a corporation in a 12-month period
A change in the majority of the board of directors in a 12-month period