A spokeswoman for Fox told the Boston Globe on Tuesday that Brown "is currently out of contract with the network."
The news will no doubt be seen as just the latest development that Brown is gearing up for a U.S. Senate bid in New Hampshire.
He announced in December that he's moving to the Granite State, calling it a "personal choice." Brown then re-launched his old campaign website last month with a message that seemed designed to foreshadow a campaign launch.
Brown joined Fox's stable of conservative analysts in February 2013, months after he lost his Massachusetts Senate seat to Elizabeth Warren.