The Securities and Exchange Commission launched a formal inquiry into whether Tyson Foods ( TSN) properly disclosed perquisites handed out to current and former top executives.

The country's largest meat processor said former senior chairman Don Tyson and current CEO John Tyson are among the executives upon which probe focuses. Don Tyson retired as the board's senior chairman in 2001 but remains on the board, to which he was appointed in 1952. John Tyson has been CEO since 2000.

"The SEC is seeking information primarily with respect to the disclosure of perquisites provided to certain directors and officers of the company," Tyson said in a statement. "The independent members of the board of directors have conducted a review of the matter. Based on this review, the company does not believe that the amounts involved are material to the company's financial position or results of operations."

The stock was recently down 57 cents, or 3%, to $17.53.