Navistar International Corp. said its board adopted a stockholder rights plan to prevent “coercive takeover tactics.”

Hedge fund manager Mark Rachesky last week disclosed he controls a 13.6 percent stake in Navistar. His former mentor, billionaire investor Carl Icahn, owns 11.9 percent.

One preferred stock purchase right will be distributed as a dividend on each share held as of June 29, Navistar said in a statement. The rights are exercisable if a shareholder acquires 15 percent or more of common stock or starts a tender offer that would lead to a stake larger than 15 percent, the company said.

Navistar, based in Lisle, Illinois, this month lowered its annual profit forecast to a range of break-even to $2 a share as it copes with the repercussions of pursuing a emission-reduction technology that has prevented it from winning U.S. Environmental Protection Agency certification for its 13-liter engine.