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June 24 (Reuters) - Truck and engine maker Navistar International Corp said it adopted a tax asset protection plan to guard against any ownership changes that could hurt its ability to use net operating losses for tax relief.
The tax plan is designed to discourage any person or group from acquiring more than 4.99 percent of stake and would replace its existing poison pill takeover defense, the company said on Tuesday.
An ownership change under the Internal Revenue Code can occur when the percentage of one or more 5-percent shareholders increases by more than 50 percent at any time during the prior three years.
As of Oct. 31, Navistar had a federal net operating loss carryforward of about $1.8 billion, the company said.
The existing shareholders, with more than 4.99 percent stake, are exempt from the new tax plan unless they buy more shares.
Carl Ichan's Icahn Associates Corp has 17.63 percent ownership interest in Navistar, while Mark Rachesky's MHR Fund Management owned 17.20 percent as of April 2014.
The existing poison pill exempted any person or group from owning more than 19.99 percent of the company's common stock.
The plan, earlier set to expire on June 18, 2015, was last week amended to expire on July 1.
The tax plan will end on Sept. 1.
Navistar shares closed at $37.54 on the New York Stock Exchange on Monday.
(Reporting by Mridhula Raghavan in Bangalore; Editing by Sriraj Kalluvila)