William Ackman, founder and CEO of hedge fund Pershing Square Capital Management, speaks to the audience about Herbalife company in New York in this July 22, 2014 file photo. Hedge fund Pershing ... more 
William Ackman, founder and CEO of hedge fund Pershing Square Capital Management, speaks to the audience about Herbalife company in New York in this July 22, 2014 file photo. Hedge fund Pershing Square Capital Management is pressing for seats on animal health company Zoetis Inc's board of directors, with an eye to pushing through cost cuts and a possible merger, according to sources familiar with the negotiations. REUTERS/Eduardo Munoz/Files (UNITED STATES - Tags: BUSINESS) less 
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Reuters | Photo By EDUARDO MUNOZ / REUTERS
Thu, Jan 29, 2015 4:07 PM EST