Bill Ackman’s Pershing Square Capital Management LP purchased options giving it the right to buy 25 million shares of Procter & Gamble Co., while reducing its holdings of the actual stock by 68 percent.

Pershing Square slashed the number of shares held in P&G by 19 million, to 8.94 million in the quarter ending in June, according to a filing Wednesday. Including the call options, the company has exposure to about 33.9 million P&G shares, compared with 28.9 million in the previous quarter.

Ackman bought a $1.8 billion stake in P&G about a year ago and pushed for the replacement of Chief Executive Officer Bob McDonald, who stepped down in May. Investors sometimes use options as a way of tying up less cash to hold a stake, since they can be purchased for a fraction of the price of a common share.

P&G, based in Cincinnati, fell 0.9 percent to $80.48 at the close in New York. The shares have gained 19 percent this year.