Starbucks Corp shares jumped on Friday a day after billionaire investor Nelsol Peltz's Trian Fund disclosed its stake in the coffee retailer.

The fund bought 842,070 shares, or about one tenth of one percent of the company as of March 31, Trian Fund reported in a filing with the Securities and Exchange Commission on Thursday.

Peltz's fund also owns stakes in Wendy's International, Cheescake Factory, and Kraft Foods and Tiffany & Co.

Shares of Starbucks closed up 98 cents, or 6.08 percent to close at $17.05.

Peltz has been an activist investor at some of the firms he has owned. He pressured the board at Wendy's to sell off its Tim Hortons doughnut and coffee chain. Recently his fund acquired Wendy's.

Starbucks has recently been slowing its pace of expansion as competitors including McDonald's look to gain market share by offering similar premium coffee products.