Wendy's shares are up almost 4 percent after Trian Fund Management increased its stake in the burger chain.
The 3.7 million share purchase gives Trian, led by activist investor and board member Nelson Peltz, more than 23 percent of Wendy's outstanding stock. Before the purchase, according to the data provider FactSet, Trian had about a 15 percent stake in the company.
In June of last year, Wendy's bought back about $1.4 billion of its stock from board members Peltz, Peter May and Edward Garden, along with investment funds managed by Trian. Trian is controlled by Peltz, May and Garden.
Shares of Wendy's Co., based in Dublin, Ohio, hit $13.49 in midday trading Wednesday, their highest point in nearly a decade.