Peltz aims to take control of Wendy’s board

Trian said it wants to increase the size of Wendy's board to 15 directors from 13, a letter sent to the company said. It would then push to get five of those seats in addition to the three it already has, giving it an eight-person majority if it wins.

In its letter, which also was filed with the Securities and Exchange Commission, Trian said it hopes the board's review will result in a sale, but it didn't specify whether it favors a particular price or proposal.

In a separate move, Carl Icahn on Monday reported a 2.7% stake in Alliance Data Systems and said he believes the stock is undervalued and he reserves the right to seek to have conversations with the management regarding the transaction with Blackstone.