Van Nuys Construction company Tutor Perini Corp. said a trust controlled by Chairman and Chief Executive Ronald N. Tutor plans to sell 4.5 million shares- nearly one-quarter of his stake in the company. Following this offering, Tutor will beneficially own 14.7 million shares of Tutor Perini’s common stock. The Ronald N. Tutor Separate Property Trust is required to keep at least 13.3 million, or 60 percent of the shares Tutor received in connection with the 2008 merger with Tutor-Saliba Corp. until Sept. 8, 2013. Tutor has also agreed not to sell any more stock for 90 days after the offering.