The aerospace firm's shareholders approved the move, which was proposed by management in part to make hostile takeover attempts more difficult. The company said, however, that it knows of no current efforts to acquire Lockheed. The firm also announced that it is raising its quarterly dividend to 25 cents from 20 cents a share for stockholders of record on May 27. And Chairman Lawrence O. Kitchen said the company expects to exceed last year's profit of $401 million but would not predict by how much.