BANKING/FINANCE

Stock in Westcorp, the holding company for Western Financial Savings Bank in Orange, began trading Monday on the American Stock Exchange in a company effort to expand and diversify the ownership of its shares.

In the first day, 7,400 shares traded hands, and the stock closed at $5.75 a share, up 12.5 cents from the first trade. The company’s stock had been trading over the counter on the National Assn. of Securities Dealers Automated Quotation system.

Fast-growing Westcorp had $1.6 billion in assets at the end of September and reported $7.7 million in net income for the first nine months.

As part of its move to the American Stock Exchange, the company also expects to reincorporate soon as a Delaware firm to take advantage of that state’s laws, which are usually more favorable toward companies, said Regan E. Kelley, a senior vice president.

Among the Delaware laws is one that gives directors and officers more protection from lawsuits than California law, Kelly said. Under Delaware law, he said, Westcorp hopes to attract highly qualified directors who, without protection of their personal assets, would not join the board.