A Japanese investor has bought 100 Wilshire Blvd.

The landmark 21-story office building in Santa Monica, Calif., was purchased from a subsidiary of Southmark Corporation, for an undisclosed sum, according to Bank of America’s Investment Real Estate Group, which serves as real estate investment adviser for the buyer. “During 1987, we expect Japanese investors to invest approximately $5 billion in U.S. real estate as the cost of property in Tokyo continues to zoom skyward,” said Jack S. Cooper, managing director of B of A’s Investment Real Estate Group.