Oakland, Calif., attorney Dana Sack is glad he didn’t deposit that $360,400 check he got in the mail Jan. 30.

Since the start of the year, the real estate attorney has been contacted “out of nowhere” by eight companies, most from East Asia, asking for help collecting money they claimed to be owed by U.S. businesses. The inquiries came from well-known companies like Japan’s Tomen Corp. and Matila Manufacturing in Singapore. Sack signed fee agreements with four. “We were always in a position to say maybe this is a scam, but until they do something screwy, we should treat them honestly,” said Sack, of the five-lawyer Sack Rosendin firm. “We get a lot of calls off our advertising all the time.”