Japanese law firms are scrambling to open offices throughout Asia as they chase corporate clients exploring opportunities in the region.

When Toridoll Corp., which operates the Marugame Seimen udon restaurants, including in the U.S. and Russia, inked a deal last year with a Chinese company to set up a joint venture, it enlisted the help of a Japanese law firm with an office in China.

"The presence of a (Japanese) law firm is reassuring as we can seek advice at any time," a Toridoll official said, referring to the hazards of doing business abroad.