Amazon.com Inc. is betting that stores of the future won't have any clerks or registers. A company in Japan thinks it can get there first.

Signpost Corp., which has a staff of about 100, has already deployed its technology in a kiosk on the platform of a train station in Tokyo. It's an ideal testing ground: a small space no bigger than a bedroom with dedicated entry and exit points, and commuters in a hurry.

The shares of Signpost, which is planning to unveil a product deal with a major retail chain by the end of this year, climbed as much as 4.9 percent Thursday in early trading. That's the highest level since the company went public a year ago.