@WalMartLabs has lost two of its original leaders. Venky Harinarayan and Anand Rajaraman have stepped down from their jobs at the retail chain’s research arm, which is charged with developing social and mobile commerce initiatives, and with generally making it easier for consumers to shop the web and stores.

Harinarayan and Rajaraman each held the titles of senior vice president, global e-commerce. And each was a founder of Kosmix Corp., a company whose technology searches and analyzes online social data, such as Twitter posts, to personalize web content. Wal-Mart Stores Inc. bought Kosmix in April 2011 and folded it into @WalMartLabs, whose launch was announced at the same time.

“Venky and Anand have made incredible contributions to Wal-Mart, but the most important legacy they leave behind is an impressive team, and an innovation engine that will be a permanent part of our company,” says Neil Ashe, president and CEO of Walmart global e-commerce.

The 200 employees who work for @WalMartLabs now report to Jeremy King, chief technology officer for Walmart global e-commerce, the chain says. “The plan is to hire up to 200 people within @WalmartLabs India as well,” a spokeswoman for the chain adds.

Walmart.com is No. 4 in the Internet Retailer Top 500 Guide.