Neel Grover, who has overseen the growth of Buy.com to more than $800 million in annual estimated e-commerce sales as CEO since 2006, will leave the web-only retailer Sept. 1. Buy.com says that chief operating officer Greg Giraudi also will depart then.

Roger Andelin will succeed Grover as the top executive at Buy, although he will not be CEO. Andelin is a former Buy chief information officer who will rejoin Buy from his current position as CEO of social networking company I’m Inc. Andelin will have the title of president and chief technology officer.

Andelin, who was Buy’s chief information officer from 2002 to 2008, will oversee technology, development and finance.

Buy.com is a unit of Rakuten Inc., a Japan-based operator of online retail marketplaces that acquired Buy for $250 million in 2010. Rakuten has not said if it’s also seeking someone to fill the position of CEO.

Rakuten announced the pending resignations of Grover and Giraudi in a press release dated July 20 that was posted on Buy.com but not widely distributed. Grover did not immediately respond to a request for comment on the reasons and timing of his departure from the company.

Grover, who is a lawyer, joined Buy.com in 2001 as a board member and was named president in 2003 and chief operating officer in 2004. In 2006 he was named CEO to succeed company founder Scott Blum. Grover will remain on the Buy.com board of directors and also become a member of the parent company’s U.S. division, Rakuten USA.

In an interview today with Internet Retailer, Grover said he planned to remain actively involved with Rakuten, where in addition to his participation on the two company boards he is also chairman and co-founder of Vault, an online marketplace for consumer brands that Rakuten launched last weekend at Vau.lt. Vault, which Rakuten initially referred to as Vaniti, specializes in selling products from consumer fashion brands, including apparel and home décor products. The site also offers members previews of new products and access to private sales.

The retailer also announced that Buy.com’s chief marketing officer, Bernard Luthi, will add the title of chief operating officer after Giraudi’s departure, extending his overall responsibilities to include sales and operations. Luthi, who joined Buy.com in January, has 15 years of e-commerce experience. Prior to joining Buy, he was a senior vice president of marketing, merchandising and other areas at Newegg.com, No. 13 in the Internet Retailer Top 500. He has also worked in senior marketing positions at companies including PC Mall, No. 57 in the Top 500, and Ingram Micro.

Buy.com is No. 36 in the Internet Retailer Top 500. Buy.com had Internet Retailer-estimated sales of $805.0 million in 2011, up 31% from nearly $614.5 million in 2007. Buy offers some 14 million products from 7,000 retailers that sell through the Buy.com
marketplace, where Buy itself primarily sells computers and consumer electronics, Grover says.

Rakuten, which recently invested the social shopping site Pinterest.com, will also be considering additional investments for the U.S. market, Grover said in the interview, declining to provide more details. He notes that Rakuten USA may seek to follow in the footsteps of Rakuten in Japan, where the company has invested in a group of properties as diversified as a mobile payments company, a baseball team and online banking and online golf reservations companies. “We’re definitely interested in seeing what makes sense to invest in or acquire here in the U.S.,” he says.  

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