Sanjay Parthasarathy, the Microsoft (NSDQ: MSFT) corporate vice president who oversees the company’s Startup Business Accelerator group—which was set up last year with the charter of building new businesses for the company—is leaving Microsoft, paidContent has learned. The announcement was made internally this week, although a spokeswoman said that Parthasarathy made the decision to retire late last year for personal reasons.

Two of the group’s projects—location-based information service MSN Direct and small business phone system Response Point—were hard hit in the company’s second round of layoffs in early May, although Microsoft says Parthasarathy’s departure is not related to the cutbacks. Other Startup Business Accelerator projects include notification service Microsoft Vine, which was announced in April.

Amit Mital, who is the corporate vice president in charge of Microsoft’s Unlimited Potential Group—which develops products for emerging markets—will also assume responsibility for the Startup Business Accelerator once Parthasarathy leaves in September. A spokeswoman says that the two groups have a “symbiotic relationship” and that the move “represents the next step in the evolution of both organizations and their focus on new business for the company.”

Parthasarathy has a long history at Microsoft, according to his Microsoft biography. Prior to leading the Startup Business Accelerator, he was in charge of “platform strategy and evangelism of the Microsoft platform to developers, IT professionals, students and partners.” He joined Microsoft in 1990.

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