Alex Kochis, who was the director of Microsoft's Genuine Software program, announced his resignation in a New Year's Eve blog post titled "Happy New Year and Goodbye."
"Today is my last day at Microsoft," said Kochis, in the post.
In a P.S., Kochis said he intends to continue working to thwart software piracy, but did not disclose any specific plans.
"While I'm leaving Microsoft I don't intend to leave the anti-piracy space. Those of you who follow the subject are likely to see me pop up in the future under my own shingle," Kochis wrote.
Kochis' departure could be a blow to Redmond, as it comes at a time of rampant software counterfeiting—particularly in key growth markets like Asia-Pacific. The Business Software Alliance estimates that software vendors lost more than $50 billion globally in 2008 due to counterfeiting and piracy.
Under Kochis, Microsoft launched a series of initiatives to combat the problem, including beefed up authentication and activation processes and dozens of lawsuits against alleged software pirates, domestically and abroad.
Microsoft's Genuine Advantage program, however, also drew criticism in recent years following a series of widely publicized incidents in which consumers who had purchased legitimate copies of Windows fell victim to "false positives" that branded their software fake and prevented activation.
With his departure, Kochis joined a growing list of executives to leave Redmond in that past two years. The list includes former CFO Chris Liddell, former data center chief Debra Chrapaty, former Windows head Kevin Johnson, former Windows technical lead Rob Short, and former chief media officer Joanne Bradford.
Liddell last month was named chief financial officer at General Motors. Liddell was replaced as Microsoft's CFO by corporate VP Peter Klein.
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