"Accepting such a position violates the non-competition promise Lee made when he was hired as an executive," Microsoft said as it last night sued a former top search executive, Dr Kai-Fu Lee, for accepting the post of R&D director in Google's R&D center in China.

According to the UK newspaper The Guardian, Microsoft added: "As a senior executive, Dr Lee has direct knowledge of Microsoft's trade secrets concerning search technologies and China business strategies. He has accepted a position focused on the same set of technologies and strategies for a direct competitor in egregious violation of his explicit contractual obligations."

Earlier, reports The Guardian, "Google had bragged of its hiring, describing Dr Lee as a 'respected computer scientist and industry pioneer' who will 'lead the operation and serve as president of the company's fast growing Chinese operations.

As of this writing Google had not commented publicly on the suit.

Recently, Google was in the headlines for a less controversial recruitmen when they brought on board former eBay research director Louis Monier.

“The main reason for me to leave is that eBay does not absorb innovation at the pace I enjoy," said Monier, back in June, "and its focus is narrower than Google."

"So rather than chewing on variations of e-commerce for the next few years," Monier continued, "I’m very tempted to play with radically new stuff: satellites images, machine translation, ways to extract knowledge from giant bodies of data."

When asked in an interview exactly why he was jumping ship and leaving eBay for Google, Monier told a reporter:

"Frankly...I’m dying to peek under the hood and see the infrastructure they have created. For someone like me, it’s the ultimate Christmas toy.”

It is not known whether Dr Kai-Fu Lee has a similar motivation. Nor is it yet established who contacted whom, unlike the Monier hiring, where Monier himself said, on record: "I have known Larry and Sergei forever, I want to believe that I had a standing invitation. All it took was one e-mail to Larry."

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