Microsoft had argued that the transfer of Dr Kai-Fu Lee from Microsoft to Google China violated the company's confidentiality and non-competitive agreements. Lee held a position as head of research and development at both companies' China offices.
Google disclosed that it had hired Lee on 19 July, and insisted that he would not be doing anything that would conflict with the work he did at Microsoft.
But Microsoft stated in its legal complaint that Lee had played a key role in its China operations and had worked on search technology.
The restraining order issued by Judge Steven Gonzales prevents Lee from working on search technology, business strategy, planning or development or any other area in which he worked while at Microsoft.
The next hearing in the case is scheduled for September.
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