Laurent Chavet, 29, of Kirkland, Washington, worked for search company Alta Vista for around two and a half years before leaving the company in February 2002.
In March 2002, according to the indictment, Chavet unlawfully accessed Alta Vista's system to obtain source code belonging to the search engine. The indictment also alleges that Chavet unlawfully accessed Alta Vista's computer system again in June 2002 and, in doing so, caused damage in excess of $5,000 to that computer system.
Microsoft did not employ Chavet at the time of the alleged offences, but Tami Begasse, a spokeswoman for Microsoft, confirmed to Associated Press that he is employed by the company now.
Begasse added, "We're confident in our policies and procedures we have in place to protect our code and to ensure that employees do not bring third party code into the work place."
Chavet faces a maximum sentence of five years imprisonment and a fine of $250,000 for each indictment.