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I might go with that but for the fact that Microsoft wrote the first of the "Halloween" documents in 1998

From Wikipedia:

"The first Halloween document, requested by senior vice-president James Allchin for the attention of senior vice-president Paul Maritz and written by Microsoft program manager Vinod Valloppillil, was leaked to Eric Raymond in October 1998, who immediately published an annotated version on his web site. The document contained references to a second memorandum specifically dealing with Linux, and that document, authored by Vinod Valloppillil and Josh Cohen at Microsoft, was also obtained, annotated and published by Raymond. Microsoft has since admitted the documents' authenticity.

Marked "Microsoft confidential", they identify open-source software, and in particular the Linux operating system, as a major threat to Microsoft's dominance of the software industry, and suggest ways in which Microsoft could disrupt the progress of open source software.

These documents acknowledged that free software products such as Linux were technologically competitive with some of Microsoft's products, and set out a strategy to combat them. The documents were embarrassing largely because they contradicted Microsoft's public pronouncements on the subject."

http://en.wikipedia.org/wiki/Halloween_Documents

It's a well known fact that before 2000 MS was seriously worried about Linux.