Microsoft is on the move.  I believe Microsoft simply purchased product from these companies and then tested the software for authenticity.

Read Microsoft's press release.  Excerpt: "As part of Microsoft Corp.’s commitment to honest business partners that distribute the company’s products, the company announced 20 lawsuits today against resellers allegedly engaged in the distribution of infringing software and software components. The company also announced research findings from its first large-scale forensic analysis of counterfeit versions of Microsoft® Windows® XP acquired in 17 countries around the world, which it says demonstrates that counterfeit software contains risks for typical users, not just the “pirates” who manufacture and sell it."