Microsoft said Wednesday that it has filed lawsuits against eight sellers of what the software firm said were counterfeit copies of its software. Microsoft said the sellers all used eBay for their transactions.

Most were accused of selling versions of Windows XP, but the alleged bootleg software in question also included versions of Office 2002 and 2003. The complaints were filed in U.S. Federal District Courts across the country from Massachusetts to Hawaii.

"We strongly believe in the convenience and global reach of the virtual marketplace," said Matt Lundy, a Microsoft attorney, in a statement. "Unfortunately, a number of online sellers are undermining trust in the system by using the Internet to hawk illegal products to unsuspecting consumers."

The defendants listed by Microsoft are: Igor Goldshteyn, case filed in District of Arizona court; John Hilaire, District of Connecticut; Jaike Hornreich, Southern District of Florida; Billy Williams, District of Hawaii; Edward Shklovsky, District of Massachusetts; Jay D. Smith, District of Nebraska; Great Product Deals Inc., Western District of New York; and Agus Chandra, Western District of Washington.

None of the defendants could be immediately located for comment. As for eBay, a spokesman said the online auction firm has a "firm policy" aimed at stopping the sale of counterfeit goods.

Spokesman Hani Durzy said eBay's Verified Rights Owner Program (VeRO) enables owners of goods sold on eBay to report violations. He noted that Microsoft has participated in the program for years and he indicated that eBay would act against the eight defendants cited by Microsoft Wednesday.

"Selling counterfeit goods is illegal," he said, noting that more than 14,000 parties have participated in the VeRO program. "We come down firmly on this. VeRO is incredibly effective."

Microsoft said it caught seven of the defendants when their customers used Microsoft's online software validation tool, Windows Genuine Advantage (WGA) Program. WGA offers users the opportunity to report counterfeit reports when they don't receive approved Microsoft software.

In announcing the filing of the eight cases, Microsoft noted that the Business Software Alliance, a trade association, has reported that 21 percent of software in the U.S. is pirated.