
US investigations have targeted one Pennsylvanian trader suspected of running 20 websites peddling fake Adobe, Microsoft, McAfee and Symantec software.
The UK defendant, who cannot be named for legal reasons, is charged with selling copies of Autodesk's design software on the web.
In Germany, three websites were found offering Adobe products and two preliminary injunctions have been issued, with the owners' property being searched for evidence.
The third German seller was found to have headquarters in Austria, where a complaint has since been filed.
"To all offenders out there, large or small, our message remains the same," said John Wolfe, director of internet enforcement at the BSA.
"Software piracy is illegal and we will be bringing legal actions against internet pirates to tackle this serious problem."
Wolfe said that today's international actions marked the beginning of the BSA's expanded efforts to fight global software piracy.
The BSA said that in all five of cases it had been alerted to the illegal activity by reports and complaints from consumers who had been duped by low-price deals.
During 2006, the BSA shut down online auctions offering more than 20,000 software products with a total value of more than US$17 million.
It also filed notices for over two million non-auction copies of software with a total value of more than US$12million.
In the US the BSA shut down 8,025 auction sites in 2006, as well as closing 5,961 sites internationally.