Anticipating a patent infringement lawsuit from Netlist, a maker of high-density memory subsystems, Google has taken the offensive and filed for a declaratory judgment to invalidate the patent in question.

The patent, Memory module decoder (U.S. Patent No. 7,289,386), describes a memory module and printed circuit board with a coupled logic element. It was issued to Netlist last October.

Having been sued six times already this year for patent infringement, Google has decided to launch pre-emptive litigation rather than waiting around to be served with patent lawsuit No. 7.

In 2006, according to Google's legal filing, Google considered business proposals from Netlist to supply it with server memory hardware for some of its servers. It ended up buying from a different supplier.

In May 2008, Netlist's CEO and president, Chun Hong, wrote to Google and claimed that the memory modules Google had chosen infringed Netlist's patent.

Netlist's outside counsel, Morrison & Foerster, sent two follow-up letters in June.

Google, believing that litigation was imminent, responded by asking the court to issue a declaratory judgment that it is not infringing Netlist's patent and that Netlist's patent isn't valid.

Google's court filing says the Netlist patent is invalid because it fails to comply with various conditions and requirements set forth in patent law.

A Netlist spokesperson did not answer calls seeking comment.

Google did not respond to a request for comment.

Google, a prolific filer of patents, has been vocal in its support for patent reform. "Unfortunately, the patent system has not kept pace with the changes in the innovation economy," said Google policy counsel and legislative strategist Johanna Shelton and Michelle Lee, head of patents and patent strategy, in a blog post last September. "Google and other technology companies increasingly face mounting legal costs to defend against frivolous patent claims from parties gaming the system to forestall competition or reap windfall profits."

"Patent Trolls plague the IT industry. They hold innovation hostage by exploiting our antiquated patent system to thwart IT development," the Computing Technology Association, an IT business group, said earlier this month.

Defenders of the U.S. patent system reject the pejorative term "patent troll" and argue that big companies need to be held accountable when they infringe an inventor's patents.

Earlier this year, the Patent Reform Act stalled in Congress. The proposed legislation is unlikely to be revisited until after the presidential election.