Worlds.com was undoubtedly one of the pioneers in the virtual worlds space, but it's since been overtaken by the likes of Second Life, Habbo, Club Penguin and numerous others.

However, the company is fighting back, claiming its patent for scalable virtual worlds with thousands of users is being infringed by rivals - and that it's prepared to sue.

The company is suing Korean MMO publisher NCSoft, and Worlds.com CEO Thom Kidrin tells Silicon Alley Insiderthat if successful, the company will go after Second Life and World of Warcraft next.

The patent covers "a highly scalable architecture for a three dimensional, multi-user, interactive virtual world system" according to Worlds.com's announcement when it was granted last year.

It was apparently based on work for a virtual world called Starbright World back in 1997, with Worlds.com having since acquired those patents.

The affair could have major implications for mobile games companies, particularly if Worlds.com does focus its attentions on the MMO space.