Rovio, the Finnish game company responsible for the runaway hit Angry Birds, is currently facing a legal issue on patent violation. Angry Birds is maintaining popularity at one million downloads per day, garnering the attention of patent warriors across the land.  Rovio is being sued by U.S Texas-based firm Lodsys for patent violations, which covers the methods for purchasing new levels inside the Angry Birds game.

This particular in-app payment feature has caused the prevention of other European game developers to launch their apps in the US, posing a major threat in the ongoing development of mobile app ecosystem.

“The US patent system allows software implementations of ideas to be patented, which differs significantly from the European Union, although the European Parliament has been considering aligning patent rights with the US,” according to Start up Smart, a website for new businesses and entrepreneurs.

Patent infringement is a common control tactic nowadays, particularly in the mobile industry.  The mobile ecosystem as a whole is under siege, with handset and software makers battling for their rightful piece of the pie.  The most recent case was between Apple and HTC’s mobile patent issue, with HTC seeking a deal with Apple. In addition, Apple has also filed a patent lawsuit against Android smartphone makers Samsung and Motorola, while Microsoft is suing Motorola for patent infringement as well.

With all of the increasing patent lawsuits, to be able to survive the competition, game companies such as Rovio aim to boost their animation production capabilities.  Just last month Rovio took another step in advancing their stance and improve mobile gaming with the acquisition of Helsinki, Finland-based animation studio Kombo.