A Motorola Mobility patent that was successfully used to force Apple to turn off its iCloud services in Germany last year could be invalid, the District Court in Mannheim, Germany, says, as reported "PC World: (http://tinyurl.com/c485tmv).

The court said it doubted the validity of Motorola's patent entitled "Multiple Pager Status Synchronization System and Method," also known as the push notification patent, in a lawsuit between Motorola and Microsoft. Google-owned Motorola alleged that several Windows Phone devices in Germany infringed on this patent. The court, however, decided to postpone a decision in the case pending a validity procedure about the patent in the German Federal Patent Court.

This is part of an ongoing battle. Apple has alleged that Motorola infringes 24 of its patents (21 of them with Android-based phones, the remaining three with set-top boxes and DVRs), while Motorola previously asserted 18 patents against a variety of Apple products (mostly but not exclusively iPhone, iPad and iPod). Litigation between the two companies has taken place in several different federal courts.