Apple is attempting to protect its products that use 3G and 4G powered by a Qualcomm baseband chip.
Qualcomm and Motorola already have a patent license agreement. Apple needs to enforce its rights as a third-party beneficiary of this agreement, or its products that feature the Qualcomm baseband chip (the iPhone 4S, the 4G iPad, and presumably the new iPhone, could be at risk.
In order to protect its iDevices Apple has made a third attempt at bringing a patent-exhaustion-based "antisuit" lawsuit against Google subsidiary Motorola Mobility, reports FossPatents. Motorola wants this California lawsuit dismissed.
Apple has already been asked to remove some 3G-compatible products from its online store in Germany. Apple and Motorola are currently undergoing a related antitrust lawsuit in Germany.
Apple claims it is willing to take a FRAND license to Motorola’s standard essential patents.
At issue is Motorola's "termination" of its license agreement with Qualcomm with respect to Apple as a third-party beneficiary.
Foss Patents has lots more information.