Motorola, just days after being targeted in a patent suit by Microsoft, filed complaints against Apple on Wednesday alleging that the iPhone, iPad and other products infringe its patents.

Motorola's subsidiary, Motorola Mobility, Inc., has filed a complaint with the U.S. International Trade Commission (ITC) alleging that Apple?s iPhone, iPad, iTouch and certain Mac computers infringe Motorola patents. Motorola Mobility also filed patent infringement complaints against Apple in the Northern District of Illinois and the Southern District of Florida.

Overall, Motorola Mobility?s three complaints include 18 patents, which relate to early-stage innovations developed by Motorola in key technology areas found on many of Apple?s core products and associated services, including MobileMe and the App Store. The Motorola patents include wireless communication technologies, such as WCDMA (3G), GPRS, 802.11 and antenna design, and key smartphone technologies including wireless email, proximity sensing, software application management, location-based services and multi-device synchronization.

Motorola Mobility has requested that the ITC commence an investigation into Apple?s use of Motorola?s patents and, among other things, issue an Exclusion Order barring Apple?s importation of infringing products, prohibiting further sales of infringing products that have already been imported, and halting the marketing, advertising, demonstration and warehousing of inventory for distribution and use of such imported products in the United States. In the District Court actions, Motorola Mobility has requested that Apple cease using Motorola?s patented technology and provide compensation for Apple?s past infringement.

Kirk Dailey, corporate vice president of intellectual property at Motorola Mobility, said, "Motorola has innovated and patented throughout every cycle of the telecommunications industry evolution, from Motorola?s invention of the cell phone to its development of premier smartphone products. We have extensively licensed our industry-leading intellectual property portfolio, consisting of tens of thousands of patents in the U.S. and worldwide. After Apple?s late entry into the telecommunications market, we engaged in lengthy negotiations, but Apple has refused to take a license. We had no choice but to file these complaints to halt Apple?s continued infringement. Motorola will continue to take all necessary steps to protect its R&D and intellectual property, which are critical to the company?s business."

Patent lawsuits are a regular occurrence among technology giants and Motorola's complaints against Apple come just days after US software giant Microsoft filed suit against Motorola.

Microsoft on Friday accused Motorola of violating its patents in mobile phones powered by Google's Android operating system.

Apple is currently being sued by Finnish mobile phone giant Nokia for patent infringement and has fired back with a countersuit against Nokia.