By Chris Smith

Published: 06:15 PM EST (03:15 PM PST)

HTC this week used nine patents recently obtained from Google to up the ante in its high-stakes intellectual properly infringement war with Apple, slapping the iPhone maker with a third lawsuit while amending a previous complaint to allege broader infringement.

According to Bloomberg’s assessment of U.S. Patent and Trademark Office records, the nine patents that were transferred to HTC on Sept. 1 originated from Palm, Motorola and Openwave, with Google taking ownership of them over the course of the past year.

In a formal complaint filed Wednesday in a Delaware federal court, HTC alleged new infringement by Apple on four of the patents that were first issued to Motorola.

Separately, HTC also amended a complaint with the U.S. International Trade Commission, originally filed against Apple in May, by alleging the Cupertino, Calif.-based company is in violation of the remaining five newly acquired patents, two of them previously owned by Palm and three others initially issued to Openwave.

HTC countersued Apple in May after the iPhone maker accused HTC of infringing on 20 patents related to the iPhone with its own touch-screen devices. The Taiwanese company then sued Apple again in mid-August, claiming that products such as the Mac, iPhone and iPad infringe on three HTC patents.

The U.S. International Trade Commission has also agreed to investigate a second Apple patent infringement suit against HTC that was filed in July, a week before a judge ruled that HTC is in violation of two patents asserted by Apple in the initial trial.

Those two patents, U.S. Patent Nos. 5,946,647 and 6,343,263, are still subject to review by the full commission. Apple has specifically highlighted the second filing in recent proceedings, implying that Google’s Andy Rubin may have gotten inspiration for a related component of Android while working at Apple in the early 1990s.

Apple has yet to file a formal complaint against Google regarding the patent, but does have an ongoing infringement case pending against Motorola Mobility on the matter. The patent could therefore pose issues for Google down the line should the search giant's proposed acquisition of Motorola Mobility gain approval.

For its part, Google hasn't initiated a formal complaint against Apple either but it did take a public position in March in which it stated that it intends to “stand behind [its] Android operating system and the partners who have helped [it] to develop it,” without actually detailing any plans to officially oppose Apple’s legal claims in court.