A software data analysis firm disputed the validity of, although documents show the company may be incorrect in its conclusions.
Tyron Stading, founder and chief technology officer of Innography, a software company that pores through data related to intellectual property, said his company's analysis found that Google may not have had the right to sell two of the nine patents.
At issue were missing signatures from the original inventors of patents bought from Palm and Motorola. In both cases, inventors didn't assign the technology to the company, meaning they weren't in the position to sell the patents, according to Stading. He added that in past instances where this has happened, the court has thrown out a case if the plaintiff isn't able to prove proper ownership of the patents.
But documents reviewed by CNET showed a clear transfer of ownership in both cases.
HTC, meanwhile, stood by the strength of its patents.
"HTC is confident in its ownership of the patents and its right to use the patents in its lawsuits against Apple," a company representative told CNET.
HTC is counting on these patents in its legal counterattack against Apple. Last week, the company filed a new lawsuit in the federal district court in Delaware and amended its complaint with the International Trade Commission to incorporate the new intellectual property.
For Google, it represented the first direct support of one of its Android partners. Several companies, including HTC, Samsung Electronics, and Motorola Mobility, had been targets of lawsuits by Apple. In response,and its 17,000 patents (with 7,500 pending).
Stading said that all of the parties have been notified of the ownership issues with the two patents. He said he wouldn't disclose if Innography was working with either side.
Innography, however, may have been looking at patents listed on the Patent and Trademark Office Web site, and not a more complete version available in the public record. More complete copies of the Motorola and Palm patents show the necessary signatures.
Looking at the ownership status of patents is an increasingly popular legal tactic, Stading said. He added that he has seen a dozen instances this year where a case has been thrown out over the issue.
Updated at 6:50 p.m. PT: Changed the headline and introductory paragraph, and added details on the disputed patents to reflect proper transfer of ownership from Google to HTC.
Updated at 5:58 p.m. PT: to include a comment from HTC and a review of one of the patents.