It's up to patent holders to file documents showing transfer of ownership with the patent office, so the discrepancy of timing probably means only that the company was slow in doing its paperwork, said David Mixon, a patent attorney with Bradley Arant Boult Cummings LLP.

While patent lawsuits have become commonplace in the mobile industry, this one has a unique twist. Google, which recently announced plans to acquire Motorola, is an investor in Intellectual Ventures, patent expert Florian Mueller .

That doesn't make Google fully responsible for the suit against Motorola. Intellectual Ventures operates like a group of companies, and Google did not invest in the arm that filed the lawsuit, Mueller wrote. However, Google's investment lent legitimacy to a company whose lawsuit now targets Android, a Google creation. Mueller concluded that, as an investor, "Google played a key role in turning IV into what it is and it should never give money to... any company setting up patent funds without taking care of the Android ecosystem at large."

The IDG News Service