The International Trade Commission said on Tuesday that it would investigate allegations by Prism Technologies that BlackBerry maker Research in Motion violated one of its patents.

Prism Technologies, whose one-page website says it does Internet Security Technology Management and Licensing, accused RIM of violating a patent having to do with authentication systems.

Edward Snyder, an analyst with Charter Equity Research, said RIM's share price did not move on announcement of the Prism lawsuit because investors worry about patent suits only if the company is short on cash.

The probability of (Prism) prevailing are relatively slim. And even if it does, the likely impact to the stock is minor, he said. I've not heard of them (Prism) before, they're not going to be somebody who is pre-eminent in tech.

A representative of RIM could not immediately be reached for comment.

The maker of the popular BlackBerry smartphone has had several legal battles over patents in recent years.

In July, RIM settled a long-running patent dispute with tiny tech company Visto Corp, agreeing to pay Visto $267.5 million to settle all outstanding litigation over technology.

And in 2006 it agreed to pay more than $600 million to NTP to settle a damaging and drawn-out patent infringement fight.

(Reporting by Diane Bartz; additional reporting by Jeffrey Hodgson and Alexei Oreskovic, editing by Matthew Lewis)