Nuance Communications this week filed suit in a U.S. district court in Texas against vlingo, claiming that the company infringes on a Nuance patent (Number 6,766,295) that covers a technique for adapting a speech recognition system to specific users or groups. In the claim, Nuance seeks monetary damages and an injunction to prevent vlingo from using the technology.

The patent, one of more than a 1,000 patents and patent applications that Nuance holds in the fields of speech and imaging technologies, applies to "Adaptation of a Speech Recognition System across Multiple Remote Sessions with a Speaker."

In an official statement, vlingo CEO Dave Grannan called Nuance’s claims "unfounded," adding that the patent in question "does not apply to vlingo-developed technology nor the third-party licenses we employ."

Vlingo asserts that its adaptive technologies employ speech recognition based on a Hierarchical Language Model (HLM) with a very large vocabulary that includes millions of words. These HLMs can predict what words users are likely to say and how words are grouped together and take into account what users have spoken in the particular text box in the particular application, and therefore improve with usage. In addition to adapting the HLMs, the system adapts to many user and application attributes, learning the speech patterns of individuals and groups of users, new words, and pronunciations of words based on usage. It can, over time, recognize that a particular user tends to ask for Mexican food. Furthermore, a first-time user with a Southern accent benefits from other users who have spoken into the system with a Southern accent.

Grannan questions the validity of the Nuance patent and said his company "intends to fight the lawsuit aggressively to its conclusion."

Still, Nuance apparently has no plans of backing down. In an official statement of its own, Nuance vice president and general counsel Jo-Anne Sinclair said her company "has invested significant resources in developing technologies, building solutions, and acquiring intellectual property. These inventions and the intellectual property protecting those inventions are a cornerstone of our business. We take great pride in and place significant value on our patents and will aggressively protect our intellectual property rights through all available means."