TROY — Was the technology that powers the iPhone's popular Siri voice-recognition application invented at Rensselaer Polytechnic Institute in Troy?

That will have to be decided in federal court after a Texas company that holds the license for a similar invention developed at RPI more than a decade ago is suing Apple for patent infringement.

Long before Apple Inc. revolutionized the smartphone with the release of the first iPhone in 2007, RPI professor Cheng Hsu and his doctoral student, Veera Boonjing, invented a "natural language interface" system that can answer questions posed by human speech by doing sophisticated database searches.

Hsu and Boonjing filed for a U.S. patent to protect the invention back in 2000. RPI, which owns intellectual property developed by its researchers, subsequently sold an exclusive license for the patent to a Dallas company called Dynamic Advances LLC.

In a lawsuit filed Friday in U.S. District Court in Albany, Dynamic Advances says that Siri was built using some of the technology covered by that patent, which was granted in 2007. Dynamic Advances is seeking unspecified damages in the case — although the lawsuit does say that it is owed "in no event less than a reasonable royalty."

Apple has been the target of many lawsuits over Siri, which first appeared on the iPhone 4S, which was released a year ago this month to both acclaim and disdain. Some of the lawsuits have been filed by consumers who say Siri did not live up to the company's hype, while other inventors have sued arguing they had also created the technology.

Apple did not immediately respond to requests for comment on the Dynamic Advances lawsuit. James Muldoon, a Syracuse-based attorney with Harris Beach PLLC who is representing the Texas company in the case, was out of the office Monday and not immediately available to talk. RPI is not a plaintiff.

Neither is Hsu, the RPI professor who invented the technology along with Boonjing.

Hsu, who has worked at RPI since the 1980s, is a professor of industrial and systems engineering as well as information technology. Boonjing, also not a plaintiff, is now a mathematics and computer science professor in Thailand.

In a brief interview Monday as he was about to teach a class, Hsu said that he and Boonjing worked for years on their natural language interface invention as part of the larger quest in the academic community to enable the use of artificial intelligence.

However, at the time, there wasn't a definitive commercial application since smartphones had yet to be developed into the hand-held do-it-all devices that they are today.

"It was ahead of its time at that point," Hsu said. "Who would have thought that that kind of market would be created?"

Hsu says he doesn't know much about Dynamic Advances except that it specializes in intellectual property. It is unclear how much the license from RPI cost.

Hsu says he's used Siri, and it has features that are covered by the RPI patent.

"From our perspective, I guess I'd say 'Sorry, we got there first,'" he said.

lrulison@timesunion.com • 518-454-5504 • @larryrulison