On Friday, Xerox PARC is announcing that it is licensing a broad portfolio of patents and technology to a well-financed start-up with an ambitious and potentially lucrative goal: to build a search engine that could some day rival Google.

The start-up, Powerset, is licensing PARC’s “natural language” technology. Powerset hopes the technology will be the basis of a new search engine that allows users to type queries in plain English, rather than using keywords.

As part of the deal, a leading natural-language researcher at PARC, Ronald M. Kaplan, will join Powerset’s staff of about 40 as chief technology and scientific officer.