Google announced today that it has added European patents to go along with its U.S. patents in its patent search tool.

In addition to adding millions of patents, Google has added a feature called the Prior Art Finder.

“Typically, patents are granted only if an invention is new and not obvious,” explains engineering manager Jon Orwant. “To explain why an invention is new, inventors will usually cite prior art such as earlier patent applications or journal articles. Determining the novelty of a patent can be difficult, requiring a laborious search through many sources, and so we’ve built a Prior Art Finder to make this process easier. With a single click, it searches multiple sources for related content that existed at the time the patent was filed.”

The Prior Art Finder, Google says, identifies key phrases, combines them into a search query, and displays relevant results from Google Patents, as well as Google Scholar, Google Books, and the web. A button for the feature will appear on individual patent pages.

“Our hope is that this tool will give patent searchers another way to discover information relevant to a patent application, supplementing the search techniques they use today,” says Orwant. “We’ll be refining and extending the Prior Art Finder as we develop a better understanding of how to analyze patent claims and how to integrate the results into the workflow of patent searchers.”

Google, meanwhile, has also been adding to its data from the U.S. Patent Office, and without getting specific, the company promises that more related stuff is on the way.