Google's browser toolbar is back in court on patent infringement charges, after a US court of appeals overturned part of a lower court decision. Google's AdSense contextual advertising service, though, is in the clear.
Hyperphrase Technologies filed suit against Google in April 2006, alleging that Google's AdSense and the AutoLink function of its toolbar infringed claims in four Hyperphrase patents relating to the contextual linking and presentation of information. The US District Court for the Western District of Wisconsin rejected the allegations in a summary judgement in Google's favour, and Hyperphrase appealed.
On Wednesday, the US Court of Appeals for the Federal Circuit upheld the parts of the summary judgement relating to AdSense, and some of the claims against AutoLink, but overturned the part of the ruling dealing with AutoLink's alleged infringement of two of the patents. It remanded the case to the district court to be reexamined.
AutoLink parses Web pages for text fragments in certain formats, and transforms them into links to Web pages it deems appropriate. For instance, it will link publication International Standard Book Numbers (ISBNs) to a corresponding listing on Amazon.com's bookstore, or link package tracking numbers to pages showing delivery status. It will similarly process US street addresses and US vehicle identification numbers.
In its ruling, the court of appeals found that the district court had considered an inappropriate interpretation for "data reference," one of the terms used in the patent claims to describe the way a link is made between a fragment of text and an element in a database. The court of appeals remanded the case to the district court to determine whether AutoLink infringed the patents under the new interpretation it suggested.