The U.S. Patent and Trademark Office has given another boost to eBay Inc. in its legal fight with MercExchange Inc. by signaling that it may revoke a second patent owned by the small Virginia business.
In a filing posted on its Web site, the patent office said it found the latest patent to be invalid because its claimed inventions either were obvious or had been anticipated by other patents.
The decision could prove very helpful in eBay's attempt to challenge a $25 million patent infringement award won by MercExchange in 2003.
The patent office made a similar ruling in January involving another MercExchange patent. In both cases, the decisions by the patent office are preliminary, and any final rulings can be appealed inside the patent office as well as through the federal court system.
MercExchange said it plans to appeal.
"We will deal with this office action, like all previous office actions during the prosecution of our patents, in the ordinary course," said Thomas G. Woolston, a patent attorney who owns MercExchange.