This story from law.com:

"A rare U.S. Court of Appeals for the Federal Circuit decision that declared a patent unenforceable because of the patent attorney’s inequitable conduct during the patent application process is likely to increase lawyers’ disclosures to the patent office.

On May 18, the court upheld a California federal court decision that declared a McKesson Information Solutions August 1989 patent involving bar-coding technology for hospitals unenforceable.

The Federal Circuit agreed with the lower court that patent lawyer Michael Schumann acted with deceptive intent by withholding three key items of information from the U.S. Patent and Trademark Office, including details about prior art and a rejected co-pending patent application.

Schumann, who is now with Minneapolis-based intellectual property firm Hamre, Schumann, Mueller & Larson, declined to comment. "