SANTA MONICA, Calif., Jan. 23 -- Stamps.com(TM) announced today that it has filed a patent counterclaim against Pitney Bowes alleging that Pitney Bowes' DM Series Mailing Systems infringe three Stamps.com patents. The DM Series, a line of digital metering products introduced by Pitney Bowes in April 2002, has been described by Pitney Bowes as "the most extensive and technologically advanced line of solutions they have introduced in their 82 year history." In addition to seeking damages for Pitney Bowes' infringement, Stamps.com's counterclaim in the United States District Court in Delaware seeks a permanent injunction that would prohibit Pitney Bowes from making, using and selling infringing DM Series products. Stamps.com also answered Pitney Bowes' latest complaint by denying Pitney Bowes' allegations that its NetStamps(TM) product infringes Pitney Bowes' patents. In a separate suit that is expected to go to trial this year, Stamps.com seeks additional damages and a permanent injunction based on Pitney Bowes' infringement of three other Stamps.com patents. "We look forward to vindicating our rights at trial this year and obtaining damages and injunctive relief. The counterclaim filed today will help further establish that Pitney Bowes' DM Series mailers are based on Stamps.com's patents," said Seth Weisberg, Vice President and General Counsel of Stamps.com. Stamps.com is committed to strategically managing and licensing its intellectual property portfolio to enhance shareholder value. Stamps.com has over 50 issued patents and 80 patent applications worldwide specifically related to computer-generated postage and digital metering technology.