Patent attorneys who followed a controversial patent blog to keep up with IP issues may lose the resource now that the anonymous blogger unmasked himself this weekend.

Facing an e-mailed threat of being named, Richard Frenkel, a director in Cisco Systems’ intellectual property group, identified himself on Saturday as the author of Patent Troll Tracker, a blog that reports on companies that critics, including Frenkel, argue hold patents solely to sue for infringement.