Proper uses of a means plus function limitation

Posted On :April 9th, 2012 By James Yang

The following case illustrates my propensity for limiting my use of what patent attorneys call the means plus function claim limitation.  There are particular uses for means plus function limitations but more often than not, they seem to be more trouble than they are worth.  I will go over some instances where I think that [...]

Reducing Scope of Doctrine of Equivalents Via Ensnarement Defense

Posted On :June 26th, 2009 By James Yang

As previously discussed in “Avoiding Patent Infringement,” the claims define the metes and bounds of patent protection afforded under a patent.  The claims can be infringed either literally which means that the alleged infringer practiced the claimed invention without any deviation.  If the alleged infringer practiced a variation of the claimed invention, then liability for [...]

Doctrine of Equivalents – BINGO

Posted On :August 7th, 2007 By James Yang

In Planet Bingo LLC v. GameTech International Inc., 81 USPQ2d 1145 (Fed. Cir. 2006), the Federal Circuit upheld the District Court’s decision of non-infringement under the Doctrine of Equivalents because determining a winning combination after a first ball in a bingo game is drawn is substantially different from determining a winning combination before drawing the [...]