It is under a patent rule called the doctrine of equivalents.

FORBES: Me-too patents

Simply make the basic rule about costs in patent cases loser pays.

FORBES: The Shield Act Tries To Kill The Patent Trolls. But Does It Go Far Enough?

The patent reform bill -- we obviously support the repeal of the 3 percent withholding rule, which, by the way, was passed in 2006, signed into law by President Bush, and was voted for by Representatives Boehner and Cantor.

WHITEHOUSE: The White House

These NPEs must uncover evidence of infringement, rule out prior art and inequitable conduct, and interact at length with the patent office.

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