Drug firms have been known to file patents that really shouldn't hold up in court -- extending the patent lives of their drugs well beyond any reasonable term.

FORBES

The appeals court held that the agency had misinterpreted both the law governing patent term length and a clause barring the double-counting of overlapping prosecution delays.

FORBES: Novartis Challenges USPTO Patent Extension Policy

But while Cannata and patent investors like Rembrandt claim to be protecting the rights of inventors, their detractors believe they are simply well-financed patent trolls--a derisive term used to describe companies with no operations other than suing big business over patents.

FORBES: Patent Payday