These patent owners do not use (i.e. licence or assign) or manufacture on the basis of their patents or patent portfolio. Many instead see patent ownership as a means of hijacking another’s success in their field, with minimal effort or expense. (...)
These parties have no manufacturing or research base, no intention to use the patents, and only seek to enforce their Intellectual Property Rights once another company or individual has independently come to the technology, and have committed themselves to the enterprise.
Of course, everything in these lines describing a "troll" applies to the University of Rochester in its unsuccessful infringement suit against Searle.
Missing the point on Bayh-Dole