I don't think that the companies referred to in the Huffington article developed technology that had come to market and had been sold in retail products by the designing firm, had been shown to the infringer, had been made a substantial offer by the infringer, and then saw the infringer bring the technology to market themselves without paying the patent owner. That does not fit the definition of a patent troll.
That said, even patent trolls sometimes win in court and make lots of money as a result.
QC then patented PV's art without citing PV. They have a better damage theory too or, more precisely, one that can either replace or compliment other lesser ones, like the offer. Makes invalidity arguments a little ... say ... awkward too, wouldn't you say?
One of the best patent troll stories was the interesting case of SCO, previously a well respected purveyor of Unix, who decided they held patents on Linux and started sueing left and right. Did not end well for them.