Not sure it is right to call Bridge Crossing LLC a patent troll. A significant portion of the funding for this came from ARM. The same was true for the Nortel patents acquired by Apple and Microsoft. Are they suddenly trolls?
British company Imagination bought MIPS engineers for 300k$ per each one, plus 80+ core MIPS patents. The remaining 500 patents were sold for 350M$ to another company that's pure IP aka patent trolls. http://www.zdnet.com/chip-designer-mips-acquired-for-60m-patents-sold-for-350m-7000006969/