While I am unsure on the matter, I think nChain has the largest portfolio of patents in the crypto currency and Blockchain space. Not knowing your definition of "patent troll" -- not exactly a dictionary term -- I really have no way to respond to your question.
A patent troll uses patents as legal weapons, instead of actually creating any new products or coming up with new ideas. Instead, trolls are in the business of litigation (or even just threatening litigation). They often buy up patents cheaply from companies down on their luck who are looking to monetize what resources they have left, such as patents. Unfortunately, the Patent Office has a habit of issuing patents for ideas that are neither new nor revolutionary, and these patents can be very broad, covering everyday or commonsense types of computing things that should never have been patented in the first place.
Source:
https://www.eff.org/issues/resources-patent-troll-victimsPatent trolls generally patent things that are very general and the intent is to earn from the patent rather than from the innovation.
The patents are designed to hinder innovation by others or to earn money from the efforts of others by demanding a "license fee" for "using their very broad and generic patent".
The patents themselves are usually not unique and cover a general idea rather than create innovation.
e.g. Providing WIFI in a business to the public.
https://www.eff.org/deeplinks/2014/02/infamous-wi-fi-patent-troll-settles-peanutsOr the patents cover something that is already in the public domain or something someone else invented but did not patent.