Well the truth is only some of them have to answer to that patent infringement suit by DGTLF.
DGTLF's patent only applies to 3-piece electronic cigarettes with external atomizers. There is another patent out there owned by a company called Loongtotem on the 2-piece (Cartomizer) electronic cigarette - which should bypass any infringement suit from DGTLF.
Which is probably why blucigs switched over to cartomizers as soon as the got news on the lawsuit.