I've bought all three (CND, CCO and Blue Sky) because this post was bugging me, so, I thought I would do a test. I think that the Blue Sky one isn't quite as 'brilliant' as CND and CCO. I bought all three in the same colour just to check and bought all the base coats and top coats and I drew a hand on a piece of paper and wrote out which finger was which) and wore the same colour on each nail. The colour was Iced Cappucino. On the back of the CCO brand, it has a patent pending in China mark SKU 40401 P/N 77521. When I do a search for Creative Nail Design, there is a patent there, but, doesn't seem to be for 'shellac' (I don't think I can post the link, but, this is the patent number: US 8,124,058 B2 and it reads " A method for reducing or eliminating delamination of an artificial nail structure from a natural nail surface, wherein said artificial nail structure is obtained by polymerizing on the natural nail surface a polymerizable monomer composition, said method comprising adding to said polymerizable monomer composition an effective amount of at least one multicarbonyl-vinyl containing monomer and at least one other ethylenically unsaturated monomer." (This is an awarded patent). However, it doesn't seem to have anything to do with their Shellac and I think I read that CND shellac is also 'patent pending' (which would mean that the patent has not yet been approved by the USPTO. Just looked it up out of curiosity because you all seem to have been debating this for a while. In my search, the only patent pending I could find was the one in China. The word 'shellac' is actually 'registered' by CND though. (but, that is only one-word, for example, CCO could apply for 'CCO shellac' in the USA and be awarded the 'registration' quite easily.
I think that China is probably the supplier of the CND shellac based on what I've researched and you all can check it out as well, you have the information now.. (personal thoughts)