H1B (CP) never activated. Will it be cap exempted.

[raviead]

I am working on L1, I got h1b in counselor processing from company i am working in (Say A) this year.
After Oct 1st, can i join company B using H1B even though i have never worked on H1B/Got visa stamped in company A.

i.e. Do i have to work on H1B atleast 1 pay cheque in company A before i can transfer to company B as cap exempt?

I assume i don't have to. But there are conflicting articles online, it's confusing.

Any help is highly appreciated.