Question:

Lets say a potential candidate works for Company "ABC" as a contractor thru a vendor and has employer "John Doe".
Now for 2021 Cap, Company ABC offered full time job to the candidate and agreed to Sponsor H1B for the cap as future employment.
Meanwhile the employer "John Doe" is also filing H1B saying the candidate is already working for him and at Client location "ABC" Company.

Will this be considered as duplicate filing ? Please provide your inputs.
Thank you