NF, without pictures, would make me think about "Norme Francaise" , something the french were stamping on any product to be certified.
Superia had a similar "bad" design of the seat post lug and had nothing to do with Cinelli.
I write bad because it was well known by the competitors that this design was not strong enough to clamp correctly the saddle post.

Van Looy was know for his Galmozzi.
Merck, however...

Noel ran also for Superia.

Pictures?