MFSL Not stamped

I have been regularly purchasing mfsl vinyl from a reputable shop in Northern California. None of the records have any stamped number in the box that is usually earmarked for the numbered edition of record..the box is there but is blank. What does it all mean? Are they test pressings? More valuable?
Probably a promotional copy. What title is it?
Beck/Sea Change,Basement Tapes,Dave Alvin,Marvin Gaye/Whats goin on,Isaac Hayes/Hot Buttered Soul....the list goes on...all unnumbered.
I'm pretty sure these are promo copies.