B.J. Interruptus -- 'Deep Throat' Owner Sues to Block 'Lovelace'

The production company that owns the legendary, XXX movie, "Deep Throat" is suing the producers of the new movie "Lovelace" ... trying to block its release -- no pun intended.

Arrow Productions -- which owns the copyright to the most famous porn flick ever -- is crying foul play because "Lovelace" includes 3 scenes from the seminal skin flick -- no pun intended.

According to the lawsuit -- obtained by TMZ -- Arrow originally allowed producers of a similar film called "Inferno" to use scenes from the porn. Problem was -- funding for "Inferno" dried up. That's when the plan for "Lovelace" was hatched, but Arrow says it didn't give permission for that project.