Positive, as Bubba pointed out, the forms you fill out for the DROS (dealer record of sale - aka CA background check) are not registration. The DROS is done one per transaction. A transaction can consist of multiple firearms. What it comes down to is the state knows you bought a firearm, but doesn't know the make, model, or serial number. This changes with registration where the make, model, and serial number are stored under your name in a database.