The ATF can narrow it down to who owns what gun if it was purchased through an FFL holder. They don't need to register them.
Thats just who purchased it, not who owns it.
Some more Oregon greatness. Unless gifting to a "close" family member, all transfers are to be done through an FFL. Even to temporarily loan a hunting buddy a rifle cause something happened to theirs, then FFL transfer back into your possession. All firearm transactions are documented in this state. If they track it to you and you don’t have it, you best have a silver tongue to get out of that mess.
All of this done without public involvement or witness as required per the state constitution and with an emergency clause in the legislation so it doesn’t go to a vote of the citizenry. Not a vote with out a 1.5 - 3 years long process to get on the ballot.
Owl