Bartholomew Roberts
Moderator
The interpretation of it as SB-specific is because it is a letter ruling. The ATF used to be under the Department of the Treasury. Treasury would issue interpretations of tax law. Because tax law is so complicated and fact dependent, these were called "Private Letter Rulings" because they applied only to the specific person who asked. Treasury, of course, would attempt to make uniform rulings; but often there are tiny factual differences that are difficult to distinguish from the outside that cause different outcomes.
Interpetations of the NFA are also private letter rulings and subject to that same distinction. So while you can assume ATF will apply the law uniformly, you are still guessing as to what ATF might see as a significant fact difference.
For example, until just a few years ago, the ATF took the position that the Supreme Court ruling in Thompson Center Fire applied only to that specific firearm.
Interpetations of the NFA are also private letter rulings and subject to that same distinction. So while you can assume ATF will apply the law uniformly, you are still guessing as to what ATF might see as a significant fact difference.
For example, until just a few years ago, the ATF took the position that the Supreme Court ruling in Thompson Center Fire applied only to that specific firearm.