The public comment period is apparently closed on the matter, but implementation of the microstamping law requires certification that the technology is available. Apparently the California DOJ are proceeding with that process:
The lack of available microstamping technology has not deterred the Department of Justice from proceeding with promulgating regulations for the law’s implementation. In other words, these proposed regulations are completely unnecessary at this time. It is on this basis, among others, that the NRA is objecting to the DOJ commencing with the rulemaking process on this matter. The NRA Letter to the DOJ is available to read in its entirety here.
Proceeding despite the fact that the technology isn’t available. This is about fighting crime right? Not a backdoor gun ban?