Does Defendant have an affirmative defense of the "antique firearm" exception?

That leaves Defendant with only the affirmative defense of the "antique firearm" exception on which to rely. Defendant had the burden of production to put that affirmative defense at issue. Royal , 731 F.3d at 338 ; United States v. Cruz , 554 F.3d 840, 850 n.16 (9th Cir. 2009). We need not, and do not, decide whether the affirmative defense is objective (meaning that the firearms date of manufacture, alone, provides the answer) or subjective (meaning that a reasonable belief, even if mistaken, that the firearm was manufactured before 1899 could suffice). Either way, Defendant failed to meet his burden of production. He did not dispute the governments evidence that his gun could not have been manufactured before 1915, and he offered no evidence that he reasonably believed that the gun was manufactured before 1899.