Beer transferred without payment of tax from one brewery to another brewery belonging to the same brewer may be mingled with beer of the receiving brewery. The brewer may handle the beer transferred in accordance with the requirements of this part relating to beer produced in the receiving brewery.
27 C.F.R. § 25.185
Sec. 201, Pub. L. 85-859, 72 Stat. 1389, as amended ( 26 U.S.C. 5414 )