The US Customs and Border Protection (CBP) is ramping up its seizure of Bitcoin ASIC miners, including MicroBT and Canaan devices. CBP last year seized Bitmain Antminer S21 and T21 miners on suspicion that they contained AI chips from restricted chipmaker Sophgo. The seizure is based on 19 USC 1595a (c) (2) (A) and involves unauthorized communications equipment and equipment not certified by the FCC.