Bitcoin developers have observed that F2Pool appears to be intentionally filtering transactions involving OFAC-sanctioned addresses.

According to BlockBeats news on November 22, Bitcoin developer 0xB10C stated that six Bitcoin transactions from OFAC-sanctioned addresses were not mined by some mining pools, which may indicate intentional filtering. In September and October 2023, the tool detected missing OFAC-sanctioned transactions in six blocks mined by ViaBTC, Foundry USA pool, and F2Pool. After investigation, 0xB10C believes that the missing transactions in ViaBTC and Foundry USA pool may be due to reporting errors rather than filtering. However, the missing transactions in four blocks of F2Pool are likely to have been intentionally filtered. These transactions are large transactions that merge multiple inputs into a single output, with at least one input coming from an OFAC-sanctioned address.