Bitcoin developer monitoring found six OFAC sanctioned transactions that may have been filtered by F2Pool

On November 22nd, Bitcoin developer 0xB10C posted an article stating 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 found 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 misreporting 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.