# FinCEN

> FinCEN (US Treasury · Financial Crimes Enforcement Network): Bank Secrecy Act · the deepest US constraint. Region: Americas. Restricts anonymity: Anonymity-enhancing assets or unattributed transfers are barred outright, or barred for regulated firms.

Part of the Soda Labs Privacy Hub regulation map, which reads the instruments
themselves rather than summarising the summaries: https://www.sodalabs.xyz/privacy-hub/regulation

## Key facts

- Entry type: Regulator or standard-setter
- Region: Americas
- Subject: Bank Secrecy Act · the deepest US constraint
- Authority: US Treasury · Financial Crimes Enforcement Network
- Stance on on-chain confidentiality: Restricts anonymity. Anonymity-enhancing assets or unattributed transfers are barred outright, or barred for regulated firms.
- Tags: Bank Secrecy Act, travel rule, Section 311, mixing rule pending
- Canonical page: https://www.sodalabs.xyz/privacy-hub/regulation/reg-fincen

## What it actually says

Registration, identity verification and suspicious activity reporting for anyone acting as a money transmitter in crypto all originate here, and none of that has loosened. What has changed is the perimeter around it. The two most aggressive proposals aimed at self-custody were both withdrawn: the 2020 unhosted wallet rule in 2024, and the plan to lower the cross-border transfer threshold to USD 250 in 2025. The 2019 guidance also still distinguishes providing an anonymising service from publishing anonymising software, which matters a great deal to developers. The open question is the 2023 proposal to treat mixing as a class of transactions of primary money laundering concern. Nearly three years on it is neither finalised nor abandoned.

## The instruments that matter

- **31 CFR 1010.410(f)**: the travel rule, attaching transmittor name, address, account number and amount to transfers of USD 3,000 or more
- **FIN-2019-G001, 9 May 2019**: consolidated guidance treating exchangers and administrators as money transmitters, while preserving the distinction between an anonymising service provider and an anonymising software provider
- **Unhosted wallet proposal withdrawn April 2024**: and the proposal to cut the cross-border travel rule threshold to USD 250 withdrawn in April 2025
- **The mixing rule is dormant, not dead**: the 2023 proposal to designate convertible virtual currency mixing as a class of transactions of primary money laundering concern drew over 2,200 comments and is now classified a long-term action with final action to be determined

## Sources

- [Travel rule text, 31 CFR 1010.410](https://www.law.cornell.edu/cfr/text/31/1010.410)
- [Section 311 mixing proposal](https://www.federalregister.gov/documents/2023/10/23/2023-23449/proposal-of-special-measure-regarding-convertible-virtual-currency-mixing-as-a-class-of-transactions)

## Related entries

- [EU Transfer of Funds Regulation](https://www.sodalabs.xyz/privacy-hub/regulation/reg-eu-travel-rule): Travel rule · Regulation (EU) 2023/1113
- [FATF](https://www.sodalabs.xyz/privacy-hub/regulation/reg-fatf): The source of almost every travel rule on earth
- [GENIUS Act](https://www.sodalabs.xyz/privacy-hub/regulation/reg-genius-act): Stablecoins · censorability as a licensing precondition
- [IRS broker reporting](https://www.sodalabs.xyz/privacy-hub/regulation/reg-irs-broker-reporting): Tax · live at the custodial perimeter, dead beyond it
- [NYDFS](https://www.sodalabs.xyz/privacy-hub/regulation/reg-nydfs): The most privacy-restrictive US regulator, state or federal
- [The third-party doctrine](https://www.sodalabs.xyz/privacy-hub/regulation/reg-third-party-doctrine): Why chain analysis needs no warrant