What is SEC?

SEC is short for the US securities regulator that oversees investment advisers and broker-dealers. Providers in the US usually list it in their regulatory details, often next to FINRA and a protection scheme such as SIPC or FDIC.

Betterment describes itself as an SEC-registered investment adviser, with its broker-dealer side a FINRA member and SIPC membership. Composer lists SEC, FINRA and SIPC, and Ally Bank lists SEC, FINRA and FDIC, which includes the SEC together with FINRA and FDIC. Bitazza Thailand instead cites Thai SEC licensed as a digital asset broker by Thailand's Ministry of Finance, where the Thai SEC is the digital asset broker licence granted by Thailand's Ministry of Finance.

Different markets, different regulators. Reading the list tells you which authority answers questions about a provider.