What are SEC and FINRA's electronic records requirements for broker-dealers, and what does WORM storage have to do with Rule 17a-4?

Broker-dealers in the United States operate under some of the most detailed recordkeeping obligations of any regulated industry. Two bodies set the rules: the Securities and Exchange Commission (SEC), which writes the federal regulations, and the Financial Industry Regulatory Authority (FINRA), the self-regulatory organization that supervises member firms and enforces its own complementary rules.

What the SEC requires

The SEC’s core recordkeeping rules for broker-dealers are commonly cited as Rules 17a-3 and 17a-4 under the Securities Exchange Act. In broad terms:

• Rule 17a-3 describes which books and records a firm must create — order tickets, account records, trade blotters, communications, and similar documents.
• Rule 17a-4 governs how long those records must be preserved, how they must be stored, and how they must be made available to regulators on request.

Retention periods vary by record type, with many records kept for several years and some required to be readily accessible for a defined initial period.

Where WORM storage fits in

Rule 17a-4 has historically required that electronic records be preserved in a non-rewriteable, non-erasable format. This is the principle behind WORM — Write Once, Read Many — storage. The goal is integrity: once a record is committed, it cannot be altered or deleted before its retention period expires, so regulators can trust that what they review is the original.

Importantly, WORM is an outcome requirement, not a specific technology. Traditional optical media satisfied it, and the SEC has more recently recognized that software-enforced controls (sometimes called an audit-trail or electronic-recordkeeping alternative) can also meet the standard, provided alteration and premature deletion are prevented and verifiable.

How FINRA complements the SEC

FINRA rules generally require member firms to retain books and records consistent with SEC requirements and add supervisory obligations, including review and retention of business communications. Firms must also typically designate a third party able to access records if the firm itself cannot.

Practical takeaways

• Treat retention, immutability, and ready access as distinct requirements.
• Confirm exact periods against the current rule text, since they differ by record type and are periodically amended.
• Document your controls so you can demonstrate, not just assert, that records are tamper-evident.

For broader context on managing digital records, see the electronic records topic hub.