FINRA Rule 6810

FINRA designed several definitions in this original filing to permit continuity with existing market infrastructure rather than forcing entirely new identification systems. The "SRO-Assigned Market Participant Identifier" concept, for example, allows an Industry Member to use any existing identifier already assigned by a self-regulatory organization, such as a FINRA MPID, a Nasdaq MPID, an NYSE Mnemonic, a CBOE User Acronym, or a CHX Acronym, when reporting order information to the Central Repository, rather than requiring firms to obtain an entirely new, CAT-specific identifier for this purpose.

The 2020 Amendment: Privacy Relief and ATS Expansion

FINRA amended Rule 6810 significantly in 2020, under SR-FINRA-2020-029, approved by the SEC on November 12, 2020, in a filing that accomplished two distinct things simultaneously. First, it implemented what FINRA calls the "Modified PII Approach," adding a definition of "Transformed Value for individual taxpayer identification number (ITIN)/social security number (SSN)" to Rule 6810, reflecting the SEC's exemptive relief eliminating the requirement to report a customer's raw Social Security Number or date of birth to CAT. Under this modified approach, Industry Members instead report a transformed, non-reversible representation of the tax identifier along with the customer's year of birth rather than the full date, and the definition of "Customer Account Information" was correspondingly adjusted to reflect this reduced sensitivity of the underlying data being collected.

Second, the same 2020 filing added a definition of "ATS" to Rule 6810 specifically to extend CAT's reporting requirements to alternative trading systems trading OTC Equity Securities, not merely those trading NMS stocks as had previously been the case. FINRA explained that ATSs trading NMS stocks were already reporting comparable information to the Order Audit Trail System, meaning extending the same reporting obligation to CAT imposed relatively little additional burden on them, while extending the requirement to OTC Equity Security ATSs served FINRA's stated goal of being able to reconstruct ATS order books and conduct surveillance across the full range of ATS activity, not just the NMS stock segment. This expansion was also explicitly tied to FINRA's broader plan to retire OATS entirely once CAT reporting had matured sufficiently, a retirement that in fact occurred the following year and is documented in the Rule 7400 entry elsewhere in this dictionary.

This same filing added "Introducing Industry Member" to Rule 6810, defining it as a broker-dealer that does not qualify as a Small Industry Member solely because it satisfies SEA Rule 0-10(i)(2) by introducing transactions on a fully disclosed basis to clearing firms that are not themselves small businesses or small organizations. FINRA created this category specifically so that introducing firms relying on larger clearing firms would still receive the more accommodating Small Industry Member compliance schedule under Rule 6895, even though they do not independently qualify as small businesses themselves.

Continued Refinement: Phased Reporting and Allocation Definitions

Rule 6810 has continued to accumulate additional definitions as CAT's phased implementation has progressed. FINRA added a definition of "Phase 2e Industry Member Data" to address the final phase of Industry Member Data reporting contemplated by the CAT NMS Plan, describing it simply as the Industry Member Data required to be reported commencing in that phase, with the full scope of CAT NMS Plan requirements not becoming operative until Phase 2e is actually implemented, subject to any exemptive relief or Plan amendments in effect at that time.

More recently, FINRA proposed adding a definition of "Allocation" to Rule 6810, alongside a corresponding amendment to the existing "Allocation Report" definition, to align the Compliance Rule with an SEC conditional exemption from certain allocation reporting requirements otherwise imposed by the CAT NMS Plan. That same proposal eliminated a specific technical requirement, the prime broker SRO-Assigned Market Participant Identifier reporting and recordkeeping obligation for executing brokers, illustrating how Rule 6810's definitions continue to evolve in tandem with substantive relief the SEC and the CAT NMS Plan's Operating Committee grant from time to time.

The 2025 Privacy and Reporting Relief Developments

CAT's data collection scope has continued to narrow in the direction of reduced personally identifiable information even beyond the 2020 Modified PII Approach. On March 13, 2025, the CAT NMS Plan's Operating Committee filed a further amendment, later amended on May 28, 2025, that would eliminate the requirement for Industry Members to report customer names, customer addresses, and years of birth for natural persons whose Social Security or tax identification numbers are already reported using the Transformed Value approach, extending to both individuals with and without transformed identifiers as well as legal entities. The SEC separately issued exemptive relief in 2025 specifically addressing the reporting of certain customer information to the CAIS component of CAT for what the Plan refers to as Designated Natural Persons, with FINRA issuing CAT Alert 2025-02 to guide Industry Members through the reporting alternatives this relief makes available.

FINRA and the CAT NMS Plan Participants have also continued to narrow the scope of verbal and manual activity subject to CAT reporting. On June 16, 2025, the SEC approved amendments exempting several categories of verbal and manual activity from CAT reporting requirements, at least until July 31, 2030: floor broker verbal announcements of firm orders on an exchange that are otherwise reported as systematized orders, market maker verbal announcements of firm quotes on an exchange trading floor, telephone discussions between an Industry Member and a client that may involve firm bid and offer communications, and unstructured electronic or verbal communications not currently captured by an Industry Member's order management or execution systems, such as electronic chats or text messages. This relief is explicitly time-limited, meaning firms should not assume it represents a permanent narrowing of CAT's scope; the underlying SEC order expires in 2030, after which this activity may become reportable absent further relief.

Scope Limits Worth Understanding Precisely

Rule 6810's "Eligible Security" definition includes all NMS Securities and all OTC Equity Securities, but this broad scope carries an important practical limitation connected to timing rather than security type itself. Restricted equity securities effected pursuant to Securities Act Rule 144A are not required to be reported to the OTC Reporting Facility within the standard 10-second window that ordinary OTC Equity Securities carry, since Rule 144A securities instead follow the longer, next-business-day reporting framework discussed in the Rule 6622 entry elsewhere in this dictionary. Because CAT's reporting framework is built around the same underlying trade reporting infrastructure, this timing distinction carries through: Rule 144A restricted equity securities are not reportable to CAT in the same manner as ordinary OTC Equity Securities, illustrating how a definition that appears comprehensive on its face, covering "all OTC Equity Securities" without qualification, in practice excludes certain security types once the interacting timing rules from other parts of the FINRA rulebook are properly accounted for.

The Broader Funding Context Firms Should Watch

While CAT's funding mechanics live primarily in Rule 6897 rather than Rule 6810 itself, firms tracking CAT compliance should be aware that the underlying CAT NMS Plan funding model has become the subject of significant, ongoing industry dispute at the SEC level, with direct relevance to how the broader CAT program, and by extension the definitions Rule 6810 establishes, continues to evolve. Industry commenters including major trading firms and industry associations have raised pointed concerns about a proposed executed-share-based funding model, arguing it may disproportionately burden retail trading activity in lower-priced securities and questioning whether FINRA's own approach to funding its share of CAT costs is adequately justified. This dispute illustrates that CAT remains a genuinely live, contested regulatory program rather than a settled, static piece of infrastructure, and firms should expect continued amendment activity across the Rule 6800 Series, including further refinements to Rule 6810's own definitions, as this and related disputes work their way through the SEC's rulemaking process.

Relevance Across FINRA's Exam Programs

The SIE, Series 63, and Series 65 do not test Rule 6810's definitions, since these exams do not reach into the technical infrastructure underlying market-wide order and trade surveillance systems. A Series 7 candidate gains only tangential value here, mostly in recognizing that CAT exists as a comprehensive market surveillance system distinct from the trade reporting facilities tested more directly elsewhere on the exam.

A Series 24 candidate supervising any trading activity in NMS Securities, OTC Equity Securities, or Listed Options needs genuine command of these definitions, since correctly classifying whether a given order or event qualifies as a Reportable Event, whether a firm is an Industry Member, Small Industry Member, or Introducing Industry Member, and whether a specific transaction type falls within an available exemption all trace back to how Rule 6810 defines these terms. A Series 57 candidate handling order entry, routing, or execution needs working fluency with the SRO-Assigned Market Participant Identifier concept and the Order definition specifically, since these terms determine what information a trader's own systems must capture and report as part of the CAT-Order-ID linkage the Central Repository relies on to reconstruct an order's complete lifecycle.

What FINRA's Own Examination Findings Reveal

FINRA's 2026 Annual Regulatory Oversight Report catalogs a specific, recurring set of CAT reporting deficiencies worth understanding directly, since these findings reveal where firms most commonly struggle to correctly apply the Rule 6810 definitions in practice rather than merely listing abstract categories of potential noncompliance. FINRA has cited incomplete submission of Reportable Events, including missed new order, route, and execution events; failure to repair identified errors within the required T+3 correction deadline; failure to submit corrections for previously inaccurate data, including data that did not generate automated error feedback from CAT; and inaccurate or incomplete reporting of CAT orders more generally.

FINRA has also flagged supervisory gaps distinct from the underlying reporting errors themselves: firms failing to establish reasonable written supervisory procedures addressing CAT reporting and clock synchronization, whether performed internally or through a third-party vendor; firms using unreasonably small sample sizes, or samples lacking variety across order and event types, when reviewing their own CAT reports for accuracy; firms failing to draw review samples proportionately across all desks, aggregation units, business lines, and order flow types; firms not reasonably supervising Reporting Agents that report to CAT on their behalf; and firms failing to promptly remediate identified CAT reporting issues, whether discovered through their own internal reviews or through a FINRA inquiry. FINRA has separately emphasized recordkeeping gaps, including firms that fail to maintain the underlying books and records supporting their CAT-reported data, and firms that lack a clear internal "map" showing precisely how their own records and blotters correspond to the specific fields ultimately reported to CAT, a gap that becomes especially problematic once a firm needs to investigate the root cause of a reporting discrepancy FINRA has identified.

Practical Guidance for Firms

Given how frequently Rule 6810's definitions interact with substantive obligations found elsewhere throughout the Rule 6800 Series, firms should treat definitional accuracy as a foundational compliance control rather than a one-time classification exercise performed at initial CAT onboarding and then never revisited. A firm's status as a Small Industry Member, Introducing Industry Member, or ordinary Industry Member should be periodically reconfirmed as the firm's own clearing arrangements or business structure evolves, since a change in clearing relationship could shift which compliance schedule and which substantive requirements actually apply going forward, and a firm operating under an outdated classification risks either under-complying with requirements it has actually grown into or over-engineering compliance processes calibrated to a status it no longer holds.

Firms should also build the specific examination findings FINRA has published directly into their own CAT supervisory program design, particularly the recordkeeping "map" concept connecting internal records to CAT-reported fields. A firm that cannot readily demonstrate, field by field, how its own order management system data translates into what actually gets reported to the Central Repository is poorly positioned to catch reporting errors proactively, and is even more poorly positioned to respond efficiently once FINRA identifies a discrepancy during an examination. Given FINRA's specific emphasis on sampling methodology, firms reviewing their own CAT reporting accuracy should ensure their sample selection genuinely spans the full range of order types, event types, desks, and aggregation units the firm actually handles, rather than concentrating review effort on the most familiar or highest-volume order flow while leaving less common but still reportable activity comparatively unexamined.

Firms should also monitor the CAT NMS Plan's continuing evolution closely, given how much of Rule 6810's recent amendment history has been driven by Plan-level exemptive relief rather than FINRA's own independent rulemaking initiative. The 2025 CAIS privacy amendments and the verbal and manual activity relief both originated at the CAT NMS Plan and SEC level before being reflected in FINRA's own Compliance Rule, meaning firms tracking only FINRA's rule filings directly, without also monitoring CAT NMS Plan-level developments and SEC exemptive orders, risk missing changes that will eventually flow through to their own Rule 6810 compliance obligations. This layered governance structure, Plan-level amendments and exemptive relief cascading down into FINRA's Compliance Rule, means a genuinely thorough CAT compliance monitoring program needs to track developments at both levels simultaneously rather than assuming FINRA's own rule filings alone capture the full universe of relevant regulatory change affecting the firm's reporting obligations.