Consolidated Audit Trail (CAT) Reporting in 2026: A Compliance Overview for Broker-Dealers

*A practical guide to Consolidated Audit Trail (CAT) reporting for broker-dealers, clearing firms, and prop trading firms navigating FINRA CAT obligations in 2026.*

If your firm is a FINRA member that handles orders in NMS securities or OTC equities, you are a CAT reporter — and in 2026 that obligation is no longer new, no longer novel, and no longer forgiving. Regulators have moved from onboarding-era leniency to enforcement, error-rate scrutiny, and pointed questions about who owns the data. This guide explains what the Consolidated Audit Trail requires, where firms most often fall short, and how to build a reporting stack that actually holds up in an exam.

What is the Consolidated Audit Trail (CAT)?

The Consolidated Audit Trail is the industry-wide order and customer database mandated by SEC Rule 613 and implemented under the FINRA 6800 Series rules. It captures the complete lifecycle of every order in NMS securities and OTC equities — from origination, through every route, modification, cancellation, and execution — and links that activity to the customers and accounts behind it. The system is operated by FINRA CAT, LLC on behalf of the SROs, and it replaced OATS entirely in 2021.

CAT has two data domains that firms must think about separately:

• CAT Order Data—the order lifecycle events reported by industry members and exchanges. This is what most people mean when they say "CAT reporting."
• CAIS (Customer and Account Information System)—the customer and account attributes that let regulators link order activity to a specific customer identifier. CAIS is part of CAT but has its own file formats, deadlines, and error handling.

Both matter. A firm can be technically current on order reporting and still be out of compliance because its CAIS data is stale, unlinked, or wrong.

Who has to report to CAT?

CAT reaches virtually every FINRA member that touches an order in a reportable security:

• Broker-dealers—that receive, originate, route, modify, cancel, or execute orders in NMS securities (equities and listed options) or OTC equities.
• Clearing firms—whose MPIDs appear in the routing chain.
• Introducing brokers—, even when a clearing firm handles the execution — both parties typically have reporting obligations for the events they touch.
• Prop trading firms operating as broker-dealers—and any registered entity in the order path.
• National securities exchanges and ATSs—for the events they see.

Small "Small Industry Members" have a lighter phased schedule for some elements, but the core obligation to accurately report the events a firm handles is universal. If an order carries your MPID, CAT applies to you.

What has to be reported

CAT is deliberately comprehensive. In broad strokes, industry members must report:

• Order events—new orders, routes (including internal routes), modifications, cancellations, executions, and allocations.
• Timestamps—event times to the level of granularity the firm captures (millisecond, and microsecond where the firm's systems support it), synchronized to NIST within tight tolerances.
• Order attributes—symbol, side, quantity, price, order type, time-in-force, capacity, handling instructions, special handling codes, and the linked parent/child relationships across routes.
• Participant identifiers—the reporting IMID, the routing and receiving parties, and the exchange or venue where relevant.
• Customer and account linkage—the CAT Customer ID (CCID) and Firm Designated ID (FDID) that tie an order back to the customer record in CAIS.
• Representative order handling—bunched, aggregated, and represented orders, with the linkages that let regulators unwind them.
• Options-specific data—complex order legs, auction events, and the additional attributes options orders require.

The reporting cadence is daily: events for trade date T are due by 8:00 a.m. Eastern on T+1, and firms have until 5:00 p.m. Eastern on T+3 to correct rejected records without the correction counting toward their error rate scorecard.

CAIS: the customer-and-account side of CAT

CAIS is where the customer identity behind an order lives. Firms submit and maintain records that map each FDID — a firm-designated identifier assigned to an account — to the underlying CAT Customer ID (CCID) and to standardized customer attributes (name, address, date of birth or entity identifiers, and account type). The CCID is derived from transformed identifiers so raw PII does not sit in the reporting pipeline the same way order data does.

Two CAIS realities catch firms off guard in 2026:

• CAIS drives the linkage.—If a customer's CAIS record is missing, unlinked, or wrong, otherwise-clean order reports become unlinkable and count against the firm.
• CAIS is not one-and-done.—Account openings, closures, address changes, name changes, and account-type changes must flow into CAIS on a rolling basis. Static, onboarding-time submissions are a common exam finding.

Timestamps, clock sync, and data quality

CAT is a data-quality regime as much as a reporting regime. Three technical requirements do most of the work:

• Clock synchronization.—Business clocks used to record reportable events must be synchronized to the National Institute of Standards and Technology (NIST) atomic clock within the tolerance set by FINRA — currently 50 milliseconds for most systems, with tighter expectations where the firm's systems capture finer granularity.
• Timestamp granularity.—Firms must report timestamps at the finest level of granularity their systems capture, up to and including microseconds.
• Event linkage.—Every child order must link cleanly to its parent, every route to its receipt, every execution to the order that produced it. Broken linkages are treated as data-quality errors even when each individual record is well-formed.

Error correction and the CAT error rate

FINRA CAT rejects records that fail validation and returns errors to the submitting firm. The rules give firms a defined window to repair them:

• T+3 by 5:00 p.m. Eastern—corrections submitted by this cutoff do not count toward the firm's error rate.
• After T+3—uncorrected records contribute to the firm's error rate, which is measured against thresholds and reviewed by regulators.
• Repeat and systemic errors—patterns that suggest a broken control or a bad mapping draw supervisory attention independent of the raw error percentage.

A defensible program treats the error file as a daily operational input, not a monthly clean-up project.

Where firms most often fall short in 2026

Recent exam themes and enforcement point to a consistent set of gaps:

• Stale or unlinked CAIS records—accounts that changed after onboarding and were never refreshed, or FDIDs that do not resolve to a CCID.
• Missing representative-order linkages—bunched or aggregated orders reported without the parent/child relationships regulators need to unwind them.
• Clock drift on non-primary systems—a strong primary clock but adjacent systems (a middle-office platform, a smart order router, a manual trade blotter) drifting outside tolerance.
• Late corrections—errors that could have been fixed by T+3 sitting in a queue for a week because ownership is unclear between operations, compliance, and technology.
• Vendor black boxes—reliance on a reporting vendor without the firm being able to explain, in an exam, exactly how a specific event was captured, transformed, and submitted.
• Reconciliation gaps—no daily tie-out between the firm's order-management system, its execution records, and what CAT actually received and accepted.
• Options complexity treated as an afterthought—complex order legs, auction events, and market-maker quoting handled by ad-hoc mappings rather than a first-class part of the pipeline.

How to build a defensible CAT reporting stack

A modern, exam-ready CAT program has six layers:

• 1. Audit-quality capture at the source. Order and execution events are captured in the trading path itself, with correct timestamps, participant identifiers, and parent/child links — not reconstructed after the fact from disparate logs.

• 2. A single normalized event store. All reportable events land in one place with consistent schema, so reporting is a transformation over trustworthy data rather than a scavenger hunt.

• 3. Deterministic mapping to CAT/CAIS formats. Field-by-field mappings from internal event types to CAT event types, versioned and reviewable, with the ability to reproduce any past submission from source data.

• 4. Automated CAIS lifecycle. Account openings, closures, and material changes flow into CAIS automatically from the same customer master that feeds the rest of the firm, so FDID-to-CCID linkage stays current.

• 5. Daily reconciliation and error workflow. A tie-out between the firm's own trade blotter, what was submitted, and what CAT accepted — with rejected records assigned to an owner, an SLA, and a documented fix path well inside the T+3 window.

• 6. Immutable, exam-ready evidence. Every submission, correction, and mapping change captured in a tamper-evident log, with dashboards a supervisor can use to answer "what did we send, when, and why" in minutes rather than weeks.

CAT reporting quick reference

How Gato Systems supports CAT and CAIS reporting

Gato Systems' modular platform is designed so CAT reporting is a downstream result of clean upstream data, not a separate reconstruction project. gHub captures order and execution events in the actual trading path with correct timestamps and parent/child linkages, so the source data is CAT-quality from the start. gPrecision enforces pre-trade controls in the same path, giving every event a defensible audit context. gReg owns the CAT and CAIS reporting pipeline — deterministic mapping, daily reconciliation, error workflow inside the T+3 window, and immutable submission history. gNexus brings it together with supervisory dashboards and evidence trails that answer exam questions about what was reported, when, and why.

The design principle mirrors what regulators now expect: reporting is only as good as the data underneath it, and the firm — not a vendor — must be able to explain both.

Related reading

• SEC Rule 15c3-5 (Market Access Rule): A 2026 Compliance Guide for Broker-Dealers
• Regulatory Reporting Automation for Fintech
• T+1 Settlement: What Broker-Dealers Need to Know