2.3 Trade Error Handling

Key Takeaways

  • Customers may never be disadvantaged by a firm error; the firm absorbs losses and the customer keeps any benefit.
  • Errors are parked in a firm error account that the principal must review and clear promptly so positions do not age.
  • Each error requires a written error report capturing nature, cause, correction, and financial impact.
  • Recurring error patterns trigger root-cause analysis and possible additional representative training.
  • The error account is a firm proprietary account and may not be used to warehouse or speculate on positions.
Last updated: June 2026

The Governing Principle: Make the Customer Whole

The single most tested idea in this section is the customer protection rule: a customer must never be disadvantaged by the firm's error. If a mistake costs the customer money, the firm absorbs the loss; if the mistake happens to benefit the customer, the customer keeps the gain. The supervisor's job is to enforce this before any “as-of” correction is booked.

Common Options Trade Errors

Options errors are easy to make because every contract has four moving parts – underlying, expiration, strike, and type.

ErrorTypical Cause
Wrong seriesBought Jul 50 calls instead of Jun 50 calls
Wrong sideSold a put when the customer said buy
Wrong quantityEntered 100 contracts instead of 10
Wrong accountTrade booked to the wrong customer
Wrong open/closeSTO marked as STC, distorting margin
Wrong priceLimit price keyed incorrectly

Worked example: A representative buys 10 XYZ calls for Customer A that should have gone to Customer B. The supervisor moves the position into the firm error account, then re-executes the correct trade to Customer B at the price Customer B should have received. If the market moved against Customer B in the interim, the firm – not Customer B – eats the difference. Customer A is removed from the trade entirely.

Resolution Workflow

StepSupervisor's Action
1. IdentifyConfirm an error occurred and pin down its exact nature
2. ContainMove the erroneous position into the firm error account
3. DocumentOpen a written error report with full details
4. CorrectExecute the offsetting/correcting trades
5. AllocateBook the position to the correct customer at the correct price
6. ApprovePrincipal reviews and signs off on the resolution

The Firm Error Account – Rules and Limits

The error account is a firm proprietary account used to temporarily hold defective trades while they are corrected. The exam tests several abuses the supervisor must prevent:

  • It may not be used to warehouse positions a representative wants to hold for later, or to speculate.
  • Positions must be cleared promptly; aging positions in the error account are a red flag for examiners.
  • Profitable “errors” that are repeatedly steered into the firm account suggest cherry-picking and require investigation.
  • All activity must be reviewed by a principal on a regular schedule, with documentation.

Documentation and Pattern Analysis

Each error report should capture the following so compliance and examiners can reconstruct what happened:

ElementDetail Recorded
WhatDescription of the error and the series involved
WhoRepresentative, customer(s), reviewing principal
WhenTime discovered vs. time of original trade
How fixedCorrecting trades and final allocation
ImpactDollar gain/loss and who bore it
PreventionSystem or training change to stop recurrence

Individual errors are reviewed as they occur, but the supervisor must also analyze trends. If one representative or one entry system generates repeated wrong-series or wrong-quantity errors, that is a root-cause and training issue – not just a series of isolated fixes. Material customer harm or systemic failures may rise to the level of a reportable event for compliance and, where required, regulators.

How Errors Surface – and Why Speed Matters

Because options decay, an error caught an hour after entry costs far less to fix than one caught on the monthly statement. Supervisors should know the typical discovery channels so they can shorten the lag.

Discovery SourceExample
Real-time system alertOrder-entry engine flags a quantity mismatch
Daily supervisory reviewPrincipal spots a wrong-series fill on the blotter
Customer complaintCustomer reports a trade they never authorized
Statement reviewCustomer notices an unexpected position
Clearing/OCC reconciliationPosition break reported by the clearing firm

The earlier in this chain an error is caught, the smaller the firm's loss exposure under the customer-protection rule – which is precisely why the firm invests in pre-trade alerts and same-day review.

Reporting Tiers

Error reporting flows in tiers. Routine errors are captured in an error log reviewed by the branch manager and compliance. Significant errors – large dollar impact or those affecting multiple customers – go to senior management. Pattern analysis is escalated to the compliance department for root-cause work and training decisions. Where an error reflects a rule violation, material customer harm, or a systemic control failure, compliance evaluates whether a regulatory filing is required.

Exam framing: The Series 9 will not ask you to compute the exact dollar adjustment. It tests judgment – who keeps the gain, who eats the loss, where the position is parked, and what the supervisor must document. Anchor on “customer made whole, firm absorbs its own mistakes, positions cleared promptly, everything documented,” and the error questions become straightforward.

Test Your Knowledge

A firm error causes a customer to receive a worse execution price than they should have. After the customer is made whole, who bears the resulting financial loss?

A
B
C
D
Test Your Knowledge

Which use of the firm's error account would most concern a supervising principal?

A
B
C
D