Review how Series 4 handles options trade errors, cancel-rebills, obvious errors, and Rule 15c3-5 market-access controls.
The final part of the trading function asks what happens when the trade flow breaks. Series 4 expects the options principal to understand cancel-rebills, error accounts, obvious-error treatment, and the controls around customer market access. This is a classic options-supervision topic because speed and complexity can turn small execution mistakes into larger account or regulatory issues.
The right instinct here is not to improvise. If a trade is in error or if customer market access creates inappropriate risk, the principal should rely on the firm’s formal correction and control process. The exam usually rewards the answer that uses a defined correction path rather than an informal workaround.