Final answer:
A broker can keep an uncashed deposit check for a period defined by state escheat laws or industry regulations, typically one to five years, after which it must be dealt with according to state unclaimed property rules.
Step-by-step explanation:
An uncashed deposit check may be kept by a broker for a specific period defined by state laws or industry regulations, after which the check must be either refunded to the issuer or turned over to the state's unclaimed property division.
The exact duration depends on the escheat laws, which vary by state, and on policies set forth by the broker's firm or governing bodies such as the Securities Exchange Commission (SEC) or Financial Industry Regulatory Authority (FINRA). Generally, this period ranges from one to five years. If the check remains uncashed, the money is considered 'abandoned' and is subject to escheatment, being turned over to the state as unclaimed property.