And comment 229.13(e)-2.d.:
d. There are reasons that may cause a bank to believe that a check is uncollectible that are based on confidential information. For example, a bank could conclude that a check being deposited is uncollectible based on its reasonable belief that the depositor is engaging in kiting activity. Reasonable belief as to the insolvency or pending insolvency of the drawer of the check or the drawee bank and that the checks will not be paid also may justify invoking this exception. In these cases, the bank may indicate, as the reason it is invoking the exception, that the bank has confidential information that indicates that the check might not be paid.
And comment 229.13(g)-5:
5. Record retention. A depositary bank must retain a record of each notice of a reasonable cause exception for a period of two years, or such longer time as provided in the record retention requirements of §229.21. This record must contain a brief description of the facts on which the depositary bank based its judgment that there was reasonable cause to doubt the collectibility of a check. In many cases, such as where the exception was invoked on the basis of a notice of nonpayment received, the record requirement may be met by retaining a copy of the notice sent to the customer. In other cases, such as where the exception was invoked on the basis of confidential information, a further description to the facts, such as insolvency of drawer, should be included in the record.
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