Please take a look at the following cites from Reg. CC. There is a limit on the time you can hold funds for new accounts. Also, be careful about the basis on which you hold funds you think may be uncollectible. You can't base the hold on the fact that in general there's been a lot of counterfeit items.
Hope this helps.
Sec. 229.13 Exceptions.
(a) New accounts. For purposes of this paragraph, checks subject to Sec. 229.10(c)(1)(v) include traveler's checks.
(1) A deposit in a new account--
(i) Is subject to the requirements of Sec. 229.10 (a) and (b) to make funds from deposits by cash and electronic payments available for withdrawal on the business day following the banking day of deposit or receipt; (ii) Is subject to the requirements of Sec. 229.10(c)(1) (i) through (v) and Sec. 229.10(c)(2) only with respect to the first $5,000 of funds deposited on any one banking day; but the amount of the deposit in excess of $5,000 shall be available for withdrawal not later than the ninth business day following the banking day on which funds are deposited; and
(iii) Is not subject to the availability requirements of Secs. 229.10(c)(1)(vi) and (vii) and 229.12.
(2) An account is considered a new account during the first 30 calendar days after the account is established. An account is not considered a new account if each customer on the account has had, within 30 calendar days before the account is established, another account at the depositary bank for at least 30 calendar days.
(e) Reasonable cause to doubt collectibility--(1) In general. Sections 229.10(c) and 229.12 do not apply to a check deposited in an account at a depositary bank if the depositary bank has reasonable cause to believe that the check is uncollectible from the paying bank. Reasonable cause to believe a check is uncollectible requires the existence of facts that would cause a well-grounded belief in the mind of a reasonable person. Such belief shall not be based on the fact that the check is of a particular class or is deposited by a particular class of persons. The reason for the bank's belief that the check is uncollectible shall be included in the notice required under paragraph (g) of this section.
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CRCM