19 C.F.R. § 165.24

(a) Reasonable suspicion. No later than 90 calendar days after initiating an investigation under § 165.15, CBP will take interim measures if there is a reasonable suspicion that the importer entered covered merchandise into the customs territory of the United States through evasion.

(b) Measures. If CBP decides that there is reasonable suspicion under paragraph (a) of this section, then:

(1) For entries that remain unliquidated, CBP will:

(i) Suspend the liquidation of each unliquidated entry of such covered merchandise that entered on or after the date of the initiation of the investigation under § 165.15;

(ii) Extend the period for liquidating each unliquidated entry of such covered merchandise that entered before the date of the initiation of the investigation under § 165.15 pursuant to section 504(b), Tariff Act of 1930, as amended (19 U.S.C. 1504(b)); and

(iii) Take such additional measures as CBP determines necessary to protect the revenue of the United States, including requiring a single transaction bond or additional security or the posting of a cash deposit with respect to such covered merchandise pursuant to section 623, Tariff Act of 1930, as amended (19 U.S.C. 1623).

(2) For entries that are liquidated, CBP may initiate or continue any appropriate measures separate from this proceeding.

(c) Notice. If CBP decides that there is reasonable suspicion under paragraph (a) of this section, CBP will issue a notice of this decision to the parties to the investigation within five business days after taking interim measures. CBP will also provide parties to the investigation with a public version of the administrative record within 10 business days of the issuance of a notice of initiation of an investigation.