19 CFR 142.47: Examinations of Line Release transactions.

(a) General. Merchandise imported under Line Release generally may be released without further CBP processing. CBP, however, may choose to inspect any Line Release shipment. Examinations may be either specifically ordered by the CBP officer or random.

(b) Voiding of Line Release transaction. CBP may void a Line Release transaction for the following reasons: Because of an examination, because a carrier transporting the Line Release merchandise is not a participant in a CBP-approved industry partnership program, or because a driver or conveyance is not authorized in accordance with the LBCIP. If this occurs, CBP will return the invoice to the carrier, and the entry filer, in order to enter merchandise, must prepare and submit either a CF 3461 or 3461 Alternate, or its electronic equivalent.