Reviewed by Sasha Božič, Licensed Customs Broker

CBP Form 3078 is the Application for Identification Card. CBP uses it to run a background check on people who handle imported goods that haven't cleared customs yet, and to issue the card that lets them into CBP security areas at ports and airports. It is a personnel form. Importers rarely file it themselves, but the people moving their freight often need one.
Under 19 CFR 112.41, every licensed cartman or lighterman, and each of their employees, must carry a CBP identification card while handling imported merchandise that is still in CBP custody. CBP's information collection for the form also lists the other workers who typically apply:
The card has to be on the person whenever they deal with that merchandise, and they show it when a CBP officer asks.
CBP can refer any application for an investigation into the applicant's character. The port director can refuse a card when, in the director's judgment, the person's work with bonded merchandise would put the revenue at risk.
Goods sitting in a bonded warehouse, a container freight station or a foreign trade zone are still in CBP custody. Every person who touches them there needs a valid card, and a lapse at your warehouse or cartage provider can hold up your freight. It is worth confirming with those providers that their staff are carded at each port you use.
Caspian works on the duty side of your imports: auditing entries before and after they're filed and recovering overpaid duty through Post-Summary Corrections, protests and drawback. For the core entry forms, see CBP Form 3461 and CBP Form 7501.
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