mail cover

English to Portuguese Law/Patents Law (general) poaching

PLEASE READ NOTE BEFORE MAKING YOUR CONTRIBUTION: I am NOT looking for a **suggestion**. I am looking for an existing, equivalent technical term in Portuguese, preferably European, but a Brazilian term will work too. If no such technical term exists, I will use "cobertura/ajuda dos correios" or some variation of that. ONLY contribute if YOU DO KNOW the equivalent technical term and that is the term you are reporting with a reference.

My apologies for the bluntness.

TERM DEFINITION:
Mail cover is a law enforcement investigative technique in which the United States Postal Service, acting at the request of a law enforcement agency, records information from the outside of letters and parcels before they are delivered and then sends the information to the agency that requested it.