file off the serial numbers

Meanings:

1.
USUKinternationalinformalslangcriminal
- To remove or obliterate serial numbers or other identifying marks from a physical object in order to conceal its origin or make it easier to sell or traffic illicitly.
2.
USUKinternationalfandom slanginformalidiomatic
- To strip or alter distinctive, copyrighted, or identifying elements from a derivative creative work so that it can be presented, marketed, or claimed as an original or independent work.

EN: "Used" as in previously owned by Blake Wyatt for the time that it took him to buy them from Gerry's Sporting Goods, then file off the serial numbers, and then sell them on to Clay Malone as "stolen,"
ES: "Usadas" por el anterior propietario Blake Wyatt durante el tiempo que le tomó comprarlas en la armería de Gerry, eliminar los números de serie, y después vendérselas a Clay Malone como "robadas", porque los delincuentes pagarán diez veces el precio al público
EN: High-end electronics, you file off the serial numbers and sell them immediately.
ES: En electrónicos, les borras los números de serie y los vendes enseguida.
EN: You and me are gonna grab a couple of motorcycles, file off the serial numbers, head down to Baja, see what kind of trouble we can get into.
ES: Tu y yo vamos a coger un par de motos, borrar los números de serie, ir hasta Baja ver en que tipo de problemas podemos entrar.