Not quite. The Rimowa registration Nr. is always stamped on the hinge-side of the case. This has been a long standing policy of Rimowa with the alu cases, and continues into the polycarbonate series, including Salsa. You can obtain this Nr. and politely contact Rimowa to verify:
Hello
Could you tell me if the registration number is externally stamped on the hinge side..or internally (on the frame) ?