Systems and methods are provided for controlling the number of products produced by contract manufacturers in order to prevent unauthorized overproduction. Each authorized device that is produced includes both a serial number and an encryption of the serial number. Each device is configured to decrypt the encrypted serial number and verify the decrypted serial number matches the serial number before the device will function properly. The encryption of the serial number is performed at a secure location outside of the control of the manufacturer, and the encrypted serial number is then transmitted to the manufacturer and stored to the device. Without knowledge of, or access to, the details of the encryption process, the manufacturer cannot independently produce devices with properly encrypted serial numbers. Accordingly, the number of properly functioning devices the manufacturer can produce can be limited by controlling the number of encrypted serial numbers provided to the manufacturer.