Your private key is very secure. We print the private key once, and after printing, immediately destroy the source file and wipe printer memory. Therefore you alone have the key. In case you need to spend your coin, your private key is located under the hologram. In addition, we generate the keys themselves on a computer that is always offline.
We highly supervise the process of assembling Denarium Bitcoin. Each phase of the assembly that involves the handling of private keys is directly supervised.