I would like to ask about this encryption method that I found: USPTO patent and it is related to this question here: A service that claims beyond army level encryption and Unseen.is encryption claims revisited with their proprietary, patented “xAES” algorithm. Didn't see any updates on this matter for a long time, so after I had found the patent had appeared online, wanted to ask you experts what do you think about this? Have we found an quantum computing resistant encryption method for the future generations? Thank you in advance.

Example chapter from the patent documentation:

[0020] While the example above uses the simple Caesar cipher in association with a key for encryption, more complex encryption algorithms such as NTRU, Advanced Encryption Standard (AES), and extended Advanced Encryption Standard (xAES), also use a key as mentioned above in order to encrypt and decrypt data. It should be noted that the encryption algorithm 106 may use any one of these encryption algorithms in accordance with an embodiment of the present invention. The keys associated with these encryption algorithms are significantly more complex than the Caesar cipher and have considerably more characters. Nonetheless, these advanced encryption algorithms use the same principles as the Caesar cipher during encryption and decryption processes. More specifically, each of these encryption algorithms processes data using the encryption algorithm and a key during encryption and decryption. However, the key used with these encryption algorithms have a finite number of bytes. In many instances, these encryption algorithms use a key having 256 bytes, or 32 characters, that are generated using a random number generator. Based on this finite number of keys, unauthorized third parties may correctly guess the key and then, in conjunction with the encryption algorithm, decrypt the encrypted content. In other words, unauthorized third parties may use the key with the encryption algorithms noted above to decrypt encrypted data.

Patent image 1

  • Just to be clear, you want the community to comment on whether this is a quantum computing resistent encryption method based on the description in the patent?
    – Jedi
    Commented Jun 29, 2016 at 17:26
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    Hi Jedi. Thank you for pointing that out. What I am searching here is merely of an understanding of what the service "thinks" it is selling. And as a customer, what am I "thinking" I am buying. Because the service presents their encryption to be beyond AES 256 and that they supposedly have been able to create something much stronger than that, which supposedly could even withstand known attacks with even using quantum computing power. For the user of the service, how valid these claims may be? What are they actually selling, that interests me. Unsubstantiated or substantiated claims? Commented Jun 29, 2016 at 17:31
  • Probably relevant: Schneier on Snake Oil and a Snake Oil contest. The only way this could be substantiated is if they put themselves up for public scrutiny, with an open source implementation, list of tests performed, and set up a public bounty/pentest program. It's unlikely that people will be motivated to spend much time deciphering a USPTO filing.
    – Jedi
    Commented Jun 29, 2016 at 17:40
  • Thank you Jedi. What you say speaks for the fact that they want to "look professional" in what they are doing and file a patent and then appear more "serious". Or am I completely mistaken? What is the value for patenting an encryption method that nobody else but the patent office can validate? Furthermore; when and if patented, is it then possible to do the public review or does it mean they still can hold it as their "secret" and never reveal any more details of their "patented" encryption? "It's patented, it's secure"? Commented Jun 29, 2016 at 17:53
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    Related post: security.stackexchange.com/questions/101841/…
    – Jedi
    Commented Jul 9, 2016 at 5:31

2 Answers 2


An encryption patent is a contradiction in terms these days. Nobody (in the large) is going to spend the effort to evaluate a patented method. At best, you would read the patent filing and determine that it's a cheesy version of something that exists and expose yourself to triple damages because you read a patent that should have been rejected based on an immense amount of prior art that should have been discovered, but wasn't because the filing is basically dishonest about this.

  • Thank you Rob. What is the difference to AES having been also patented (google.com/patents/US7421076) to what Unseen.is tries to do with their Multidimensional-Encryption? Could they become the next "AES"? Commented Jun 30, 2016 at 6:19
  • the environment has changed a lot. people used rsa for a while, and were simultaneously dealing with export issues. if you include legally encumbered anything in your design, it's going to get rejected until there is no other option.
    – Rob
    Commented Jun 30, 2016 at 6:23
  • i dont think that means that aes is patented at all. that looks like a patent for a particular implementation of it, which hardware vendors are ok with; because they will send their designs to somebody else to manufacture. but these days, the algorithm is not considered interoperable if both sides need to license it.
    – Rob
    Commented Jun 30, 2016 at 6:39
  • from NIST page on AES: "The call stipulated that the AES would specify an unclassified, publicly disclosed encryption algorithm(s), available royalty-free, worldwide. "
    – Rob
    Commented Jun 30, 2016 at 6:42
  • Thank you Rob for the more specific details on this. I agree, that is not the AES patent, merely AES+something. Just as if Unseen.is patents their xAES maybe. This means, they have the royalty-free AES included. Can basically anyone then take the AES and make an additional encryption block to accompany it then name the whole thing as whatever xAES, yAES etc and patent it? Why don't you and me do the same and establish a web service and offer "beyond military encryption" and people are like "ooooooh" ;P ? Commented Jun 30, 2016 at 7:06

I've tried to analyze the patent, and it seems to address the issue of:

Often In an example where the key has 256 bytes, the algorithm will iteratively guess keys that have 256 bytes. At some point, the algorithm will guess the correct key and the unauthorized third party may access the encrypted data using the correct key.

That's a feature, not a bug - of course one of the 2^256 keys has to decrypt the data!
Since brute-forcing a 256-bit key is essentially impossible, it's a problem that didn't need solving. But as far as it goes...
What the patent itself covers is a key expansion algorithm:

Embodiments of the present invention expand the size of a key that is used with an encryption algorithm to any size extending to infinity that may be used with numerous types of encryption algorithms.

The expansion algorithm appears quite straightforward:

In particular, instead of using a fixed value as the key that is used in conjunction with the encryption algorithm, a variable polynomial is used to generate the key. An example of a polynomial that is used to generate a key is as follows: a(x)=18x 15+11x 14+22x 13+24x 12+10x 11+16x 10+6x 9+22x 8+17x 7+12x 6+6x 5+14x 4+28x 3+5x 2+7x+2

The security of encryption depends on the size of the secret, not the key. When the key is randomly generated and stored, they're the same. When the key is derived from a password, the secret is much smaller (so slow PBKDF and other measures are used to improve security). Since the algorithm should be assumed known to the attacker, the maximum security of the described key would be equivalent to the size of x. The polynomial's coefficients can be seen as a tweak t.

In other words, at best, this invention is appears to be a convoluted form of LRW mode encryption. At worst, the key derivation algorithm employed could reduce the cipher's security.

It definitely isn't a security improvement over known and common encryption modes such as GCM.

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    The patent says 256 bytes, not 256 bits (just makes it seem more like they don't know what they're talking about).
    – forest
    Commented May 14, 2018 at 7:15

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