There was recently discovered a Chinese patent application CN 109981485 A which is about detecting V2Ray, a circumvention system.

• China Digital Times article
• v2ray/v2ray-core issue #1898

I looked at a Google Translate version of the patent application. It is very short, and not very specific. It seems to be about a method of training a machine learning classifier more than anything. It mentions using deep convolutional neural networks, one with a long memory and one with a short memory, trained on the first 16 packets, which is apparently where a key exchange with a distinctive fingerprint happens.

The GitHub discussion seems to say that the patent application only applies to one of V2Ray’s sub-protocols, VMess.