Chinese multinational PC company Lenovo has filed a patent with the U.S. Patent and Trademark Office (USPTO) for a system to “verify integrity of physical documents,” using a "security Blockchain.”

The patent application was submitted in August 2016, but was published late last week on Feb. 15.

The use of digital signatures encoded into documents, as opposed to physical signatures printed with physical ink, provides assurance that the document was not modified after the signing.

The patent’s “Brief Summary” explains that a processor will identify an “integrity symbol” within the document, convert it into an “integrity map,” and then compare the map to the physical document to ensure the document’s integrity.

The security Blockchain, Lenovo writes, would allow one to ensure “that they have the current authentic physical document even if multiple paper copies exist and multiple people have made entries in the chain of modification.” If multiple, fake copies of a physical document came into existence, they would “show up as orphaned blocks in the chain.”

In December 2017, Swiss banking giant UBS filed a similar patent with USPTO for a Blockchain-based system for client IP and user validation.

Although Chinese firm Lenovo’s patent application wasn’t submitted recently, its online release comes as China is in the midst of a general crackdown on all things crypto within the country. China banned all foreign cryptocurrency exchanges in early February, following a September 2017 ban of Initial Coin Offerings (ICO).

However, even with the crypto bans in place, Chinese companies have not stopped looking into the crypto sphere. On Feb. 7, Chinese-based payment service provider LianLian partnered with RippleNet to facilitate faster and less expensive cross-border payments in Europe, the US, and China.