Bank of America is seeking to patent a "partitioned" security system for digital currency wallets that gives different users different levels of access to the stored funds.

The second-largest U.S. bank, based in Charlotte, N.C., filed an application entitled “Multi-Tiered Digital Wallet Security” with the United States Patent and Trademark Office (USPTO) in February 2018. The USPTO published the application last week and lists Manu Kurian, senior tech manager at the bank, as the inventor.

The application describes the handling of digital currency with a multi-tiered wallet interface in a decentralized peer-to-peer network. Users would be prompted to enter one password out of several, and one password would open one tier of the wallet while another password would open a different tier. (Think of a valet key that can open a car door but not the trunk.)

Conceptually, the proposal resembles certain types of multi-signature bitcoin wallets, which have been around for years.

The background section of the application explains that there is a need for better digital wallet infrastructure since private keys can be lost and third parties don’t let users exercise complete control over their currency.

The application points to a multi-tier arrangement as one way to improve security:

To date, Bank of America has won 36 blockchain patent applications, with 31 pending.

Other recent patent applications filed by the bank include one for blockchain "regulation architecture" and another for blockchain architecture to optimize system performance and data storage.

Bank of America image via Shutterstock