Written by: Nitai Sylvetsky
While enabling several major technological developments—such as decentralized digital currencies and secure internet communications—cryptography is often viewed as a branch of mathematics. Patents, however, are intended to protect technological inventions rather than mathematical abstractions. As a result, cryptographic inventions—particularly in cryptocurrency and blockchain systems—can encounter patent-eligibility challenges when claims appear to cover mathematical relationships implemented on computers.
Under modern U.S. patent-eligibility doctrine following Alice Corp. v. CLS Bank International, claims directed primarily to abstract ideas such as mathematical formulas must demonstrate a technological application or improvement beyond routine computer implementation in order to be patent-eligible. Recent decisions continue to clarify how such improvements may be demonstrated—for example, Ex parte Desjardins (September 2025), discussed in a separate article in this newsletter. Cryptographic algorithms—particularly protocols that can, in principle, operate independently of any specific technological infrastructure—may therefore face scrutiny when claimed merely as protocols, rather than as part of a concrete technological implementation.
A recent cryptocurrency patent dispute illustrates this issue. In litigation involving the Bancor and Uniswap decentralized cryptocurrency exchange protocols, the Bancor‑linked Bprotocol Foundation alleged that Uniswap‑linked entities Universal Navigation, Inc. and the Uniswap Foundation infringed Bancor patents covering automated market‑maker technology for pricing token trades. The asserted patent claims relied on a constant‑product pricing relationship governing liquidity pools implemented through blockchain software. In early 2026, a federal court in New York dismissed the case, holding not only that the Bprotocol Foundation failed to state a claim of infringement against the Uniswap‑linked entities, but also that the asserted patent claims were invalid as patent‑ineligible under the Supreme Court’s Alice test. The court determined that “[t]he asserted claims in this case lack any inventive concept” required for patent eligibility, and further noted that the ideas underlying the patents were implemented only “in the context of existing smart contract and blockchain technology.”. See BPROTOCOL FOUNDATION v. UNIVERSAL NAVIGATION, INC., No. 25-CV-4214 (JGK), slip opin. at pg. 19, 2nd paragraph (S.D.N.Y. Feb. 10, 2026).
The case illustrates that improving the likelihood of patent eligibility generally requires more than claiming an abstract protocol or mathematical relationship implemented within existing smart-contract or blockchain infrastructure. Instead, patent applicants should demonstrate a technological improvement in the functioning of computing systems or networks themselves.
Cryptographic systems tied to specific technological environments may therefore present stronger eligibility arguments—a dynamic illustrated by emerging post-quantum cryptography. The prospect that quantum computers could compromise widely used cryptographic systems has prompted the development of new algorithms designed to resist quantum attacks. For example, the National Institute of Standards and Technology has selected lattice-based schemes such as the CRYSTALS-Kyber key encapsulation mechanism through its post-quantum cryptography standardization program.
Although these schemes are themselves mathematical, their deployment often involves system-level engineering challenges, including secure key-exchange mechanisms designed to operate in the presence of quantum adversaries. Implementations may require new protocol-negotiation mechanisms, hybrid classical–post-quantum security architectures, and infrastructure capable of supporting computationally intensive cryptographic primitives. In such cases, the technological environment in which the cryptographic scheme operates may allow for patent eligibility by reasonably being viewed as extending beyond what would be considered a generic computing environment under current standards.
These types of inventions may be framed as technological improvements to secure a specific computing infrastructure, rather than as mathematical algorithms in isolation or algorithms implemented on generic computer systems. Recent decisions such as Ex parte Desjardins illustrate how applicants may demonstrate that computer-implemented inventions improve the functioning of computing systems themselves. (See also the separate article discussing this precedential decision in the current edition of this newsletter.)
As the cryptography community prepares for quantum-capable adversaries, innovation is increasingly focused on system architectures that enable computing systems and networks to operate securely in a post-quantum environment. While mathematical algorithms alone may remain difficult to patent, technologies that enable secure system operation against quantum-enabled threats—such as post-quantum migration architectures, hybrid cryptographic protocols, and improved security infrastructures—may present stronger opportunities for patent protection.
References
- Alice Corp. v. CLS Bank International, 573 U.S. 208 (2014).
Supreme Court opinion:
https://supreme.justia.com/cases/federal/us/573/208/ - BPROTOCOL FOUNDATION v. UNIVERSAL NAVIGATION, INC., No. 25-CV-4214 (JGK), slip opin. (S.D.N.Y. Feb. 10, 2026).
Federal docket: https://law.justia.com/cases/federal/district-courts/new-york/nysdce/1:2025cv04214/642852/92/ - National Institute of Standards and Technology, Post-Quantum Cryptography Standardization Project.
https://csrc.nist.gov/projects/post-quantum-cryptography - CRYSTALS-Kyber key-encapsulation mechanism (selected in the NIST PQC standardization effort).
NIST overview:
https://csrc.nist.gov/projects/post-quantum-cryptography/selected-algorithms-2022 - Ex parte Desjardins, Appeal No. 2024-000567 (PTAB Decision Sept. 26, 2025)
https://www.uspto.gov/sites/default/files/documents/202400567-arp-rehearing-decision-20250926.pdf
