A recent Patent Trial and Appeal Board decision related to hybrid quantum computing paves the way for more quantum computing-related patents, and potential litigation.
Quantum computing is an important and evolving form of computing that has yet to be truly realized. Classical computing is, fundamentally, governed by the ability to store information in a bit, a binary unit represented by a one or a zero. In contrast, quantum computing is governed by a quantum bit, or qubit, which can represent an infinite, continuous number of possible states. For example, while 2 bits can store four combinations (00, 01, 10, or 11), 2 qubits can store all four combinations simultaneously. Hybrid quantum-classical computing (“HQC”) involves using both quantum computing and classical computing together in a system for one to address the shortcomings of the other. At its core, both types of computing are well known and rely on mathematical concepts making patent claims on a HQC highly susceptible to patent ineligibility attacks.
The recent Patent Trial and Appeal Board (“PTAB”) decision, Ex parte Yudong Cao, provides insight for patent applicants faced with Patent Office rejections of HQC claims. In the instant case, Yudong Cao was the co-founder and CTO of Zapata Computing, Inc., a now-defunct startup that specialized in quantum computing and artificial intelligence. Cao’s patent application relates to an HQC system that solves linear systems by splitting them into subsystems using classical computing, solving the subsystems using quantum computing, and synthesizing the outputs of the quantum computer using a classical computer.
The Examiner had rejected the HQC claims under Section 101 of the Patent Act as directed to the abstract idea of mathematical relationships, and because the additional elements of the claim — “on a quantum computer, controlling a plurality of qubits, according to the set of circuit parameters 𝜃⃗, to prepare a quantum state |ψ(𝜃⃗)⟩” — allegedly failed to integrate mathematical relationships into a practical application. The PTAB disagreed with the Examiner and reversed the rejection because “the additional element integrates the abstract idea of mathematical relationships into a practical application of enabling noisy quantum computers, which have limited circuit depth, to practically solve linear systems – a technology improvement.” The Specification described deficiencies in the prior art which prevented quantum computers from solving linear systems. The combination of classical computing with quantum computers to form hybrid quantum-classical computer systems to solve linear systems was the technological advancement. And for these reasons, the “additional element” in the claim appropriately integrated the abstract idea (mathematical relationships) into a “practical application” to overcome the 101 rejection.
The Ex parte Yudong Cao PTAB decision comes on the heels of recent announcements in the field of quantum computing by some of the world’s biggest tech companies, Amazon, Google, and Microsoft. Amazon Web Services, for example, claims its first quantum computing chip, Ocelot, can lower the costs of quantum computers by up to 90%. Similarly, Google claims its quantum computing chip, Willow, represents significant advances in solving error-correction problems ubiquitous in quantum computing. Microsoft, on the other hand, announced that its quantum computing chip, Majorana 1, is enabled by a first-of-its-kind topological superconductor material, or topoconductor.
Takeaway
The significant investments in quantum computing by the world’s biggest companies and emerging start-up companies are driving an uptick in efforts to secure intellectual property protection in the form of quantum computing-related patents. Section 101 of the Patent Act has historically been a major hurdle for patent applicants attempting to claim improvements that enhance a computer’s ability to solve mathematical problems. Now, quantum computing and HQC patent applicants find guidance in (and can direct Examiners to) decisions like Ex parte Yudong Cao to articulate the patentability of their inventions. In the coming decade, with more quantum computing and HQC issued patents, we will likely observe an uptick in patent litigation as both large established corporations and start-ups seek to enforce and monetize their advancements in quantum computing technology.