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PatentWorld
Chapter 32

Quantum Computing

From theoretical foundations to practical hardware

Having examined green innovation and the patent system's response to climate technology across energy, transport, and industrial production, this chapter turns to quantum computing, a domain at the opposite end of the maturity spectrum — small in volume but growing rapidly as hardware implementations move from theory to engineering.

Quantum computing represents one of the most technically demanding frontiers in computing. This chapter examines the trajectory of quantum computing patents — from early algorithmic breakthroughs through the hardware competition among major technology firms to the current effort toward error-corrected, fault-tolerant machines.

Growth Trajectory

Figure 1

Quantum Computing Patents Grew From 1 in 1995 to 660 in 2024, Marking the Shift to Engineering

Annual quantum computing patent count by CPC codes, tracking growth trajectory.

Annual count of utility patents classified under quantum computing-related CPC codes, 1990–2025. The most prominent pattern is the sharp acceleration beginning around 2018, coinciding with advances in superconducting qubit hardware and Google's quantum supremacy announcement in 2019. Grant year shown. Application dates are typically 2–3 years earlier.
The growth in quantum computing patents coincides with increased corporate investment in quantum hardware and software, following milestones in qubit performance and error correction demonstrated in the late 2010s.
Figure 2

Quantum Computing's Patent Share Rose From 0.001% in 1995 to 0.203% in 2024, Growing R&D Allocation

Quantum computing patents as a share of all utility patents, showing growing but modest allocation.

Percentage of all utility patents classified under quantum computing-related CPC codes. The upward trend, while starting from a very low base, indicates a genuine reallocation of inventive effort toward quantum technologies.
The growing share of quantum patents among all patents demonstrates that quantum growth is not merely tracking overall patent expansion; rather, it reflects deliberate investment by technology firms in quantum capabilities.
Figure 3

Quantum Computing Patenting Shows Growing Incumbent Dominance: Incumbents Produced 84.5% of 2024 Patents

Annual patent counts decomposed by entrants (first patent in domain that year) versus incumbents.

Entrants are assignees filing their first quantum computing patent in a given year. Incumbents had at least one prior-year patent. Grant year shown.

Quantum Computing Subfields

Figure 4

Physical Realizations Led With 400 Patents in 2024, While Error Correction Grew From 1 in 1998 to 154 in 2024

Patent counts by quantum computing subfield over time, based on CPC group codes.

Patent counts by quantum computing subfield over time. The data reveal a shift from theoretical algorithm patents toward physical realizations and error correction, reflecting the field's maturation from theory to engineering.
The shift toward physical realizations and error correction patents coincides with the field's transition from algorithmic theory to practical hardware engineering in the 2010s.

Leading Organizations

Figure 5

IBM (570), Google (239), and D-Wave (211) Lead Quantum Computing Patenting

Organizations ranked by quantum computing patent count, showing concentration among few tech firms.

Organizations ranked by total quantum computing patents, 1990–2025. The data indicate strong concentration among a handful of large technology firms that have made significant investments in quantum hardware and software.
The dominance of a small group of major technology firms in quantum computing patenting reflects the substantial capital requirements of quantum hardware research, which demands cryogenic infrastructure, specialized fabrication, and large physics and engineering teams.
Figure 6

Quantum Entrants With Prior Semiconductor Experience Fell From 81.3% (2010s) to 45.5% (2020s)

Percentage of quantum computing assignees with prior semiconductor patents, by 5-year entry cohort.

Prior semiconductor experience measured by whether the assignee filed at least one H01L/H10 patent before their first quantum computing patent. Declining share suggests quantum is attracting new entrants from software and cloud computing rather than traditional semiconductor firms.

Top Inventors

Figure 7

The Top 10 Quantum Computing Inventors Hold 303 Patents Combined, Concentrated at IBM, Google, and D-Wave

Primary inventors ranked by quantum computing patent count, showing expertise concentration.

Primary inventors ranked by total quantum computing patents. The distribution exhibits pronounced concentration, reflecting the highly specialized nature of quantum computing research and the small size of the global quantum workforce.
The concentration of quantum patents among a small number of inventors reflects the specialized expertise required in quantum physics, cryogenics, and quantum information theory — skills that remain scarce in the global labor market.

Geographic Distribution

Figure 8

Canada (265), Japan (144), and China (90) Lead Non-US Quantum Computing Patenting

Countries ranked by quantum computing patents based on inventor location.

Countries ranked by total quantum computing patents based on primary inventor location. The United States maintains a substantial lead, while the presence of Canada, Japan, China, and Israel reflects the global nature of quantum research investment.
The geographic distribution of quantum patents reflects the concentration of quantum research in countries with strong physics traditions and substantial government funding for quantum technologies.
Figure 9

California (682), New York (401), and Maryland (153) Lead US Quantum Computing Patenting

US states ranked by quantum computing patents based on inventor location.

US states ranked by total quantum computing patents based on primary inventor location. The clustering of quantum innovation in California, New York, and a few other states reflects the location of major corporate research labs and university quantum programs.
The geographic concentration of quantum patents in a few states reflects the importance of proximity to major corporate research laboratories and university quantum computing programs.

Quality Indicators

Figure 10

Quantum Computing Technology Scope Reached 3.6 in 2020, Declining to 2.68 in 2024

Average claims, backward citations, and technology scope for quantum computing patents by year.

Average claims, backward citations, and technology scope for quantum computing patents by year. Technology scope reached 3.6 in 2020 (with earlier years showing higher values on small sample sizes) before declining, suggesting that quantum patents have become more specialized.
Technology scope in quantum patents reached 3.6 in 2020 and has since declined, suggesting that the field is increasingly focusing on more specialized technical challenges rather than broad interdisciplinary exploration.
Figure 11

Quantum Computing Top-Decile Citation Share Reached 45.1% in 2015 and 40.0% in 2020, Consistent With a Frontier Domain

Share of domain patents in the top decile of system-wide forward citations by grant year × CPC section.

Top decile computed relative to all utility patents in the same grant year and primary CPC section. Rising share indicates domain quality outpacing the system; falling share indicates dilution.

Team Size Comparison

Quantum computing patents have generally involved larger inventor teams than non-quantum patents in recent years, though the gap has narrowed to near-zero. The comparison illustrates the capital-intensive, team-based nature of quantum research relative to the broader patent system.

Figure 12

Quantum Patents Average 3.22 Inventors versus 3.18 Non-Quantum in 2024, Near-Convergence

Average inventors per patent for quantum vs. non-quantum utility patents by year.

Average number of inventors per patent for quantum computing versus non-quantum utility patents. The data indicate that quantum patents have generally involved larger teams in recent years, though the gap has narrowed to near-zero by 2023–2025.
Quantum computing patents have generally involved larger teams than non-quantum patents, though the gap has converged in recent years, reflecting the collaborative yet increasingly efficient nature of quantum research.

Assignee Type Distribution

Figure 13

Corporate Assignees Account for 98.8% of Quantum Computing Patents in 2024

Distribution of quantum computing patents by assignee type (corporate, government, individual) over time.

Distribution of quantum computing patent assignees by type over time. Corporate assignees account for over 98% of quantum patents, with government entities and individual inventors making up the remainder.
Corporate assignees overwhelmingly dominate quantum computing patenting, accounting for over 98% of filings. Government entities contribute 1.2% and individual inventors 0.2%.

Quantum Computing Strategies

The leading quantum computing patent holders pursue markedly different hardware and software strategies. Some firms concentrate on superconducting qubit architectures, while others invest in trapped ions, topological approaches, or quantum software and algorithms. A comparison of subfield portfolios across major holders reveals where each organization concentrates its inventive effort and identifies areas of strategic differentiation.

Cross-Domain Diffusion

Although quantum computing remains a relatively young technology domain, its patents increasingly co-occur with CPC codes from other technology areas. Tracking this cross-domain diffusion provides insight into the expanding application space of quantum technologies, from cryptography and materials simulation to optimization and machine learning.

Figure 14

50.5% of Quantum Computing Patents Are Co-Classified With Electricity (H) in 2024, Indicating Deep Hardware Integration

Quantum computing patents co-classified with other CPC sections, measuring cross-domain diffusion.

Percentage of quantum computing patents that also carry CPC codes from each non-quantum section. Rising lines indicate quantum technology diffusing into that sector. The co-occurrence with Electricity (H) reflects quantum hardware's deep ties to electrical engineering, while connections to other sections suggest broadening applications.
The growing co-occurrence of quantum patents with diverse CPC sections suggests that quantum computing is beginning to diffuse beyond pure physics into adjacent application domains, though the pattern remains more concentrated than for established general-purpose technologies such as AI.

Analytical Deep Dives

For metric definitions and cross-domain comparisons, see the ACT 6 Overview.

Figure 15

Top-4 Concentration in Quantum Computing Patents Declined From 76.9% in 2003 to 28.4% by 2025 (Through September)

Share of annual patents held by the top 4 organizations, measuring quantum computing concentration.

CR4 computed as the sum of the top 4 organizations' annual patent counts divided by total quantum patents. The extremely high early concentration reflects the field's origin in a handful of corporate and government research labs. The decline to 28% by 2025 (Through September) indicates broadening participation, though concentration remains among the highest of the ACT 6 domains alongside agricultural technology (33%) and semiconductors (32%).
Quantum computing's high residual concentration (28%) is consistent with the substantial capital requirements for quantum hardware research, which limit participation to well-funded organizations with access to cryogenic facilities and specialized fabrication capabilities.
Figure 16

Quantum Computing Subfield Diversity Increased From 0.78 in 2006 to 0.95 by 2025 (Through September)

Normalized Shannon entropy of subfield distributions, measuring evenness across quantum computing.

Normalized Shannon entropy (H/ln(N)) ranges from 0 (all activity in one subfield) to 1 (perfectly even distribution). The increase from 0.78 to 0.95 indicates a shift from predominantly physical realizations to a balanced distribution across quantum algorithms, error correction, quantum networking, and hybrid classical-quantum systems.
The high entropy by 2025 (Through September) suggests that quantum computing has matured beyond the hardware-only phase into a multi-layered technology stack, with significant inventive activity at the algorithm, software, and application layers.
Figure 17

Quantum Computing 2020s Entrants Average 6.0 Patents per Year, Similar to 2010s Entrants at 5.9

Mean patents per active year for top organizations grouped by decade of first quantum filing.

Mean patents per active year for top quantum organizations grouped by entry decade. Only cohorts with three or more organizations are shown. The 1990s cohort (2 organizations: IBM and MIT) does not meet the minimum threshold and is excluded, though those early entrants averaged 11.0 patents per year. Among qualifying cohorts (2000s, 2010s, 2020s), velocity has remained relatively stable, suggesting that the field's rapid growth reflects breadth of participation rather than intensification by individual firms.
The relatively stable velocity across the 2000s, 2010s, and 2020s cohorts suggests that quantum computing's growth reflects primarily new entrants rather than increased per-firm productivity. The 1990s cohort (2 organizations, excluded for small sample size) had much higher velocity, reflecting the pioneering scale of IBM and MIT.

Having documented the growth of quantum computing in the patent system, the trajectory of this field illustrates how foundational physics research can transition into an engineering discipline with broad industrial potential. The organizational strategies behind quantum patenting are explored further in Assignee Composition, while the relationship between quantum computing and semiconductor innovation is examined in the Semiconductors chapter.

Figure 18

Quantum Filing Peaked at 579 in 2021 While Grants Reached 660 in 2024 — Rapid Growth on a Small Base

Annual patent filings versus grants for quantum computing, showing the field's recent acceleration.

Quantum computing exhibits rapid recent growth in both filings and grants, though from a very small base. The filing-to-grant lag reflects both the technical complexity of quantum patent examination and the rapid expansion of filings after 2017. Grants surpassed the filing peak in 2024, reflecting the processing of the 2019–2021 filing surge.

Data coverage: January 1976 through September 2025. All 2025 figures reflect partial-year data.