Why Big Four Accounting Firms Are Quietly Buying Quantum Computers
EY has become the first Big Four accounting firm to own a physical quantum computer rather than accessing one through the cloud, installing a photonic system at its Toronto office as part of a broader $3 billion investment in artificial intelligence and emerging technologies. The announcement, made on July 29, 2026, marks a significant shift in how enterprises are approaching quantum computing, yet it also reveals a troubling gap between corporate messaging and technical reality.
What Exactly Did EY Buy?
Here's where the story gets murky. EY confirmed the system is a photonic quantum computer, meaning it uses light particles rather than trapped ions or superconducting circuits to perform calculations. But the company declined to name the vendor, disclose the qubit count, specify the gate fidelity, or provide any other technical specification. Joe Depa, EY's Global Chief Innovation Officer, told Accounting Today that the purchase was "made with more of an eye toward the future than the present," suggesting the machine is primarily a research tool for understanding post-quantum cryptography rather than a production system.
Joe Depa, EY's Global Chief Innovation Officer
Two Canadian photonic quantum companies could have supplied the system. Xanadu Quantum Technologies, headquartered in Toronto and publicly traded since March 2026, builds photonic systems using squeezed light technology. ORCA Computing, a UK-based firm with a Toronto office, manufactures room-temperature photonic systems and has an existing working relationship with EY on renewable energy optimization projects. ORCA has deployed 10 on-premises systems to customers worldwide, giving it more commercial deployment experience than Xanadu. Without confirmation from EY, the identity of the vendor remains unknown.
Can This Machine Actually Do What EY Claims?
EY's press release states the quantum computer will support "optimization, fraud detection, data protection and large-scale risk management." These are ambitious claims for early-stage quantum hardware. If the system is Xanadu's Aurora, the most advanced photonic platform available, it produces 12 physical qubit modes per clock cycle and demonstrated subsystems needed for fault-tolerant photonic computation in a 2025 Nature paper. However, 12 physical qubits cannot perform optimization or fraud detection at commercially relevant scale. Xanadu's roadmap targets 500 logical qubits by 2029 to 2030.
If the system is ORCA's PT-3, the company has demonstrated practical applications in network optimization and cybersecurity partnerships, but these remain proof-of-concept projects rather than production workloads. In either case, the machine in EY's Toronto office is research-grade hardware at the earliest stages of quantum computing's development. Neither vendor's current technology can deliver the classically competitive results on the workloads EY named in its announcement.
Why Are Enterprises Investing in Quantum Now?
The timing reflects a broader strategic calculation. Quantum computing has been "10 years away" for the past two decades, yet progress continues steadily. Large enterprises like EY are making on-premises investments to build internal expertise, establish vendor relationships, and position themselves for the moment when quantum systems become commercially viable. The decision also signals confidence in Canada's quantum ecosystem; EY cited Canada's recognized leadership in quantum computing, access to talent, and proximity to clients as reasons for choosing Toronto.
This mirrors a global trend. Australia is making a billion-dollar bet on PsiQuantum, a US company spun out from Australian quantum research, to build a "useful" quantum computer with a million qubits in Queensland. Australian startups Diraq and Silicon Quantum Computing are being benchmarked by the US Defense Advanced Research Projects Agency (DARPA) to assess their viability as paths to a working quantum computer by 2033.
How Does Quantum Computing Compare to AI Right Now?
Artificial intelligence has captured far more attention and investment than quantum computing in recent years. AI technologies have gained traction at an astonishing pace, while quantum computers remain stuck at the research stage. Some problems once thought to require quantum systems are now being solved with AI, according to technology journalist Gideon Lichfield, who has covered quantum computing for decades.
However, experts see potential for quantum and AI to work together rather than compete. Michelle Simmons, CEO of Silicon Quantum Computing in Sydney, believes quantum processors can be used to train AI systems more efficiently. Her company created a quantum processor called Watermelon to assist in AI machine learning, and customers have been using it for 12 to 18 months. Yet quantum researcher Jacob Biamonte at the Université du Québec cautions that "healthy skepticism" is required for quantum-assisted AI technology, noting it remains a legitimate research direction but not yet an established general capability.
"One important distinction is that AI helping quantum computing is presently more mature than quantum computing helping AI. Classical machine learning is already being used for device calibration, control, circuit optimisation, and error mitigation," explained Jacob Biamonte, quantum researcher at the Université du Québec.
Jacob Biamonte, Quantum Researcher at Université du Québec
What's the European Strategy?
While EY's move reflects enterprise interest in quantum, Europe is taking a more coordinated approach. The European Commission launched a call for tenders to build up to seven AI Gigafactories across Europe, mobilizing roughly 30 billion euros in total investment. But buried in the regulatory framework is a parallel quantum strategy. Council Regulation (EU) 2026/150, which entered into force on January 20, 2026, amended the mandate of the European High Performance Computing Joint Undertaking (EuroHPC JU) to add quantum computing and simulation alongside AI infrastructure.
This creates arguably the broadest institutional framework for classical, AI, and quantum computing of any government in the world. EuroHPC JU now houses three distinct computing tracks within a single governance structure: classical supercomputers, AI Factories and Gigafactories, and an expanding portfolio of quantum computers integrated with supercomputing infrastructure. A new Quantum Technologies Advisory Group sits within EuroHPC JU's governance board, ensuring quantum priorities are debated alongside AI and high-performance computing priorities.
How to Evaluate Quantum Computing Investments
- Vendor Transparency: Demand clear specifications on qubit count, gate fidelity, error rates, and modality before committing to quantum hardware. EY's refusal to disclose these details makes it impossible to assess whether the system matches the stated use cases.
- Timeline Realism: Quantum systems capable of solving real business problems at scale remain years away. Investments should be framed as research and capability-building, not as near-term productivity tools.
- Hybrid Approaches: Rather than replacing classical computing or AI, quantum systems will likely work alongside them for highly specialized problems. Evaluate vendors based on their integration capabilities with existing infrastructure.
- Regulatory Landscape: Post-quantum cryptography readiness is a legitimate near-term use case, as EY acknowledged. Assess whether quantum investments align with your organization's data security and compliance requirements.
The quantum computing industry remains in a state of productive uncertainty. EY's investment signals that enterprises see long-term value in the technology, but the company's vague messaging also reveals how far quantum systems are from delivering on their promises. The real story is not what EY bought, but why it felt compelled to buy it without being able to explain what it does.