Key Points
Arqit Quantum is a promising developer of technology that protects against cyberattacks from quantum computers.
Although quantum computers don’t present a cybersecurity threat yet, it could be only a matter of time.
Arqit could have a huge addressable market if this quantum computing threat materializes in the next few years.
Every now and then, a new technology meets its moment. That’s arguably happening with quantum computing.
Over the last three months, several quantum computing stocks have skyrocketed. IonQ’s share price is up more than 40%. Rigetti Computing has soared more than 60%. The aptly named Quantum Computing has seen its share price more than double. And D-Wave Quantum is the biggest winner, with its stock skyrocketing more than 140%.
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Another largely underrated quantum computing stock has also taken off in recent months. And it could deliver huge gains by 2030 with a little luck.
Image source: Getty Images.
A promising “anti-quantum computing” stock
The stock I’m referring to is Arqit Quantum(NASDAQ: ARQQ). You might say that Arqit is more of an “anti-quantum computing” stock than it is a quantum computing stock.
Arqit has developed technology that can protect any networked device or data against cyberattacks from quantum computers. Its flagship product, Arqit SKA-Platform, uses symmetric key agreement (SKA). This cryptographic approach allows two or more parties to share a secret key used for encryption and decryption without sending the key over an unsecured channel.
SKA-Platform depends on a proprietary version of a process called replicated entropy, where identical sets of random numbers are delivered securely to data centers. The product also features a lightweight software agent that can be downloaded onto any device. It supposedly would take even the fastest quantum computer millions of years to break the symmetric encryption keys created by SKA-Platform.
Arqit and its technology have already garnered a lot of praise. The company was recognized for its innovation in 2023 at the Institution of Engineering and Technology awards. It has also been named the Cyber Security Awards’ Cyber Security Software Company of the Year and won the Innovation in Cyber Award at the National Cyber Awards in the United Kingdom.
“Q day is coming”
Quantum computers don’t present a cybersecurity threat — yet. However, to use Arqit’s words, “Q day is coming.” It’s only a matter of time before a large-scale quantum computer is developed that puts the entire public key infrastructure (PKI) encryption framework in jeopardy.
Over the last 12 months, several quantum computing leaders have achieved major milestones. The more progress they make, the greater the interest is likely to be for Arqit’s technology.
That interest is already picking up. The company has inked contracts with a major telecommunications network operator and the U.S. Department of Defense. It expects to land more deals in the coming months.
Arqit thinks that its SKA-Platform could be used on every cloud and networked device in the world. The company also believes that its product is the only one that can create encryption keys to protect against quantum computer cyberattacks using a cloud platform at a large scale and low cost.
As you might imagine, this creates a massive opportunity for Arqit if it’s right. Gartner estimates that the global cybersecurity market will reach $294 billion by 2028. If current encryption methods are rendered obsolete by quantum computers, Arqit should be able to target virtually all of this market.
High risk, potentially high reward
That’s an exciting total addressable market for a company with a market cap hovering around $450 million. But while Arqit Quantum offers potential high rewards for investors, it also comes with high risk.
The company’s future hinges on the development of quantum computers that present a huge cybersecurity threat. Arqit has no control over whether this will happen and, if it does, when it will happen.
In the meantime, expenses are increasing while revenue is meager (only $67,000 in the first half of fiscal year 2025). Arqit is on track to burn through its cash position of $24.8 million as of March 31, 2025, by early next year.
The company can tap its at-the-market equity offering program to raise up to $75 million. However, that means issuing new shares — and diluting the value of existing shares.
Still, it’s quite possible that Q day will arrive within the next few years. If it does, Arqit’s stock could skyrocket. And this anti-quantum computing stock could truly meet its moment.
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Keith Speights has no position in any of the stocks mentioned. The Motley Fool recommends Gartner. The Motley Fool has a disclosure policy.