If you're the type who views the proverbial glass of water as half empty, you'll probably focus on the fact that shares of D-Wave Quantum (QBTS 2.25%) have plunged close to 50% since early October. On the other hand, if you see the glass of water as half full, you're likely to quickly point out that the stock is still up more than 170% year-to-date.
Pragmatists will look at things differently and wonder if the water in the glass is worth drinking. Is D-Wave Quantum stock a buy? Here are the key bull and bear arguments for this high-profile quantum computing stock.

NYSE: QBTS
Key Data Points
The bull case for D-Wave Quantum
One major argument in favor of D-Wave Quantum is the company's tremendous growth. In the third quarter of 2025, D-Wave's revenue doubled year-over-year. Its revenue in the first three quarters of the year was up 235% compared to the same period in 2024.
The underlying reason for this revenue growth presents another big plus for the company: its technology is already being used to solve real-world challenges. D-Wave uses quantum annealing, a superconducting quantum computing approach that's ideally suited for optimization and probabilistic sampling problems.
A strong customer base is evidence that D-Wave's quantum computing technology isn't merely vaporware. Accenture (ACN +2.34%), BASF (BASFY +1.89%), and Mastercard (MA +1.56%) use D-Wave's systems. So do recently added customers, including pure-play semiconductor foundry SkyWater, Japan Tobacco's (JAPA.Y +1.73%) pharmaceutical division, and Korea Quantum Computing.
It isn't surprising that Fast Company named D-Wave and its Advantage2 quantum computer as a winner in the Computing, Chips, and Foundational Technology category in its 2025 Next Big Things in Tech Awards. Fast Company said that D-Wave is "showing what quantum computing can do right now."
Perhaps the biggest reason to buy D-Wave Quantum stock, though, is the tremendous opportunity for quantum computing. Global consulting firm McKinsey & Company predict that quantum computing could be a $72 billion market by 2035 and a $131 billion market by 2040.
Image source: Getty Images.
The bear case against D-Wave Quantum
Now, let's look at the bear arguments against investing in D-Wave Quantum. The flipside of the company's impressive revenue growth is that its valuation has also increased to a nosebleed level. D-Wave's shares trade at a price-to-sales ratio of 246.
Granted, that's looking at trailing 12-month revenue – and the company's revenue is growing fast. However, there's no guarantee that D-Wave will continue to grow at a fast enough pace to justify such a premium valuation.
The fact that we have to use sales-based valuation metrics highlights another big knock against this stock: D-Wave continues to post substantial net losses. What's worse is that the company's bottom line is going in the wrong direction, with no clear path to profitability.
However, we still haven't addressed the most serious issues with D-Wave Quantum. Although the company's quantum annealing technology is addressing real-world problems today, it's also limited. D-Wave's systems aren't general-purpose quantum computers. Short-seller Kerrisdale Capital even called quantum annealing a "commercial dead end."
Importantly, D-Wave Quantum is competing against multiple rivals whose technology could prove to be superior over the long run. The list includes relatively small players such as IonQ (IONQ +0.68%) and Rigetti Computing (RGTI 1.69%). However, several mega-cap tech giants are also in the mix, including Alphabet's (GOOG +1.62%) (GOOGL +1.53%) Google Quantum AI and Microsoft (MSFT +0.76%).
To buy or not to buy?
If you didn't already know it, you have probably now concluded (correctly, by the way) that D-Wave Quantum is a highly speculative stock. Whether or not you should even consider buying D-Wave depends on your investing style.
Risk-averse investors should absolutely stay away from D-Wave Quantum. There are better and safer alternatives to dip your toes in the waters of quantum computing.
What about aggressive investors willing to take on significant risk? Buying D-Wave Quantum stock could pay off. However, even these investors will probably want to keep their position sizes relatively small rather than bet the farm on D-Wave.