Fidelity CEO Abby Johnson surprised a tech conference this spring by revealing the brokerage giant didn’t just study cryptocurrency. It was also mining the digital assets—and making money while doing so.
It turns out Fidelity has been at this for three years, using its own computers to harvest the digital currencies bitcoin and Ethereum, which today trade for around $4,300 and $300 respectively.
Hadley Stern of Fidelity Labs tells Fortune that the U.S. based mining operation is very modest, however, and the undisclosed profits—CEO Johnson reportedly told the conference the mining “is actually making a lot of money”—are mostly the result of cryptocurrencies’ dramatic rise in value. (Bitcoin traded as low as $200 in early 2015, while the newer Ethereum was just $8 at the start of this year.)
Those profits are nice, of course, but for Fidelity they are not the point. Stern says the real purpose of the mining is to learn about the burgeoning cryptocurrency market.
“Think of it as an experiment. The real reason we began mining, and still do, is to learn how the network works, how consensus works, how difficulty levels work,” says Stern, referring to aspects of the mining process, which involves a network of computers competing to solve complex math problems.
Stern adds that Fidelity’s mining project is not sophisticated compared to professional operations, which involve companies, most of them in China, connecting giant rooms of specialized computers to cheap sources of electricity. But he says Fidelity continues to learn valuable lessons, including about recent campaigns by miners to create so-called “forks” in blockchains, which serve as an immutable record of all cryptocurrency transactions. (The most famous fork occurred this summer when some miners created a rival to bitcoin called “Bitcoin cash.”)
The lessons Fidelity (fnfv) is learning could give it a valuable advantage at a time when other big financial institutions are dipping their toes into the world of cryptocurrencies, which are together worth well over $100 billion today.
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In the last month, J.P. Morgan (jpm) has begun handling customer orders for bitcoin-related financial instruments, while Goldman Sachs (gs) has stoked rumors it might open a trading desk dedicated to digital currencies.
Fidelity’s mining operations aren’t the only way the company is gaining insights into cryptocurrency. This summer, the brokerage entered an arrangement with Coinbase, a popular San Francisco-based exchange, to let customers view the value of their digital currency alongside stocks and others assets on their Fidelity homepage. The Coinbase tie-up is a convenience for customers, but also lets Fidelity gain insight into how many how investors are interested in cryptocurrency.
Meanwhile, Fidelity has also included bitcoin in a program that helps individuals donate specialized assets, such as fine art, to charity. Stern says the company often conducts interviews with customers who donate bitcoin, in part to learn about their interest in the cryptocurrency.
“It’s another way to assess market demand, get our hands a bit dirty with the technology, and learn what’s going on,” says Stern.
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An earlier version of this story misstated the current price of Ethereum.