Marathon Digital: The Largest Listed Bitcoin Miner

Short answer: Marathon Digital has been called MARA Holdings since 2024 and is one of the largest listed bitcoin miners in the world. At the end of September 2026, MARA had 71.2 EH/s of computing power connected and held 34’012 BTC, more than any other miner. For a long time the company kept every bitcoin it mined and bought more with convertible notes. In 2026 it abandoned that course and sold about 27’000 BTC.

Many investors buy miner stocks as "bitcoin with leverage". That is only partly true. Using MARA as the example, this article shows how a large miner makes money, what a bitcoin costs it and why its stock moves differently from bitcoin. How mining works technically is explained in Bitcoin mining explained.

What is MARA Holdings?

MARA is based in Florida and listed on Nasdaq under the ticker MARA. The company started out as Marathon Patent Group, a business that licensed patents. From 2017 it moved into bitcoin mining, and in 2021 it renamed itself Marathon Digital Holdings. The current name, MARA Holdings, followed on August 29, 2024.

Today MARA describes itself as an energy and computing infrastructure company. According to its quarterly report, bitcoin mining remains "the foundation"; alongside it, MARA is building data centres for artificial intelligence and buying power plants. At the end of September 2026 the portfolio covered about 1.9 gigawatts of capacity in 19 data centres in North America, Europe, Latin America and the Middle East.

The hashrate is the computing power MARA uses to search for the next block. MARA reports its "energized hashrate", meaning what all connected machines would deliver at full power. In practice, never all machines run at the same time.

How big is MARA in the network?

The whole Bitcoin network had about 936 EH/s in November 2026. On paper, MARA therefore provides a little over 7% of the computing power. In the third quarter of 2026, MARA found 7 blocks a day on average. With about 144 blocks per day, that is almost one block in twenty. MARA runs its own pool for this and, according to its annual report, also uses third-party pools for part of its hashrate. How pools share the reward and why almost every miner belongs to one is covered in How Bitcoin mining pools work.

How many bitcoin does MARA hold?

As of Sep 30, 2026, MARA held 34’012 BTC. That puts the company in fifth place among the listed companies in our overview, behind Strategy, Metaplanet, Twenty One Capital and Strive. Among miners it is clearly ahead: CleanSpark reports 13’530 BTC, Riot Platforms 2’418 BTC (both as of Sep 30, 2026). The direct comparison of those two is in Riot Platforms vs. CleanSpark.

Of the 34’012 BTC, 19’260 BTC were tied up in MARA's "digital asset management". That means lent out, pledged as collateral or used in trading arrangements. These bitcoin are not simply sitting in the company wallet.

The drop in the first quarter of 2026 is not a measuring error. In the first nine months of 2026, MARA sold about 26’984 BTC and mined 6’916 BTC over the same period. Among other things, it used the money to buy back about $1 billion of convertible notes and to repay loans.

Keep, buy, sell: MARA's bitcoin strategy

MARA has changed its stance on bitcoin several times. This matters for investors, because the holdings are only worth as much as the rule by which the company manages them.

2021: the first purchase

In January 2021, Marathon bought about 4’813 BTC for about $150 million. That made it one of the first companies after Strategy to hold bitcoin deliberately as a reserve. What such companies have in common and how to value them is covered in Bitcoin treasury companies explained.

2024: keep everything and buy more

In the third quarter of 2024, MARA adopted a full "HODL" strategy: every mined bitcoin stays on the balance sheet, plus purchases on the market. The money came mainly from convertible notes. In total, MARA raised about $2.2 billion in 2024, $1.9 billion of it at 0% interest. With it the company bought exactly 22’065 BTC in 2024 at an average price of $87’205 and mined another 9’430 BTC.

How a convertible note works

A convertible note is a loan that the lenders can later exchange for shares. Because they get this option, they ask for little or no interest. If the share rises above the so-called conversion price, they convert and MARA does not have to pay anything back, but it issues new shares. If the share stays below it, the lenders want their money back at maturity, in cash.

Together that is about $2.3 billion. The last column matters: on those dates the holders can demand their money back early. If the share is below the conversion price then, MARA has to pay. For the 2032 note this applies only in that case.

2025 and 2026: selling again

In the second half of 2025, MARA allowed itself to sell mined bitcoin again. In 2026 the company extended this to its entire holdings. The quarterly report now says that MARA may hold bitcoin long term, but may also sell it or buy opportunistically, depending on the market and its capital needs. In August 2026, MARA also took out a $750 million loan secured by 18’750 BTC and repaid it in full after the quarter ended.

For you this means: at MARA, management decides whether the bitcoin holdings grow or shrink. If you hold bitcoin directly, you decide yourself.

What does a mined bitcoin cost MARA?

A miner's biggest bill is electricity. MARA reports its own metric for this: electricity cost per bitcoin at its own sites. It was $29’084 in 2024, $38’956 in 2025 and $39’674 in the third quarter of 2026.

But electricity is not everything. MARA also pays third-party operators for hosting, pays for maintenance and staff, and has to keep replacing old machines. A rough calculation with the figures from the quarterly report shows how this adds up.

This is our own back-of-the-envelope calculation. Depreciation and overhead also concern the AI business, not only mining. Still, it shows the basic problem: a miner needs a bitcoin price well above its electricity costs to make a profit over time.

Why small price changes have a big effect

Because the costs are largely fixed, every price change hits the margin in full. If the bitcoin price in the example above falls by 10%, revenue per bitcoin drops from $71’688 to about $64’500. Direct costs stay at $63’700. The margin shrinks from about $8’000 to under $900, a fall of almost 90%. If the price rises, the lever works just as strongly upwards. This is the main reason why miner stocks swing more than bitcoin.

The risks of a miner

Halving: half as much for the same effort

The halving is the biggest predictable risk for miners. After the April 2024 halving, MARA's output fell even though the company raised its hashrate from 53.2 to 66.4 EH/s: it mined 9’430 BTC in 2024 and only 8’799 BTC in 2025. Over the same period, the electricity cost per bitcoin rose by a third. How the halving works is explained in The Bitcoin halving explained simply.

The chart shows why the problem grows: each halving cuts the new supply in half. In the long run, fees have to carry a growing share of miner income. At MARA they made up only 0.7% of mining revenue in the third quarter of 2026.

Dilution: more shares, less bitcoin per share

In March 2021, MARA had 98.8 million shares. At the end of October 2026 it had 387.4 million, almost four times as many. For shareholders, what counts is not the company's holdings but how much of it falls on one share.

Miner stock or holding bitcoin: the difference

With a MARA share you own a stake in a company, not in bitcoin. The bitcoin holdings are only one part of it. On top come machines, sites, power plants, debt and the AI business.

A miner stock can make sense if you deliberately want to bet on a company: on cheap power, efficient machines and good management. As a substitute for bitcoin it does not work. The general comparison between treasury stocks and real bitcoin is in Bitcoin stock or buy bitcoin?.