MARA, CleanSpark, Riot Drive Record Bitcoin Hashrate Surge in May

Three major public Bitcoin mining companies collectively increased their realized hashrate by 17.9 EH/s in May, marking a 15.5% growth and contributing to the Bitcoin network’s rising difficulty.

MARA (NASDAQ: MARA) reported a record-breaking month in realized hashrate, producing 950 BTC, its highest output since the 2024 halving. This surge was driven by its MARA Pool, which mined 282 Bitcoin blocks and pushed the company’s realized hashrate to 58.1 EH/s, a 30% increase from April’s estimated 44.69 EH/s. CEO Fred Thiel attributed the boost to improved operational uptime and favorable luck in winning bitcoin blocks. Marathon retained all its mined Bitcoin, bringing its total reserves to over 49,000 BTC.

CleanSpark (NASDAQ: CLSK) came second, producing 694 BTC in May, which translates to a realized hashrate of 42.48 EH/s—up 6.1% from April’s 40.02 EH/s. The company said it expects to surpass 50 EH/s in June. Unlike MARA, CleanSpark liquidated 293 BTC, representing about 42.2% of its monthly output.

Riot Platforms (NASDAQ: RIOT), on the other hand, posted a realized hashrate of 32.76 EH/s in May, up 6.6% from April’s 30.73 EH/s. The company sold almost its entire May Bitcoin production, consistent with its ongoing treasury strategy.

Collectively, these three miners increased their combined realized hashrate from 115.44 EH/s in April to 133.34 EH/s in May, an absolute rise of 17.9 EH/s or 15.5%.

This ramp-up coincides with Bitcoin’s network difficulty reaching a new all-time high over the weekend, erasing much of the hashprice gains seen earlier in May. The synchronized ramp-up highlights the competitive dynamics in the industry, as miners strive to maximize output in an evolving market landscape.