September 2023 was a record month for Bitcoin mining companies. Three major firms - CleanSpark, Riot Blockchain and Marathon Digital Holdings - reported record levels of cryptocurrency production.

- CleanSpark mined 643 BTC, total supply was 2,240 BTC
- Riot Blockchain mined 362 BTC, receiving over $13 million in energy credits
- Marathon Digital Holdings mined 1,242 BTC for a yearly total of 8,610 BTC

These results coincided with reports of a 5-year all-time high in BTC supply on Kraken and a 506.06M hashrate increase in mid-September.