[Amidst a sell-off in AI concept stocks, Bitcoin mining companies transitioning to data centers are re-emphasizing their core mining business to reassure investors.] According to Bloomberg, as AI stocks are experiencing a sell-off, some large Bitcoin mining companies that previously transitioned to AI infrastructure are re-emphasizing their core crypto business to appease investors. MARA Holdings CEO Fred Thiel stated in a letter to shareholders that Bitcoin mining remains the core business; Bitdeer Chief Strategy Officer Haris Basit also stressed that the company does not want to rely on any single market cycle. The report points out that after the 2024 Bitcoin halving led to declining profit margins and a surge in demand for AI computing power, providing AI services became a core focus for many mining companies, resulting in billions of dollars in hosting agreements. However, the widening gap between AI capital expenditures and actual revenue, along with public opposition to data centers, has punctured the AI valuation boom.