Shares of cryptocurrency miner Marathon Digital (NASDAQ:MARA) drop nearly 30% on Monday following a $500M debt offering to buy more Bitcoin (BTC-USD), in addition to receiving a subpoena from the Securities and Exchange Commission. Of course, the debt offering implies share price dilution as the supply of capital increases. Bitcoin (BTC-USD) wasn't much of any help to MARA's stock performance as the digital token also slips 0.8% in the past 24 hours. Still, MARA's total return outpaces Bitcoin (BTC-USD) by more than 10-fold in the past year, as seen in the chart below. Recall Marathon Digital (MARA) shares also fell after missing crypto mining revenue expectations.