The boom in share price for artificial intelligence (AI) and high-performance computing (HPC) companies since September has delivered extraordinary returns for bitcoin miners expanding into those industries, but the growth comes at a cost.
Bitcoin BTC$108,386.04 has risen just 10% this year, and with the bubble popping in corporate bitcoin treasuries in recent months, the narrative has shifted toward miners transforming their business models. Miners have been increasingly active in the debt markets as they seek to finance ambitious buildouts of their AI and HPC businesses.
According to The MinerMag, their combined debt and convertible note offerings reached record levels in the third quarter with estimates ranging as high as $6 billion. That raises the risk of default, and investors will now be focused on seeing meaningful revenue generation from the pivot.
TerraWulf (WULF), MARA Holdings (MARA) and Cipher (CIFR) together raised billions through convertible bonds during the quarter, while CleanSpark (CLSK) tapped credit lines to bolster their balance sheets.
The momentum has carried into the fourth quarter. TerraWulf launched a $3.2 billion private placement of senior secured notes, reportedly the largest single offering ever by a public miner, according to the The MinerMag. Soon after, IREN (IREN) issued a $1 billion convertible bond and Bitfarms (BITF) announced a $300 million convertible note.
Some of these instruments, such as IREN’s, carry a zero-coupon structure. Others, like TerraWulf’s latest issuance, feature higher costs, with a 7.75% coupon translating to an annual interest expense of approximately $250 million. This far exceeds the company’s 2024 revenue, which totaled just $140 million, according to The Miner Mag.
Is This Time Different?
During the 2022 bear market, when the hashprice collapsed as bitcoin fell 70%, lenders seized machines that had been used as loan collateral, a technique seen when Core Scientific (CORZ) filed for Chapter 11 bankruptcy.
The MinerMag suggests the AI-HPC focus differentiates the current debt-fueled fundraising cycle unique. By pursuing diversified revenues the miner may be able to reduce the risks.
The market is rewarding higher valuations for miners pivoting from pure-play bitcoin operations to AI/HPC businesses. While convertible bonds still result in shareholder dilution, the pivot is also attracting a new investor base.
The CoinShares Bitcoin Mining ETF (WGMI), often seen as a proxy for the broader bitcoin mining sector, is up 160% year-to-date.
Source: https://www.coindesk.com/markets/2025/10/21/debt-fueled-ai-pivot-puts-bitcoin-miners-to-the-test
