Jeremy Grantham, the GMO co-founder who credited both the 2000 Internet crash and the 2008 real estate collapse, called Bitcoin (BTC) a “useless speculative mechanism” and predicted it would decline over the coming decades.
The veteran strategist built his critique around three failures he sees in crypto. Bitcoin earns no returns, has no stable value and fails to become a usable currency in daily life, he argued.
Proof of work, proof of nothing
Grantham was particularly critical of Bitcoin’s proof-of-work design. According to him, the energy spent to validate transactions does not generate any economic benefit for society.
“Proof of wasted work shouldn’t be worth a bucket of hot spit, and it won’t.”
Bitcoin falls short as money and a store of value
Beyond criticizing mining, he said Bitcoin does not function as a practical currency. Regular users do not accept it at the supermarket and serious investors do not settle large transactions with it. Without a functional transaction layer, the asset cannot claim monetary legitimacy, he added.
He also rejected Bitcoin as a store of value. Unlike stocks, it pays no dividends and generates no cash flow. He says that leaves speculators with nothing to anchor a fair price on.
A skeptic with a criminal record
Grantham’s warnings carry weight because of his background. He flagged the dotcom bubble before 2000 and warned of the U.S. housing collapse before 2008. His most recent warning about the AI bubble extended that thesis to U.S. stocks, where he now sees a decline of up to 70%.
However, its timing is not always precise. His call for the epic 2021 bubble in U.S. stocks came early, as markets were climbing ahead of their 2022 correction.
The remarks on Bitcoin come as BTC trades near $60,500, down sharply from its late 2025 high above $126,000. The US spot Bitcoin ETF is seeing outflows of $6.35 billion over 30 days through mid-June, reflecting slowing institutional demand.
Earlier, Coinbase CEO Bitcoin Outlook also flagged AI infrastructure costs as a variable reshaping crypto…
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