Early Bitcoin developer Peter Todd (피터 토드) has brought back into focus a debate over Bitcoin's 21 million supply cap and its long-term security structure.

On Aug. 18, local time, blockchain outlet CryptoSlate reported the key issue is whether proof-of-work security can be adequately supported by transaction fees alone as block subsidies keep shrinking through halvings.

The debate grew after parts of Todd's remarks spread on social media. Todd has not argued that Bitcoin's supply cap should be abolished immediately. He presented tail emission as a long-term task at the Bitcoin++ Toronto event on July 23. Tail emission continues small-scale issuance even after new issuance ends, and in that case Bitcoin's total supply would exceed 21 million.

Bitcoin miners receive block rewards that combine newly issued coins and transaction fees. The problem is that under the protocol, subsidies are cut in half every 210,000 blocks, or about every 4 years. Over time, the fee share must rise, but Todd said it has not been confirmed whether stable and sufficient revenue can keep being generated solely by demand for block space.

He said issuance of about 1 percent a year could be excessive. He added that a lower issuance rate could provide incentives for miners to keep operating without imposing a large economic burden. He did not present a Bitcoin Improvement Proposal (BIP) or a Bitcoin Core pull request, nor a specific activation plan or adoption method.

Even current figures show a wide gap between transaction fees and mining subsidies. Daily transaction-fee revenue earned by miners on April 8, 2026 was 2.443 BTC, far below the roughly 450 BTC in mining subsidies on the same day. Fees accounted for about 0.54 percent of total mining revenue. The figures are not enough to conclude anything about the long-term revenue structure, but it is clear that transaction fees make up a very low share of current mining rewards.

Reaction within the Bitcoin camp was largely negative. Analyst Dan Held called the idea a "bad idea." He revived his view that investors trust a monetary system on the assumption of predictable rules. He argued that trust that the rules will not change even in uncomfortable situations matters more than the absolute number of the supply cap.

Analyst Giacomo Zucco offered a different view. He said a low level of tail emission itself might not immediately bring down Bitcoin. He warned, however, that arbitrarily changing an already established economic structure could instead become a "threat to Bitcoin's viability."

Industry influencer Hodlonaut said the social defense line that protects the supply cap could weaken. He warned that if Bitcoin's spirit and culture gradually weaken, the community's resistance to maintaining the cap could also fall.

Todd also acknowledges that actually changing the supply rules is not simple. In a public Q&A in 2022, he said the shift to transaction fees as the dominant security budget would be a major change with little precedent in other proof-of-work cryptocurrencies. At the same time, he said raising the supply cap for tail emission could require a disruptive hard fork, and the damage from that process could be greater than the problem it aims to solve.

The actual process for changes is also difficult. The 210,000-block halving rule remains in the Bitcoin Core mainnet parameters. Developers can release alternative code, but they cannot make existing nodes automatically accept new issuance rules. Operators and other network participants must choose software that applies those rules.

As a result, the debate is far from a stage that would lead to an immediate protocol change. Todd has effectively raised again the question of whether Bitcoin's long-term security budget should be left to fees alone or whether low-level perpetual issuance should be considered. Even so, the article said that whichever direction is taken, changes to the supply rules are unlikely to become reality without a concrete proposal and broad support across the network.

JUST IN: CORE DEVELOPER PETER TODD JUST SAID #BITCOIN SHOULD ELIMINATE THE 21,000,000 SUPPLY LIMIT "IF BTC HAD TAIL EMISSIONS TO BEGIN WITH, NO ONE WOULD CARE" "ECONOMICALLY, IT'S SIMILAR TO GOLD" "WE HAVE THIS TYPE OF SYSTEM THAT SEEMS TO WORK, BUT WE KEEP MARCHING TO A KIND… pic.twitter.com/l6HJFnVkjT