Points of focus

• Zcash co-founder Eli Ben-Sasson questioned Bitcoin’s fixed 21 million supply cap.
• He argued that permanently lost private keys will gradually reduce Bitcoin’s effective circulating supply.
• Ben-Sasson proposed a maximum annual issuance rate of 4% instead of a permanently fixed supply.

A fresh debate over Bitcoin’s (BTC) monetary policy has emerged after Zcash co-founder Eli Ben-Sasson suggested the network should eventually move away from its fixed 21 million coin supply cap and instead allow the supply to grow by up to 4% annually.

In a post on X, Ben-Sasson questioned the long-term logic behind Bitcoin’s hard supply limit, arguing that private keys are continually being lost, permanently removing coins from circulation. Over a sufficiently long period, he said, every private key would eventually be lost, making Bitcoin’s effective circulating supply steadily shrink.

Capping the supply of Bitcoin at 21M doesn't make sense. Beacuse over time, keys will be lost. In fact, as time goes to infinity, all keys will be lost.

I strongly support a clear monetary policy with an absolute upper bound on the # of Bitcoins in the future. Say, fix a max…

— Eli Ben-Sasson | Starknet.io (@EliBenSasson) July 7, 2026

Proposed model with absolute cap

Rather than maintaining a permanently fixed supply, Ben-Sasson proposed retaining an “absolute cap” on monetary expansion by introducing a maximum annual issuance rate. He suggested a model allowing Bitcoin’s supply to increase by up to 4% each year, saying it would better match long-term human population growth while maintaining adequate liquidity within the network.

Bitcoin’s fixed supply of 21 million coins has been one of its defining characteristics since its creation by Satoshi Nakamoto in 2009. Digital scarcity protects Bitcoin from inflation and makes it an attractive store of value compared with government-issued currencies.

Formidable barriers to policy change

Changing Bitcoin’s monetary policy, however, would require overwhelming consensus across Bitcoin’s decentralized ecosystem of developers, miners, node operators, exchanges, and users. Previous proposals to alter Bitcoin’s supply schedule have consistently faced strong opposition from the community, which considers the hard cap fundamental to the asset’s value proposition.

Ben-Sasson’s comments also revived a broader discussion about Bitcoin’s long-term security. Under the current protocol, miner rewards are cut in half approximately every four years, with new Bitcoin issuance expected to end in the year 2140. As block subsidies decline, Bitcoin miners will increasingly depend on transaction fees to secure the network.

Academic focus on fee-based security

The issue has attracted academic attention toward the Bitcoin security model. A research paper published this year argued that a future dominated by transaction fees could create new security challenges for Bitcoin and explored protocol-level changes that could strengthen incentives without abandoning the cryptocurrency’s existing monetary policy.

The debate comes as Zcash itself has remained in the spotlight following the disclosure of a vulnerability in its Orchard shielded pool earlier in 2026. Although developers patched the issue, the incident reignited discussions around the security and long-term sustainability of privacy-focused cryptocurrencies.

Enduring question and prevailing consensus

While Ben-Sasson’s proposal is unlikely to gain traction among Bitcoin developers and supporters, it highlights an enduring question facing the network: Should Bitcoin’s monetary policy remain permanently fixed or evolve to account for the gradual loss of coins and changing economic conditions? For now, the overwhelming consensus within the Bitcoin community remains firmly in favor of preserving the 21 million supply cap.