Bitcoin's OP_RETURN Limit Sparks Node Exodus: Is a Split Coming?
Bitcoin's OP_RETURN Debate Heats Up
A contentious decision by Bitcoin Core developers to remove the OP_RETURN data limit has ignited a fierce debate within the Bitcoin community. The move, slated for the upcoming Bitcoin Core 30 upgrade, has been met with strong opposition, drawing comparisons to the block size wars of 2015-2017.
Jimmy Song, a prominent Bitcoin (BTC) developer and advocate, criticized the decision, labeling it a “fiat” mentality. He accused Core developers of dismissing concerns about the implications of removing the 80-byte OP_Return limit, and ignoring significant community pushback.
“The idea that spam is difficult to define, and because of this ambiguity, we shouldn’t be making any distinctions at all in the software, is a time-wasting argument from fiat politics where you pretend not to know the obvious, so the actual debate can never get off the ground — the non-monetary uses of Bitcoin are spam.
“You can argue whether that’s something desirable or not, but saying you can’t define it is a stalling tactic meant to avoid the real argument about actual impact — particularly, the long-term impact of this change,” Song continued.
Node Operators Migrate to Bitcoin Knots
The controversy surrounding the OP_Return limit has triggered a notable shift in the Bitcoin network. Dissatisfied with the Bitcoin Core decision, an increasing number of node operators are migrating to Bitcoin Knots, an alternative Bitcoin node implementation. Bitcoin Knots allows node runners to enforce stricter data size limits, an action that proponents believe is crucial for maintaining Bitcoin's decentralization.
This surge in popularity has seen Bitcoin Knots' share of the network jump from roughly 1% to about 20% in just nine months, a significant increase that underscores the community's concerns.
Decentralization at Stake?
Bitcoin's design and strict data limits have kept the blockchain size relatively manageable. As of 2025, the Bitcoin ledger has accumulated approximately 680 gigabytes of data since its inception in 2009. This manageable size allows individuals to operate nodes on readily available hardware, costing as little as $300, thereby fostering decentralization.
In contrast, some blockchain networks with higher throughput and smart contract functionality demand significantly more data storage and processing power. Running nodes on these networks can cost tens of thousands of dollars, requiring specialized commercial hardware. This creates a barrier to entry, potentially centralizing control in the hands of wealthier entities.
As the Bitcoin community navigates this contentious issue, the long-term implications for the network's decentralization and future development remain uncertain. The current debate echoes the block size wars of the past, raising the possibility of a similar outcome such as a chain split.