BIP-110, one of Bitcoin’s most controversial proposals, was designed to reshape how Bitcoin handles on-chain data. After its attempted activation produced a stalled minority chain, the proposal now faces a major credibility test👇
🖥 BIP-110 in a nutshell
BIP-110, originally drafted as BIP-444, is a temporary Bitcoin soft fork designed to place consensus-level limits on arbitrary, non-financial data stored inside Bitcoin transactions.
The proposal primarily authored by pseudonymous developer Dathon Ohm, with early input from Bitcoin developer Luke Dashjr, was marked complete in June 2026.
The proposal would operate for roughly one year, covering approximately 52,416 blocks before automatically expiring.
At its core, BIP-110 targets the growing use of Bitcoin block space for data-heavy applications, including Ordinals inscriptions, BRC-20 tokens and Runes.
What Does It Try to Solve?
Bitcoin blocks have increasingly carried data that is unrelated to transferring BTC. Supporters argue that this creates costs that extend beyond the transaction fee paid by the user.
Key concerns:
🕊️Blockchain storage: Every full node must download and validate block data, while non-pruned nodes may retain it indefinitely.
🕊️ Block-space competition: Large data transactions consume scarce block space that could otherwise be used for monetary transactions.
🕊️ Node accessibility: Growing blockchain requirements can increase the hardware, bandwidth and storage needed to operate a full node, potentially reducing decentralization.
🕊️ Incentive imbalance: Miners receive transaction fees immediately, while the wider network continues carrying the storage and verification burden.
BIP-110 therefore attempts to move restrictions on certain data-heavy transaction structures from relay policy into consensus rules, making them invalid for nodes enforcing the soft fork.
🔄 What Would BIP-110 Change?
The proposal introduces several technical restrictions for transactions created after activation.
🕊️ Most new output scripts would be restricted to 34 bytes, with OP_RETURN outputs permitted up to 83 bytes.
🕊️ Many data pushes and witness stack elements would be capped at 256 bytes.
🕊️ Taproot control blocks would face a roughly 257-byte limit and annexes would become invalid.
🕊️ Undefined witness versions would no longer be spendable under the proposed rules.
Existing UTXOs would generally be grandfathered, meaning previously created coins and most existing inscriptions would remain spendable.
❌ The proposal also does not directly ban Ordinals, Runes or other token protocols. Its approach is to restrict the transaction structures that allow large quantities of arbitrary data to be embedded into Bitcoin.
🤝 Why Backers Support It
BIP-110 supporters argue that Bitcoin's consensus rules should prioritize its monetary function and preserve the ability for ordinary users to operate validating nodes.
Their main arguments are:
🕊️ Lower long-term node costs by limiting the amount of arbitrary data that can enter the blockchain.
🕊️ Protect monetary transactions from competing with large-scale non-financial data applications for block space.
🕊️ Prevent miners from capturing immediate fees while imposing persistent storage costs on the wider node network.
🕊️ Restore stronger limits after Bitcoin Core 30.0 expanded default OP_RETURN relay capacity in 2025.
🕊️ Use a temporary restriction that can expire after roughly one year, giving developers time to evaluate the consequences and design a longer-term solution.
Some supporters also argue that users and node operators should have the ability to enforce their preferred Bitcoin rules directly rather than relying entirely on miner signaling.
🤜 The Controversy
The central disagreement concerns whether Bitcoin consensus should regulate the purpose of transaction data.
Critics argue that Bitcoin should remain neutral toward valid, fee-paying transactions regardless of what information they contain.
Many including Michael Saylor, Adam Back, Jameson Lopp, Samson Mow and Peter Todd have raised several concerns:
🕊️ Consensus precedent: Restricting one legitimate use case could establish a framework for restricting other applications in the future.
🕊️ Effectiveness: Data can potentially be fragmented, disguised or routed through miners willing to include it, creating an ongoing cat-and-mouse game.
🕊️ Chain-split risk: The proposed activation mechanism could cause enforcing nodes to reject blocks accepted by the economic majority.
🕊️ Governance: Critics questioned whether BIP-110 had sufficient technical and economic consensus to justify a consensus-level change.
🕊️Transaction compatibility: Certain unusual Taproot, Miniscript and pre-signed transaction structures could potentially be affected.
The activation mechanism became one of the most contentious elements. BIP-110 used a modified signaling system with a 55% miner threshold and later introduced mandatory signaling. Opposers argued that enforcing the rule without overwhelming miner and economic support could create a competing minority chain.
▶️ So What Happened?
The proposal never gained meaningful support across Bitcoin’s mining ecosystem.
Before mandatory signaling began, only around 51 blocks, or 2.53% of blocks in the relevant difficulty period, signaled support for BIP-110. That was far below its proposed 55% threshold.
The key test came around block 961,632 in early August 2026.
AntPool then mined a block without signaling for BIP-110. The main Bitcoin network accepted the block, but nodes enforcing BIP-110 rejected it, causing those nodes to split onto a separate minority chain.
Roughnecks, operating through OCEAN, mined two blocks on the BIP-110 chain. But with only a tiny share of Bitcoin’s total hashrate, the minority chain quickly stalled.
The outcome highlighted the limits of an approach without broad network support: nodes can enforce different rules, but a consensus change only becomes Bitcoin’s new standard when miners, exchanges, wallets, custodians and users broadly adopt it.
Bottom Line
BIP-110 has effectively failed as a network-wide consensus upgrade, but the underlying block-space debate remains unresolved.
The debate is likely to move back toward policy and relay rules, where miners and node operators can choose how much arbitrary data they relay or include without creating an incompatible consensus rule.
For now, the main chain has rejected the proposed change through economic and mining coordination. The question of how Bitcoin should handle large-scale non-financial data, however, remains firmly open.