Bitcoin chain split stalls BIP-110 fork

TLDR

Bitcoin briefly split into two chains when the BIP-110 anti spam fork activated, but the minority chain stalled after two blocks and now looks unlikely to succeed.

1. BIP-110 enforced stricter rules on non financial data, creating a minority chain that diverged from the main Bitcoin network at block 961,632.
2. The enforcing chain inherited Bitcoins high difficulty with only about 2 to 3 percent miner support, so it mined just two blocks before effectively freezing.
3. Replay risks and governance tensions remain, but for now economic activity and hashpower are overwhelmingly staying on the main Bitcoin chain.

Deep Dive

1. What Triggered The Split

BIP-110 is a proposed temporary soft fork that would restrict certain uses of arbitrary data in Bitcoin transactions, targeting things like Ordinals inscriptions and other large payloads to reduce perceived spam and legal risk.

When BIP-110 entered its mandatory signaling window at block 961,632, nodes enforcing the proposal started rejecting blocks that did not signal support via version bit 4. That caused a chain split, with an enforcing minority branch at heights 961,632 and 961,633, and the non enforcing majority chain continuing normally. Reports from multiple outlets confirm the enforcing branch stalled at 961,633 while the main chain advanced dozens of blocks ahead, with only about 51 of the prior 2,016 blocks (2.53 percent) having signaled support for BIP-110.

2. Why The BIP-110 Fork Stalled

Because BIP-110 reused Bitcoins existing mining difficulty, but had almost no hashpower, the minority chain faced block times measured in hours rather than minutes. Analyses of the split show the enforcing chain inherited a difficulty target around 127 trillion with only roughly 0 to 2.6 percent miner backing, making progress extremely slow and delaying any difficulty adjustment.

The Roughnecks mining group, using the Ocean pool, produced the only two minority blocks before announcing it would stop BIP-110 mining, and Oceans hashrate collapsed. Supporters have begun debating a proof of work algorithm change to fire Bitcoin miners and revive the stalled chain, but no algorithm, activation height, or consensus change has been approved yet. Articles on the stalled minority chain and proposed PoW reset make clear that the fork currently has negligible practical viability.

3. Risks And What To Watch Next

Because BIP-110 does not introduce built in replay protection, a transaction crafted on one chain can often be valid on the other. That creates replay risk for coins that existed before the split, although in practice the risk depends on whether exchanges and wallets support the minority chain at all.

On the governance side, the episode is intensifying disputes around BIP editors and how consensus changes should be coordinated, with some contributors publicly questioning Luke Dashjrs role and the process that led to BIP-110. The next key signals are whether any large miners or venues begin supporting the enforcing chain, whether a PoW change is seriously scheduled, and whether replay protections or explicit ignore BIP-110 guidance emerge from major wallet and exchange providers.

Conclusion

The BIP-110 chain split shows that attempting to change Bitcoins consensus rules without broad miner and economic support results in a stalled minority fork rather than a new dominant network.

Hashpower, liquidity, and infrastructure remain concentrated on the main Bitcoin chain, while the enforcing branch has frozen and is debating drastic measures like a PoW reset. The episode reinforces that in Bitcoin, practical consensus is enforced by sustained computing power and market adoption, not just by formal proposals.