A long-running argument inside Bitcoin finally produced a chain split on Saturday, and it was over almost before it began. The breakaway network mined two blocks in roughly eight hours and then stalled, falling dozens of blocks behind the main chain while Bitcoin carried on producing one about every ten minutes.
The split triggered at block 961,632, when nodes running BIP-110 software began rejecting any block that did not signal support for the proposal. A block mined by AntPool without that signal was accepted by the main network and rejected by the BIP-110 nodes. A miner on the Ocean pool produced the alternative that the minority chain then followed.
Why the Fork Stalled
The problem is arithmetic, and the fork cannot easily escape it.
Bitcoin adjusts how hard it is to mine a block only once every 2,016 blocks, roughly a fortnight. The breakaway chain inherited Bitcoin’s current difficulty setting at the moment of the split, but took almost none of Bitcoin’s computing power with it. About 2.53% of recent blocks had signalled for the proposal, far below the 55% needed to activate it without a split.
That leaves a chain trying to solve Bitcoin-sized puzzles with a fraction of Bitcoin’s machinery. Blocks arrive hours apart instead of minutes, and at that rate the fork would need an estimated 350 days to reach the difficulty adjustment that would make mining easier again. Bitcoin will reach its next one in about two weeks.
What BIP-110 Was For, and Who Objected
BIP-110 was a soft-fork proposal to temporarily stop people embedding images, text and other non-financial data inside Bitcoin transactions. Supporters argued the practice, popularised by Ordinals inscriptions, congests the network and pushes up fees for people making ordinary payments, and that hosting arbitrary data creates legal exposure.
Opponents, who turned out to be the large majority, argued that anyone paying for block space has bought the right to use it however they like, and that letting miners and node operators decide which transactions are acceptable erodes the censorship resistance Bitcoin exists to provide. Michael Saylor of Strategy was among the critics, warning that turning a spam dispute into a consensus change sets a dangerous precedent.
Two Numbers Doing Different Jobs
Two figures are now circulating, and they are not measuring the same thing.
The 2.53% describes how many recent blocks had signalled support for BIP-110 before the split. Saylor, posting on X early on Sunday, put it differently, saying about 99.85% of Bitcoin’s hashpower stayed with the main chain and that the BIP-110 branch was already more than 80 blocks behind.
Signalling support and actually mining the minority chain are separate decisions, and some miners who signalled did not follow the fork when it arrived. That is where the gap between roughly 2.5% and roughly 0.15% comes from. Both numbers are accurate and they answer different questions.
The tone afterwards was not conciliatory. Jameson Lopp, co-founder of the Bitcoin security firm Casa, said on X that he would not be welcoming back or unblocking BIP-110 supporters, accusing them of falling for propaganda and of harassing people who have spent their careers working on Bitcoin.
The Risk for Anyone Holding Forked Coins
There is a practical hazard here that matters more to ordinary holders than any of the politics.
Because both chains accept identical transactions, a sale made on the minority chain can be replayed on Bitcoin. In plain terms, someone selling forked coins could find the same transaction executed against their real BTC, handing a buyer genuine Bitcoin out of the same balance. Anyone tempted to extract value from the split should understand that risk before touching either chain.
The mandatory signalling window closes at block 963,647, a mark the minority chain has no realistic path to reaching. Bitcoin itself was trading around $65,168 on Sunday evening, up 0.1% on the day, which is roughly the market’s verdict on how close any of this ever came to mattering.
