Bitcoin's BIP-110 soft fork attempt begins mandatory signaling phase

Aug 7, 2026

The Bitcoin blockchain split into two branches on August 8, 2026, at block 961,632 as nodes enforcing the controversial BIP-110 soft fork began rejecting non-signaling blocks. Written by pseudonymous developer Dathon Ohm, BIP-110 seeks to temporarily restrict non-financial data like Ordinals. Despite having only 2.53% miner support, proponents initiated a user-activated soft fork. The minority chain quickly fell behind the main chain, while developers warned holders of replay attack risks if they move coins.

BIP-110 blockchain split

▪BIP-110 nodes followed an alternative block at height 961,632 produced through the Ocean mining pool by a miner named Roughnecks.
▪The Bitcoin blockchain split into two branches on Saturday, August 8, 2026, at block 961,632 when nodes running BIP-110 began rejecting blocks that did not signal support for the proposal.
▪AntPool mined the first block at height 961,632 without the BIP-110 signal, which was accepted by the main network but rejected by BIP-110 nodes.
▪The minority BIP-110 branch fell behind the dominant main chain quickly after the split, reaching only block 961,633 while the main chain had reached block 961,640 as of Saturday evening.

User-activated soft fork mechanism

▪Public miner signaling for BIP-110 reached only 2.53% (51 of 2,016 blocks) prior to the split, far below the 55% threshold required for ordinary activation.
▪BIP-110's deployment schedule sets blocks 961,632 through 963,647 as a mandatory-signaling window, with transaction restrictions scheduled to take effect at block 965,664.
▪BIP-110 is designed as a user-activated soft fork (UASF) that relies on node operators to enforce new rules from a predetermined block height regardless of miner support.
▪Bitcoin developer Chris Guida rebased preliminary code on August 1, 2026, for a proof-of-work change as a contingency if miners opposed BIP-110.

Replay attack risk

▪Developer Kevin Loaec warned that the safest course for non-experts is to avoid moving or selling coins during the split because BIP-110 lacks built-in replay protection until at least early September.
▪Selling duplicate coins from the BIP-110 fork poses a replay attack risk where transactions could be copied and executed on the main chain, draining the seller's real bitcoin.

BIP-110 technical restrictions

▪BIP-110 was written by pseudonymous developer Dathon Ohm to temporarily restrict how much non-payment data, such as Ordinals and Runes, can be stored on the Bitcoin blockchain.
▪The proposed BIP-110 rules would restrict certain data pushes and witness elements to 256 bytes and temporarily limit several Taproot features to discourage inscriptions.
▪BIP-110 proposes temporary consensus restrictions lasting about one year that would limit most new output scripts to 34 bytes and cap OP_RETURN outputs at 83 bytes.

Bitcoin governance debate

▪Prominent Bitcoin figures Michael Saylor and Adam Back voiced their opposition to BIP-110, arguing that the network's fee market should determine block space use.
▪BIP-110's author Dathon Ohm advised miners to upgrade to Bitcoin Knots to enforce the rules, warning that running Bitcoin Core would become insecure.
▪BIP-110 supporters, including Ocean CTO Luke Dashjr, argue that permanent non-financial data storage burdens node operators and competes with monetary transactions.