Bitcoin's BIP-110-enforcing branch produced just two blocks before stalling at block 961,633 on Sunday. The non-enforcing chain kept moving and reached block 961,721, pushing the gap to 88 bl
Bitcoin's BIP-110-enforcing branch produced just two blocks before stalling at block 961,633 on Sunday. The non-enforcing chain kept moving and reached block 961,721, pushing the gap to 88 blocks. The data comes from the BIP-110 monitor, last updated at 10:19 am UTC, which showed the branch's newest block was already 12 hours old.
Only one identified group has mined on the enforcing side so far. Ocean records show a pseudonymous outfit called Roughnecks produced the branch's first two blocks using Ocean's DATUM mining protocol. No other pool has followed.
BIP-110, also called the Reduced Data Temporary Softfork, is a one-year soft fork proposal that limits how much non-financial data can sit inside Bitcoin transactions. It restores an 83-byte cap on OP_RETURN outputs, limits most new transaction outputs to 34 bytes, caps certain witness elements at 256 bytes, and restricts several Taproot features that inscription and Ordinals activity relies on. Existing unspent outputs created before activation are grandfathered in and stay spendable.
The proposal's backers argue that arbitrary data stored in transactions functions as spam. A miner collects a one-time fee, while every node on the network stores that data permanently. Supporters, including figures tied to the Bitcoin Knots node implementation, say the rules would push Bitcoin back toward strictly monetary use.
The current fight traces back to October 2025, when Bitcoin Core version 30 changed a default relay setting for OP_RETURN, raising the limit from 83 bytes to 100,000 bytes. That change let far more arbitrary data pass through node relay policy by default. Many Bitcoiners saw it as opening the door wider for inscriptions, Ordinals, and token-style data rather than closing it.
The backlash gave momentum to Bitcoin Knots, an alternative node implementation that kept the tighter 83-byte standard. Figures behind Knots then wrote BIP-110 as a consensus-level answer, moving the data limits out of relay policy and into rules that no single software release could reverse.
BIP-110 needs 55% of blocks to signal support within a 2,016-block period to lock in voluntarily. That threshold was never close. Signaling hovered near 1% to 2.6% through most of the run-up, even after Ocean began signaling by default for its pool.
With voluntary lock-in out of reach, the proposal moved to its fallback: mandatory signaling. That window opened at block 961,632 on Saturday and runs through block 963,647. During this period, nodes running BIP-110 reject any block that does not set version bit 4, while regular Bitcoin nodes keep accepting both signaling and non-signaling blocks. In the 2,016 blocks before mandatory signaling began, only 51 blocks, or 2.53%, had signaled support.
This mechanism is what created Sunday's split. One small mining group chose to build blocks that satisfy BIP-110 nodes. The overwhelming majority of hashpower kept mining under ordinary rules, so the two chains now hold different histories from block 961,633 onward.
The enforcing branch faces a mechanical obstacle on top of the support problem. Bitcoin's difficulty adjusts every 2,016 blocks based on how fast the prior period was mined. The enforcing chain inherited full network difficulty, calibrated for the entire hashrate of ordinary Bitcoin mining, not for the fraction of hashpower actually working on it.
That mismatch explains the pace. Two blocks arrived, then nothing for roughly 12 hours. The branch cannot adjust its own difficulty downward until it completes the full 2,016-block window, so progress stays slow unless meaningfully more hashpower joins it. If support does not grow, the enforcing chain risks falling further behind rather than catching up.
BIP-110 has drawn public criticism from some of the most prominent names in the industry. Strategy executive chairman Michael Saylor said he agrees with the goal of reducing spam but argued the proposal's method threatens Bitcoin's neutral, predictable rule set and its consensus process. He warned that changing consensus rules to invalidate certain fee-paying transactions sets a dangerous precedent, regardless of intent.
Blockstream CEO Adam Back raised a related concern. He said the change could damage Bitcoin's credibility as a system resistant to arbitrary rule changes, and warned it could make some existing unspent transaction outputs unspendable under the new restrictions.
Other developers have criticized how the debate unfolded rather than the technical substance itself, pointing to friction around the original Core v30 OP_RETURN change as an accelerant that turned a policy disagreement into a governance fight.
The mandatory signaling window closes at block 963,647, expected within days given typical block timing. If the enforcing branch cannot attract more hashpower before then, its chain stays thin and vulnerable to reorganization once mandatory signaling ends and network rules realign. Miners on the branch bear the cost of that risk directly, since any blocks they produce could become orphaned if the fork does not hold.
For now, the numbers tell a plain story. One pseudonymous group is mining an enforcing chain that the rest of the network is not following. Whether that changes before the signaling window closes will decide if BIP-110 becomes a footnote or the start of a longer split.
