The Bitcoin Improvement Proposal (BIP)-110 appeared to stall at the weekend, when the nodes that support the proposal broke away from the main network and produced the chain split people had been warning about — a tiny, stalled one.

The split came Saturday at block 961,632, when the proposal entered its mandatory signaling window. Nodes running BIP-110 software began rejecting any block that failed to signal support through version bit 4. When the first block at that height arrived without the signal, those nodes rejected it and peeled away onto a separate chain.

And it has gone almost nowhere since. 

A pseudonymous mining group called Roughnecks produced both BIP-110 blocks — heights 961,632 and 961,633 — using Ocean’s DATUM protocol, then stopped. By Sunday afternoon the enforcing branch remained stuck at 961,633 while Bitcoin’s dominant chain had advanced to 961,744, a gap of 111 blocks and roughly 17 hours without a new block on the fork.

The support was never there. Only 51 of the 2,016 blocks in the preceding difficulty period signaled for the proposal, about 2.53%, against the 55% threshold needed for voluntary lock-in. Since the mandatory window opened, none of the first 113 blocks on the dominant chain have signaled.

Bitcoin’s difficulty adjustment compounds the problem. The fork inherited the main chain’s difficulty but commands a negligible share of hashpower, and cannot make mining easier until it completes a full 2,016-block period. Estimates of how long that would take range from under a year to decades, depending on the hashrate assumed.

BIP-110, formally the Reduced Data Temporary Softfork, would have capped arbitrary data in transactions for roughly a year, targeting Ordinals inscriptions and oversized OP_RETURN payloads.

Michael Saylor and Blockstream’s Adam Back both opposed it publicly, objecting less to the goal than to an activation method they argued invited exactly this outcome. Saylor wrote Sunday that Bitcoin had worked as designed, putting 99.85% of hashpower on the main chain.

Mining company Ocean, whose team supported the proposal, informed clients that some miners using Ocean’s Stratum templates may have believed they were mining on Bitcoin while their hashrate was directed to the new BIP-110 chain.

The company said it would reimburse miners affected with rewards they would have earned on the non-BIP-110 chain during that window.