A bitcoin miner chose not to back BIP-110 on Sunday, using a tool from its own mining pool that let it decide what went into the block rather than leaving that to the pool.

Simple Mining said it produced block 961,634 on the main chain, two blocks past the point where BIP-110 supporters broke away.

"Hashrate is a vote you cannot fake, and we decided the proposal wasn't worth following," Simple Mining wrote on X.

The choice is notable because Ocean, the pool it mines with, had switched miners to signal for BIP-110 by default in July and accounted for nearly all of the proposal's small amount of mining support before the split.

BIP-110, short for Bitcoin Improvement Proposal-110, is a move to stop people storing pictures, text and other non-financial data inside bitcoin transactions for a year.

Simple Mining could go the other way because it was using DATUM, an Ocean protocol that gives individual miners control over the blocks they produce.

Mining pools normally combine computing power from many operators so they can find blocks more regularly and share the rewards. The pool usually decides which transactions go into those blocks and what software signals they carry.

DATUM moves that decision back to the individual miner. An operator can build its own block using its own bitcoin software while still contributing computing power to Ocean and sharing in the pool's payouts.

Simple Mining used that control to leave the BIP-110 signal out of block 961,634.

"We chose not to signal and the chain extended on our block," the company said.

That also explains why Ocean has appeared on both sides of the weekend split.

A miner using Ocean produced the first block accepted by the BIP-110 branch on Saturday, according to fork tracker Mempool. Simple Mining then used the same pool and made the opposite choice, producing a block for the dominant bitcoin chain.

Computers running BIP-110 software began rejecting blocks that did not carry its signal at block 961,632, after miner support peaked at about 2.6%, far below the 55% the proposal needed.

The minority branch has struggled since. It produced blocks 961,632 and 961,633 before stalling, while bitcoin kept producing blocks roughly every ten minutes.

By Monday a live monitor showed the main chain at 961,725, putting the BIP-110 branch more than 200 blocks behind.