Bitcoin split after BIP-110 fails, the new chain stopped after two blocks

Bitcoin mining firm AntPool mined the first non-signalling block, which the rest of the network accepted and BIP-110 nodes rejected, and a miner using Ocean produced the alternative that the breakaway chain followed instead. (A miner is an entity that uses massive computing resources to maintain bitcoin and process its transactions, earning newly issued bitcoin and fees for the work.)

AntPool and Ocean are mining pools, where many operators combine their machines and share the rewards.

The stall has a mechanical cause that is hard to escape. Bitcoin recalculates how difficult mining is every 2,016 blocks, aiming to keep blocks arriving roughly every ten minutes.

The breakaway chain inherited bitcoin’s current setting but has a tiny share of the machines, so its blocks arrive at long intervals. It cannot make mining easier until it completes 2,016 blocks at that pace. The monitor puts that at 350 days away, against 14 days for bitcoin.

Support was never there. Only 2.53% of blocks signalled for BIP-110 over the past two weeks, against the 55% needed to activate it without a split.

That leaves the fork coin in an awkward position for anyone hoping to sell it. Both chains still accept identical transactions, so a signed transaction sending fork coins also works on bitcoin, and a buyer can rebroadcast it there and collect real BTC from the same seller — opening up the chances of a novel attack method that users should keep track of.