Some of the biggest bitcoin exchanges, including Bitfinex, Bitstamp and Kraken, as well as Poloniex, the biggest altcoin exchange, will not follow the longest chain. They will, instead, list Bitcoin Unlimited as BTU while Bitcoin Core will remain as BTC, regardless of which has the majority hashrate or, presumably, price. They state:
“Since it appears likely we may see a hardfork initiated by the Bitcoin Unlimited project, we have decided to designate the Bitcoin Unlimited fork as BTU (or XBU). The Bitcoin Core implementation will continue to trade as BTC (or XBT) and all exchanges will process deposits and withdrawals in BTC even if the BTU chain has more hashing power. Some exchanges intend to list BTU and all of us will try to take steps to preserve and enable access to customers’ BTU.”
The exchanges state the decision was not made to pass any judgment, but they believe a hardfork needs miners and users consensus which they state has not been achieved. Moreover, the Bitcoin Unlimited chain will be listed as BTU regardless of any factor for technical reasons, they say:
“In the case of a Bitcoin hardfork, we cannot suspend operations and wait for a winner to emerge. Many of our platforms allow leveraged trading that requires markets to operate continuously. Due to operational requirements alone we are compelled to label an incompatible fork as a new asset.”
This is an unprecedented decision and contrary to all previous decisions by exchanges when currencies have split. In the case of eth, for example, despite it creating a new chain through a new client, the coin with most community support, ethereum, retained the eth ticker while the minority were listed as ETC.
The decision, further, in effect, disregards Nakamoto’s consensus and fully undermines miner’s role in the upgrade process, giving Bitcoin Core developers, who lack binding monetary incentives, the upper hand.
Moreover, the co-ordination of all these exchanges in what appears to be a private meeting with no independent observers seems concerning to some bitcoin users, including strong Bitcoin Core supporters.