Brain Armstrong also said, "It appears the prices of Bitcoin Cash on other exchanges increased in the hours before our announcement". "Factors we considered include developer and community support, security, stability, market price and trading volume".
However, many exchanges, including Coinbase, initially refused to support the innovation, casting doubt on its prospects. From a cursory glance, it looked like someone knew about the Coinbase move in advance, triggered a flurry of trading that led to a spike in price, and took advantage of this for a massive windfall.
Starting at 9 a.m. PST today, GDAX began allowing access to its bitcoin cash market once again, holding it in a post-only mode (in which users could submit asks and bids without having them executed) for the two hours that followed. That meant people who owned bitcoin before the split were eligible to receive an equivalent number of bitcoin cash tokens when the cryptocurrency was created.
In a post on Medium, he elaborated: "We've had a trading policy in place for some time at Coinbase". The announcement was made after the prices of Bitcoin cash jumped up some notches.
Coinbase is one of the largest cryptocurrency exchanges in the world, so when it adds a new coin to its portfolio investors take notice.
Were those bitcoin cash increases driven by insider trading? The policy prohibits employees and contractors from trading on "material non-public information", such as when a new asset will be added to our platform.
Coinbase chief Brian Armstrong stressed in a blog post that there was no evidence of insider trading "at this time", but also promised a zero-tolerance approach. While there's "no indication of any wrongdoing at this time", he said that "we will be conducting an investigation".
Despite that, according to crypto tracking website coinmarketcap.com, the total global market capitalisation of cryptocurrencies has now passed $600 billion.