The tax situation is interesting. Many believe that you owe taxes as soon as the funds for a bitcon fork are available to you. For someone with bitcoin in a private wallet that's instantly. For someone with bitcoin in an exchange that's whenever the exchange implements the coin or you withdraw to a private wallet.
For example bitcoin cash was forked August 1, 2017 but coinbase didn't implement it until December 19, 2017.
For example bitcoin cash was forked August 1, 2017 but coinbase didn't implement it until December 19, 2017.
https://bitcoin.tax/blog/how-to-tax-bitcoin-cash-bch/