Crypto currency transfer from one person to another

This year two friends of mine and I bought crypto currency under one friend's coin base account.  We agree to buy "X" amount and we each split the cost 3 ways.  We gave that friend the money and he purchased the crypto.  In April, that crypto took off in value and we decided it would be best if we transferred our stake to our own individual accounts so we could manage it how we choose.   We completed that transfer and everything was fine.  

 

Now he is telling me he is liable for taxes on the full amount and that I need to send him money to pay my share of the taxes.  Based on the research I have done, his understanding is incorrect.  I do not think he is trying to screw me over, but I do think he is not understanding his tax implications correctly.  Who is correct here?  I need some help.