There are 3 coins using the ticker symbol ACC.
Accelerator Network (ACC), AdCoin (ACC) and ACChain (ACC).
Each of them is listed on 2 different exchanges (6 in total).
If Accelerator Network (ACC) wants to get listed on CoinExchange, it can't do that under the ticker ACC since AdCoin (ACC) is already listed there.
Yes, this is really confusing. I am tracking my ACC position in a cointracking tool and I had to edit the ticker multiple times. Really annoying...