This makes perfect sense! I was wondering why the price was being held back with sell walls. If some whale knows it will be going on Poloniex soon they can buy this coin on Bittrex while holding the price back from spiking. This allows them to continue buying while still paying a low price!

It won't be any surprise to me when this goes on Poloniex and then the price skyrockets making the whale who bought a lot of PIVX on Bittrex a very rich person.