looks like a classic mining control slow sell off to me.
this means they have real bag holders to sell to.
That's the downside to PoW. It's one thing when people were hobby mining in 2010. In 2014 - Professional miners dominate it now and they're lmost never long term holders. They have overhead bills (electricity / bandwidth / hardware) and they tend to dump at the first opportunity and then move onto the next PoW coin.
PoW is so laughable but what's more funny is people still throw their money at PoW coins