3.
Why halt trading? If there are not deposits nor withdrawals that should not matter on buying or selling.
Seems suspect to me.
Lower prices in the longer term aren't good for their revenues which are based on percentage fees.
Yup, BitStamp crash protection squad leaps into action !
That and possibly to stop people moving BTC off the exchange via Ripple ...
https://www.cryptocoinsnews.com/wallet-breach-causes-bitcoin-exchange-bitstamp-to-temporarily-suspend-service/
Quite likely.
...
Disagree. I think most rational decision makers in any bitcoin operation, especially an exchange or custodial wallet provider, that was just hacked to the tune of thousands of BTC is entirely correct in suspending *all* business activity. Heck, the first thing I'd do is unplug every internet connection the business has.