They were not hacked. Here is an e-mail I received from them.
Important Update – Network Service Disruptions
This email is to update you on the network service disruptions IC Markets have been experiencing intermittently over the last two weeks.
IC Markets (ICM) servers are hosted by oneZero Financial (OZF) in the Equinix NY4 data center in New York. Since the 5th of October public internet access to our servers and to that of all OZF hosted clients has been disrupted on an intermittent basis, mostly during the European and North American trading sessions.
Initially OZF informed us that the cause of the disruptions were hardware and ISP related. Given the nature of the outages this made complete sense so ICM and OZF acted on this basis and took appropriate measures to fix what was then believed to be the problem. Shortly after ICM communicated this to clients the network went down again. It was at this stage that OZF informed us that the outages were in fact the result of a deliberate denial of service (DDoS) attack against their entire network. We must stress that a DDoS attack is not ‘hacking’, it is an effort bring down a network to stop people from accessing a server.
Before we continue explaining what happened, we have to address the seriousness of the issue and the lack of information flow from IC Markets. At no stage during the DDoS attacks which lasted between 20 minutes to just over 1 hour was any client’s information or trading account compromised. ICM and OZF believe that the attacks occurred purely for the purpose of causing mass disruption to all clients of ICM and OZF. We have been unable to email clients to inform you of the attack until now, after they have stopped, as this may have introduced new risks.
These are extremely special circumstances that we must take full responsibility for and which we must make right with you, our clients. We are committed to ensuring that all affected clients are heard by our support team and management, and reimbursements are made where appropriate so no client bears a loss as a direct result of these attacks.
IC Markets have been working frantically with oneZero and other service providers to put measures in place to prevent such attacks in the future. Some of the measures we have taken include adding another 15 MetaTrader 4 data centers (currently the most of any broker globally), working with ISPs to manage our traffic better and a complete overhaul of our NY4 setup and its redundancy to other data centers across the globe.
We value you as a customer and want you to know that we are doing everything in our power to make this right. If you were affected by the network disruptions over the last week or would like a call for a more comprehensive explanation then please contact our support team firstname.lastname@example.org.
My avatar explains "social trading" perfectly.