Coinbase.com is NOT an exchange, it is NOT a service... it is a company made for the SOLE purpose of being a front for their trading activities and using customer funds as a hedge for their bad trades.
I don't know where to begin when it comes to coinbase.com being dishonest in their practices, website, terms of service, and blog responses... all to defraud the customer. For some of the customers that they defraud via the "high risk transaction" scheme, they actually recreate the original transactions and make it right. For others (most likely the larger amounts they pocket), they simply never respond, leaving you hanging and burning.
They even give you back the money they steal from you SOME of the times, to make it look like they are not a total scam. Other times, they pocket the money and simply stop responding to you or respond with this email:
Trance,
Sorry for the confusion here. We use machine learning algorithms to prevent fraud and they're not always 100% accurate. If you feel you've had a transaction cancelled incorrectly send support an email. We regularly review transactions and push them through at the original purchase price upon request. I also wrote a bit about our fraud program in the fourth section here:
http://newsbtc.com/2013/11/07/coinbases-olaf-carlson-wee-answers-questions-users-technical-issues/Hope that helps!
This is just a straight up lie, they don't regularly push transactions through at original purchase price upon request. They didn't do it for me because the amount was so high.
From what i've known, none of the higher amts where they have ripped people off have they refunded. Only small amts.