BTC-e is one of the more experienced exchanges, which started Live trading in August 2011. It is still one of the biggest Bitcoin exchanges.
Bitfinex was founded in 2013, and has its office in Hong Kong. The platform is owned and operated by iFinex Inc., which is registered on the British Virgin Islands (BVI). Trades Three cryptocurrencies can be traded on Bitfinex and fiat trades are limited to USD. Next to Bitcoin, …
Update October 17, 2014: The MintPal relaunch has failed and Moopay LTD has announced it is filing for bankruptcy protection taking MintPal with it.
Kraken is part of Payward, Inc. which has been around since 2012. The exchange is based on the U.S. and has its headquarter in San Francisco, California.