Mt. Gox Opens on a Dormant Card-Game DomainMt. Gox Opens on a Dormant Card-Game Domain

In January 2007, Jed McCaleb registered the domain mtgox.com (Magic: The Gathering Online eXchange), intending to build a site where players could trade cards. The project never shipped. Three years later, that same dormant domain became Bitcoin's most important infrastructure, handling the majority of global Bitcoin trading at its peak before collapsing in one of the most consequential exchange failures in financial history.

The Man Who Built ItThe Man Who Built It

McCaleb was not an amateur experimenting with a weekend project. Before Bitcoin, he had built eDonkey2000, one of the largest peer-to-peer file-sharing networks in the world. At its peak the eDonkey network had over 4 million simultaneous users. The RIAA eventually took legal action, and McCaleb's company MetaMachine paid $30 million to settle in 2006 and ceased distributing its software. McCaleb was left without a primary project and looking for the next thing.

He discovered Bitcoin through a Slashdot article in June 2010, the same piece that brought a wave of early adopters into the community. He recognized that Bitcoin had no serious exchange infrastructure. Bitcoin Market, launched in March 2010 by a forum user called dwdollar, offered basic trading but no real order book and no automated matching. McCaleb saw a gap and filled it using what he already had: a domain name, some server infrastructure, and a few weeks of development time.

The Launch and What It ChangedThe Launch and What It Changed

The announcement, posted on Bitcointalk on July 18, 2010 at 1:57 AM, is a study in understatement: "I just put up a new bitcoin exchange. Please let me know what you think." That post, now archived at https://bitcointalk.org/index.php?topic=444.0, generated immediate discussion about features, spreads, and security. McCaleb clarified that all trades matched between users, that prices reflected real bids and asks rather than operator-set rates, and that the site was on dedicated hosting running continuously.

The functional difference from what came before was significant. Before Gox, if you wanted to buy Bitcoin you either found someone willing to sell in a forum thread, worked through a slow manual process with Bitcoin Market, or tried peer-to-peer trades that required trust in a stranger. Gox provided what a modern exchange provides: a live order book, real-time price data, 24-hour volume figures, and automated settlement. The first trade on the platform priced Bitcoin at $0.05.

The Sale and Its ConsequencesThe Sale and Its Consequences

McCaleb ran Gox for less than eight months. By early 2011, the compliance requirements for operating a money-transmitting service had grown complex enough that he decided to pass the business to someone willing to handle them. He sold to Mark Karpeles, a French developer living in Japan, with the stated explanation that the exchange needed "someone better able to take it to the next level."

What followed under Karpeles is well documented: years of security failures the exchange concealed from users, a hack that drained 630,000 BTC in 2011 that was never publicly disclosed at the time, and eventually a 2014 collapse that wiped out 850,000 BTC belonging to customers and the exchange itself. McCaleb, who had already moved on to co-found Ripple and later Stellar, bore no responsibility for any of it.

The arc from McCaleb's one-sentence forum post to Karpeles's bankruptcy filing is 16 years old today. The domain McCaleb almost used for trading game cards became the address where Bitcoin's price was set for the better part of four years, and the place where its largest single theft occurred.

Part of an ongoing series on Bitcoin history. This event falls on July 18, 2010.