As with most eBay auctions, it came down to the final day.
On Sunday, bidding for a pristine copy of Action Comics #1, the publication that introduced the Man of Steel, increased by a full million dollars. In the end, one bidder edged out another by just $100. Final purchase price: $3,207,852.00
Part of the proceeds from this sale will go to the Christopher & Dana Reeve Foundation. The vintage comic was published June 1, 1938.
[H/T: Marc Graser]