After quite sometime of operation the Diablo 3 Auction House on the PC will be taken down. Both the gold and real money auction house will be shut down on March 18th, 2014. Here’s a snip from Blizzard’s FAQ page.
The gold and real-money auction houses have provided a convenient and secure system for trading, but it’s also become increasingly clear that despite the benefits they provide, they ultimately undermine Diablo’s core gameplay. A big part of Diablo is the thrill of battling demons and finding epic loot. While buying epic loot in the auction houses might be more convenient, it doesn’t feel anywhere near as heroic as plowing through a pack of fearsome-looking monsters and having them drop that one awesome item that seems like it was made for your character.
Furthermore, there is also an official video announcement on the shutdown as well: