From the publisher's website:
GMC - it's Game Master's Choice - is a small roleplaying game publishing company based out of Berlin, Germany. Since 2005, we publish PDF based OGL roleplaying game products. Starting in 2009, we sell merchandise with GMC art at Spreadshirt and CafePress. For players, game masters, and other publishers alike they are currently available at DriveThruRPG, Fantasy-Download, Paizo, and RPGNow.