This paper analyses the boom on the Dutch art market during World War II. It relies on an original database covering all pictures - over 11,000 - sold at Mak van Waay, one of the two premier Dutch auction houses during the occupation. Hedonic regressions show that in real terms, the price of paintings increased more than fivefold between 1940 and 1945. While there was significant demand for Old Masters by the German occupying forces, paintings from the Romantic period outperformed Old Master and Modern paintings. These prices prompted forgers to create fake artworks. Reputable auction houses such as Mak van Waay used their cataloguing of artworks to signal quality and authenticity. We take advantage of these data to create indicators for ‘forgery’ and ‘doubtful attribution’. Prices reflect this flagging, as suspected forgeries sold for significantly less, as did pictures with questionable attributions. ... : Journal for Art Market Studies, Vol 1, No 1 (2017) ...