Moving shadows and pressure bumps: What we learn from multi-epoch, multi-wavelength observations The disk around the isolated Herbig Ae star HD169142 has been studied extensively at multiple wavelengths. Combining our new data with literature, covering 6 years in total, we find that this disk is harbouring a number of new exiting features. In addition to its several rings showing azimuthally asymmetric sub-structures and one of the most promising proto-planet candidates, our analysis points towards a new, additional suspect: A moving surface brightness dip consistent with a shadow cast by a massive, dust-surrounded 1-30Mj protoplanet on an orbit comparable to Jupiter’s. Further, we find the first observational indications for temperature-induced instabilities in the ring and trace a pressure maximum spatially resolved. In my talk, I will present the multi-epoch, multi-wavelength observations, radiative transfer and hydrodynamical simulations which lead to these findings and suggest that HD169142 might be a young version of a multiple massive planet system such as HR8799.