The datasets and code provided on PICMUS are free of use. The only request is to refer properly to PICMUS - The Plane Wave Imaging Challenge in Medical UltraSound and quote the following proceeding paper.

Liebgott, H., Rodriguez-Molares, A., Jensen, J.A., Bernard, O., "Plane-Wave Imaging Challenge in Medical Ultrasound", in IEEE International Ultrasonics Symposium, Tours, France., 2016, p. accepted