Our paper, Experimental Bound Entanglement?, by Jonathan Lavoie, Rainer Kaltenbaek, Marco Piani, and Kevin Resch was published in Nature Physics. This work comments on a claim of experimental bound entanglement published late last year in the same journal.
Concluding paragraph of our comment: Undistillability is the one property that makes an entangled state bound. Amselem and Bourennane’s results fail to show undistillability and thus they cannot claim to have produced bound entanglement.
See here for the original paper and the authors’ reply to our comment. See also our recently published results [J. Lavoie et al. Physical Review Letters 105, 130501 (2010)] on experimental bound entanglement where, for the first time, we definitively show both properties of bound entanglement: entanglement and undistillability.