S. Linn and M. Kok, The Netherlands Cancer Institute for contributing samples for the AI cohort. Finally, we thank all members of the ICGC Breast Cancer Working Group. This work has been funded through the ICGC Breast Cancer Working group by the Breast Cancer Somatic Genetics Study (a European research project funded by the European Community's Seventh Framework Programme (FP7/2010-2014) under the grant agreement number 242006) and the Triple Negative project funded by the Wellcome Trust (grant reference 077012

A. L. Smid, S. M. , J. W. Stratton, S. M. , S. N. et al., Smid was supported by the EU-FP7-DDR response project. C.D. was supported by a grant from the Breast Cancer Research Foundation. J.E. was funded by The Icelandic Centre for Research (RANNIS), Farber/Harvard Cancer Center SPORE in Breast Cancer (NIH/NCI 5 P50 CA16 8504-02). A.M.S. was supported by Cancer Genomics Netherlands (CGC.nl) through a grant from the Netherlands Organization of Scientific research (NWO). M

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