The file contains the raw isotopic data for the article entitled 'Neogene Caribbean elasmobranchs: diversity, paleoecology and paleoenvironmental significance of the Cocinetas Basin assemblage (Guajira Peninsula, Colombia)'. It includes the correction for the values first produced by our mass spectrometer and how the corrections were proceeded. Several runs were performed and these are detailed with comments and remarks. Any doubt or question about these corrections are welcomed by me, László Kocsis and Torsten Vennemann for discussion or further considerations.