A prerequisite for the successful manufacture of a biopharmaceutical in mammalian cells is a cell line development strategy that selects a cell line with the most desirable properties from a heterogeneous transfectant population. Desirable attributes include the stable, high expression of product with the appropriate critical product quality attributes rapidly, reproducibly and with relative ease. Obtaining a host cell line that inherently exhibits such desirable biomanufacturing attributes can therefore have a significantly positive effect on the identification of recombinant cell lines with desired traits during cell line development screens. In this study, we demonstrate that it is possible to exploit intrinsic heterogeneity within host cell populations and identify host cell lines which are more “fit for purpose”.