Results supported H1a, showing autonomous motivation was significantly and positively related to knowledge-sharing frequency and usefulness. However, no support was found for H1b, as autonomous motivation was not significantly related to any form of knowledge hiding. No support was found for H2a, with external regulation positively related to knowledge sharing frequency, contrary to expectations. Providing partial support for H2b, external regulation was significantly and positively related to evasive hiding and playing dumb. Results of indirect effect tests through bootstrapping pro- vided support for H3a and H5a, showing autonomous motivation mediated the effect of cognitive job demands on knowledge-sharing frequency, B = 0.17, p < 0.001, and usefulness, B = 0.19, p < 0.05, and the effect of job autonomy on knowledge sharing frequency, B = 0.26, p < 0.001, and usefulness, B = 0.28, p < 0.001. However, no support was found for H3b and H5b, as no significant indirect effects of cognitive job demands and job autonomy on knowledge- hiding outcomes via autonomous motivation emerged. As in Study 1, no support was found for H4a and H4b, as task interdependence was not related to knowledge sharing or hiding via autonomous motivation. Although not expected, results revealed that external regulation significantly mediated the effect of task interdependence on knowledge-sharing usefulness, B = 0.09, p < 0.05, as well as the three dimensions of knowledge hiding: evasive hiding, B = 0.17, p < 0.05; playing dumb, B = 0.23, p < 0.001; and rationalized hiding, B = 0.21, p < 0.05.