Abstract: The mechanism avoids the rate variations due to the effect of gravitation on a regulating organ of a timepiece whose regulating organ includes a sprung balance and an escape wheel mounted onto a platform. The platform includes a counterweight and is mounted so as to freely rotate about at least a first axis relative to a plate of the movement so that this platform will rotate about the first axis under the effect of terrestrial gravitation. This mechanism includes a wheelwork with a driving kinematical chain linking the escape wheel to a barrel system of the timepiece, and a corrective kinematical chain compensating the movements and speed of the platform relative to the plate, so that these movements of the platform will not perturb the chronometry of the timepiece.