Presentation #116.90 in the session Stellar/Compact Objects.
Ultraluminous X-ray sources are accreting compact objects radiating above the Eddington limit for a stellar mass black holes. A large fraction of them is constituted by accreting neutron stars, some detected as pulsars (Pulsating ULXs, or PULXs). ULXs have a rich timing phenomenology, from QPOs to super-orbital periods. A few PULXs have been studied in high detail, showing quite extreme behavior in their spin down/up and, in one case, a robust measurement of orbital decay. In this talk, I will review the timing properties of ULXs, and I will use a multi-year campaign of NuSTAR observations of M82 X-1 and X2, the two ULXs in M82, to show how their timing properties can be used to infer their physical properties.