The standard model (SM) Higgs sector predicts exactly one physical Higgs boson with CP-even couplings to the SM particles. This year marks the 10th anniversary of the discovery of a boson with a mass of around 125 GeV that appears to fulfill this prediction. However, many extended Higgs sectors can also accommodate such a particle. These models usually predict modified couplings and/or properties of the 125 GeV boson, which can be directly tested by precision measurements at the LHC. Deviations in the observed Higgs boson properties, including its CP nature, would be clear signals of new physics and could help address several shortcomings of the SM, such as its inability to explain the observed excess of matter over antimatter in the universe. In this seminar, I will discuss the latest measurement of the Higgs bosonโs CP properties using the Hโ๐๐ decay process by the CMS Collaboration.