$50 < m_{4\ell} < 105\GeV$. In the case of the measurement of the ratio of the ${\ensuremath{\PH \to 4\ell}\xspace}$ and ${\ensuremath{\PZ \to 4\ell}\xspace}$ cross sections, the mass window of $50 < m_{4\ell} < 140\GeV$ is used.

Measurement methodology {#sec:Methodology}
=======================

The aim is to determine the integrated and differential cross sections within the fiducial phase space, corrected for the effects of limited detection efficiencies, resolution, and known systematic biases. In order to achieve this goal, we estimate those effects using simulation and include them in the parameterization of the expected $m_{4\ell}$ spectra at the reconstruction level. We then perform a maximum likelihood fit of the signal and background parameterizations to the observed $4\ell$ mass distribution, $N_{\text{obs}}(m_{4\ell})$, and directly extract the fiducial cross sections of interest ($\sigma_{\mathrm{fid}}$) from the fit. In this approach all systematic uncertainties are included in the form of nuisance parameters, which are effectively integrated out in the fit procedure. The results of measurements are obtained using an asymptotic approach [@Cowan:2010js] with the test statistics based on the profile likelihood ratio [@LHC-HCG]. The coverage of the quoted intervals obtained with this approach has been verified for a subset of results using the Feldman-Cousins method [@Feldman:1997qc]. The maximum likelihood 