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<p>The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) measured the middle-infrared limb emission spectrum of the atmosphere from 2002 to 2012 on board ENVISAT, a polar-orbiting satellite. Recently, the European Space Agency (ESA) completed the final reprocessing of MIPAS measurements, using version 8 of the level 1 and level 2 processors, which include more accurate models, processing strategies, and auxiliary data. The list of retrieved gases has been extended, and it now includes a number of new species with weak emission features in the MIPAS spectral range. The new retrieved trace species include carbonyl chloride (<span class="inline-formula">COCl₂</span>), also called <i>phosgene</i>. Due to its toxicity, its use has been reduced over the years; however, it is still used by chemical industries for several applications. Besides its direct injection in the troposphere, stratospheric phosgene is mainly produced from the photolysis of <span class="inline-formula">CCl₄</span>, a molecule present in the atmosphere because of human activity. Since phosgene has a long stratospheric lifetime, it must be carefully monitored as it is involved in the ozone destruction cycles, especially over the winter polar regions.</p> <p><span id="page7960"/>In this paper we exploit the ESA MIPAS version 8 data in order to discuss the phosgene distribution, variability, and trends in the middle and lower stratosphere and in the upper troposphere. The zonal averages show that phosgene volume mixing ratio is larger in the stratosphere, with a peak of <span class="inline-formula">40</span> <span class="inline-formula">pptv</span> (parts per trillion by volume) between <span class="inline-formula">50</span> and <span class="inline-formula">30</span> <span class="inline-formula">hPa</span> at equatorial latitudes, while at middle and polar latitudes it varies from <span class="inline-formula">10</span> to <span class="inline-formula">25</span> <span class="inline-formula">pptv</span>. A moderate seasonal variability is observed in polar regions, mostly between <span class="inline-formula">80</span> and <span class="inline-formula">50</span> <span class="inline-formula">hPa</span>. The comparison of MIPAS–ENVISAT <span class="inline-formula">COCl₂</span> v8 profiles with the ones retrieved from MIPAS balloon and ACE-FTS (Atmospheric Chemistry Experiment – Fourier Transform Spectrometer) measurements highlights a negative bias of about <span class="inline-formula">2</span> <span class="inline-formula">pptv</span>, mainly in polar and mid-latitude regions. Part of this bias is attributed to the fact that the ESA level 2 v8 processor uses an updated spectroscopic database. For the trend computation, a fixed pressure grid is used to interpolate the phosgene profiles, and, for each pressure level, VMR (volume mixing ratio) monthly averages are computed in pre-defined 10<span class="inline-formula">^∘</span> wide latitude bins. Then, for each latitudinal bin and pressure level, a regression model has been fitted to the resulting time series in order to derive the atmospheric trends. We find that the phosgene trends are different in the two hemispheres. The analysis shows that the stratosphere of the Northern Hemisphere is characterized by a negative trend of about <span class="inline-formula">−</span>7 <span class="inline-formula">pptv</span> per decade, while in the Southern Hemisphere phosgene mixing ratios increase with a rate of the order of <span class="inline-formula">+4</span> <span class="inline-formula">pptv</span> per decade. This behavior resembles the stratospheric trend of <span class="inline-formula">CCl₄</span>, which is the main stratospheric source of <span class="inline-formula">COCl₂</span>. In the upper troposphere a positive trend is found in both hemispheres.</p>