One of the main aspects of public debate in Brazil in the period that preceded the 2018 presidential elections was the dissemination of false stories via social media and messaging apps. Disinformation, misinformation and mal-information – phenomena that comprehends, among others, elements such as wrongful, out of context, distorted and fabricated information – were a major concern in the context of the election, which could be seen in the number of false stories debunked by independent fact-checkers. In the 20-day period between the two rounds of the presidential election, six fact-checking websites posted 228 verifications of false stories disseminated through social media and/or messaging apps, which covered about 132 different topics. This research aims to identify which were the topics of those false stories and analyze the categorizations enunciated in their discourses. In order to do so, the methodological perspective utilized was the Membership Categorization Analysis (MCP), affiliated with the tradition of Ethnomethodology, applied to the false stories discourses as quoted by the fact-checking websites.