Montero (2022) explores a discontinuity in a land reform in El Salvador and reports two main findings. First, relative to outside-owned haciendas operated by contract workers, the productivity of worker-owned cooperatives is higher for staple crops and lower for cash-crop. Second, cooperative property rights increase workers' incomes and compress wage distributions. In this comment, we show that the latter result rests on two mistakes: three-quarters of the observations are duplicates and income inequality is calculated over too few workers to be meaningful.When corrected, the data sources and research design provide no credible evidence regarding the causal effects of ownership structure on income levels and inequality. * The comment is accepted at the Journal of Political Economy. The issues were identified during the Oslo Replication Games organized by the Institute for Replication. We thank Eduardo Montero for making the replication data and code freely available, and for his admirable response in support of research integrity in his personal communications with our team. We further thank the editor of the JPE, Emir Kamenica, and Abel Brodeur, Kalle Moene, Sahar Parsa and Oddbjørn Raaum for insightful comments. Replication files for this comment can be found here: https://andreaskotsadam.files. wordpress.com/2023/02/replication_montero.zip.* * We made the following change: The standard errors in columns 5 and 6 in table 1 were erroneously reported as 24.79 and 43.09. The standard errors are now reported as 43.09 and 84.53. We thank Rony Rodriguez-Ramirez for pointing out this error.