Companies in the digital technology industry are significantly underreporting the greenhouse gas emissions arising along the value chain of their products. Across a sample of 56 major tech companies surveyed in a study by the Technical University of Munich (TUM), more than half of these emissions were excluded from self-reporting in 2019. At approximately 390 megatons carbon dioxide equivalents, the omitted emissions are in the same ballpark as the carbon footprint of Australia. The research team has developed a method for spotting sources of error and calculating the omitted disclosures.