Your own source disputes what you say.

The original study did not include emissions from land use, land use change or forestry, or from sources such as landfills, agriculture and farming. It also did not include data on indirect emissions, which come from purchased energy such as heating and electricity, citing concerns about double-counting emissions attributable to corporations.

The study relied on data collected by the Carbon Majors Database, which focuses on greenhouse gas emissions data from the largest company-related sources. In other words, The data derives from records of carbon dioxide and methane emissions relating to fossil fuel (oil, gas and coal) and cement producers dating back to 1854.
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t’s difficult to discern how much total global emissions can be attributed to the top 100 polluting corporations, but there are ways to get a ballpark idea.

If you use the total global emissions calculated by the Climate Analysis Indicators Tool, an average of around 60% of global emissions can be traced back to those 100 companies from 1990 to 2015.