According to the IPCC, the carbon footprint "measures the exclusive total amount of emissions of carbon dioxide (CO2e) that is directly and indirectly caused by an activity or is accumulated over the lifecycle stages of a product."

A company's total GHG emissions do indeed take these emissions into account, but other emissions are also accounted for. All direct and indirect emissions (upstream and downstream) must be taken into account. These include purchased services, capital goods, business travel, employee commuting, investments, etc.

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