EU competition commissioner Margrethe Vestager reportedly circulated a 130-page ruling for official release tomorrow, concluding that Ireland's tax deals with Apple (as well as other US companies) constituted unlawful state aid to a select group of businesses. Apple will reportedly be called on to pay back taxes that, according to anonymous sources, could total "billions of euros" — Bloomberg quotes an estimate of up to $19 billion, although The Irish Times suggests it could go as low as €100 million, or around $112 million. The decision is likely to be appealed by both Apple and the Irish government.

Tomorrow's ruling concludes one chapter of an investigation that's been running since 2014, when EU officials began scrutinizing tax deals made in 1991 and 2007.