The US government is forcing all companies to pay a mandatory tax of 15.5% on all overseas profit that was designated as "indefinitely reinvested" under the previous tax regime. This is a mandatory one-time tax as part of a shift to a territorial system. Multinationals can do whatever they want with the cash, but considering that they've been lobbying government on a repatriation bill for over a decade specifically to be able to do domestic M&A, pay dividends, or do share buybacks, it's pretty obvious that all of that cash is coming back to the US. A business that wants to reinvest all their cash internationally is free to do so (and in fact the previous tax regime incentivized it), but they're going to be paying US tax on what they've accumulated so far.
