With the U.S. Senate reportedly finishing an investigation into how Apple and others dodge taxes, and with Apple fighting for an officially sanctioned tax holiday, it’s worth taking stock of Apple’s tax liabilities. Dealing with the tax man, it turns out, could cost the company upward of $28.5 billion or send it on a shopping spree abroad.

Even as Apple lobbies for corporate tax amnesty, it has accounted for some of its potential future tax bills in filings with federal securities regulators, a move that helps Apple avoid embarrassing earnings re-statements if it is later forced to pay taxes. In the filings, Apple says it had $14.7 billion in deferred tax liabilities overseas as of Sept. 29, when its fiscal year ended. In a footnote, the company acknowledges there’s another $13.8 billion in “unrecognized deferred tax liability” from money it intends to keep perpetually out of the U.S. If the company ever decides to bring all its money home, and then pays taxes on it at currently anticipated rates, the bill would come to $28.5 billion, plus additional taxes on any profits moved overseas since Sept. 29.