[_delirium]

Afaik, incorporation in Delaware isn't usually tax-related; most Delaware corporations don't actually book their income in Delaware, but are registered there because of favorable corporate law and a business-friendly civil trial system.

You're right on the deferral/transfer with regards to international income (e.g. income Apple books in Ireland and later uses to pay for something in Cupertino), but I don't believe Apple ever pays California income taxes on the income it books in Reno, even if it immediately turns around and uses that income to pay Cupertino salaries. There's no state-to-state equivalent of repatriating income.