GILD, which is rolling in dough, wants to raise even more
We have to remember that Gilead has huge foreign sales, somewhere in the 50% range, so while we don't know where their cash is, it would be logical that they would have to repatriate some foreign cash first for use in the U.S..
Considering the Federal and State tax rates it is often much cheaper to borrow locally no matter what the rates are. This is especially true if they have a hunch that the U.S. might eventually get around to changing the rates.