Originally Posted by HomelessScientist
Hmm, is this really true??? I have never been through MIA, but in every US customs area I have used, there have been frequent announcements to the effect of "All passengers must claim their bags regardless of final destination."
They do make that announcement because a lot of infrequent passengers assume that their bags are checked all the way through (as on a domestic to domestic connection). I used to work at A-35/37 at DFW (where passengers used to exit customs before Terminal D opened) and can't tell you how many people (connecting to domestic flights) came up oblivious to the fact that their bags were on the baggage claim in customs...
I have flown MAD-MIA-GRU several times. You will have a red sticker on your bags that says "International Connection. Do not return bag to customer in US."
It's definitely true.