It does require a warrant.
This is the position I took when I wrote about this subject the first time. Evidently Antoine Jones took his case all the way to the Third Circuit Court of Appeals, or at the very least is riding on the coattails of others who did.
Like I said before, there is no big defense Antoine Jones gets to bring to bear here: he got caught with a buttload of cocaine and a mountain of cash. However, the manner in which those things were discovered is also indefensible so at best the cops can only apprehend the coke and the money and Jones gets a Get Out Of Jail Free card.
This time. With a haul like that we can safely assume it isn't Jones' first trip to the Coke machine and probably not his last. He'll get nailed good and proper soon enough, never fear.
Courts in other districts have ruled that warrantless GPS tracking is admissible in court as evidence; I find it strange that the Third Circuit Court would differ and wonder how the conundrum would be settled if a plaintiff used one court's stance for precedent and the defendant used another court's stance for defense. It could become a pretty silly slapfight pretty quickly.