In particular, in case of dispute, the Court has the authority to adjudicate the dispute. It's the authority the Court used to hear Ex parte Garland in the first place.
And to my knowledge, there has never been a case that considers the President's ability to pardon for all possible crimes that could be filed related to some action. So if a subsequent President chooses to tack on a fourth crime to the list of three Snowden is currently charged with, a Trump pardon would likely not attach. At least, it would be up to the Court to decide if it attaches.
However, subsequent rulings call into question the absolute scope of Ex parte Garland (https://digitalcommons.law.wne.edu/cgi/viewcontent.cgi?artic...).
In particular, in case of dispute, the Court has the authority to adjudicate the dispute. It's the authority the Court used to hear Ex parte Garland in the first place.
And to my knowledge, there has never been a case that considers the President's ability to pardon for all possible crimes that could be filed related to some action. So if a subsequent President chooses to tack on a fourth crime to the list of three Snowden is currently charged with, a Trump pardon would likely not attach. At least, it would be up to the Court to decide if it attaches.