The physical presence requirements on green card holders depend on many factors. Generally, a permanent resident should not be absent from the United States for more than six months per year. Otherwise, his or her status might be deemed abandoned. It is also advisable for an investor to keep genuine ties with the United States, including having a valid driver’s license, keeping a U.S. mailing address, etc. If an investor with a green card needs to be out of the U.S. for an extended period of time, it is of great importance that he or she applies for the necessary travel documents (re-entry permit) in advance to avoid any issues when trying to enter the country again as a permanent resident.