According to Deadline, Smith has decided not to battle aliens in the follow-up which is currently scheduled for a July 4th, 2016 release. The reason for that date would be to mark the 20th anniversay of the original, a movie which grossed a whopping $811 million worldwide and turned Will Smith into a global megastar.
However, the lack of the former Fresh Prince isn’t going to stop Independence Day 2 from moving ahead. Emmerich and Dean Devlin wrote the first draft of the script, and when handing it over to James Vanderbilt (The Amazing Spider-Man), they hatched two distinct stories, with Vanderbilt since working on two separate scripts, depending on Smith’s involvement. One has Smith as the hero of the film, whilst the other takes the battle to the aliens without him. The original report does caution that Smith has been on the fence about whether or not to return, but seem confident that he has passed on the project as of right now.
Another franchise that Smith will be saying goodbye to is Men in Black. Despite the success of the third instalment, the huge amount they had to pay the stars of the film has led to difficulty in Sony making much money from the franchise, and it looks like the studio are now keen to reboot the series.