On February 9, 2015, Sony Pictures Studios and Marvel Studios announced that Spider-Man would appear in the Marvel Cinematic Universe, with the character appearing in a Marvel Cinematic Universe film and Sony releasing a Spider-Man film co-produced by Marvel Studios president Kevin Feige and Amy Pascal on July 28, 2017, with Sony Pictures continuing to own, finance, distribute, and having final creative control of the Spider-Man films.
In April 2015, Feige revealed that Marvel had been working to bring Spider-Man into the MCU since at least October 2014, when they announced their full slate of Phase Three films, saying, "Marvel doesn't announce anything officially until it's set in stone. So we went forward with that Plan A in October, with the Plan B being, if [the deal] were to happen with Sony, how it would all shift. We've been thinking about [the Spider-Man film] as long as we've been thinking about Phase Three."
Sony is also developing its own standalone films (Venom and Silver & Black) separate from the deal with Marvel Studios, which have been confirmed by Amy Pascal (in a joint interview along with Kevin Feige with Fandom powered by Wikia) to exist "in the same reality" as "Spider-Man: Homecoming",