(at around 16 mins) James Wan was unavailable to return as director for the third installment due to his scheduling conflict with Furious 7 (2015). He makes a brief cameo as the theater director during Quinn's audition scene.
A trailer for the film was released in March of 2015 and featured the song "Afraid of Nothing" by Sharon Van Etten. The filmmakers used the song without acquiring the rights to it. When Van Etten was notified by a fan on Twitter, the filmmakers were forced to pay her for illegally using her music.
This third installment makes several references to ghosts and demons from the first two of the "Insidious" films, such as the Lipstick Face Demon, The Bride in Black, and possibly the Long-Haired Fiend.
Writer/Director Leigh Whannell told casting that he wanted The Man Who Can't Breath to look like the sloth victim in Se7en (1995). The same actor, Michael Reid MacKay, was cast for the role.