Answer: Steven Spielberg
Prior to 1984, there were only four movie ratings: G, PG, R, and X general admission, parental guidance suggested, no one under 17 without an adult, and no one under 17 admitted at all.
This worked well for quite a few years, but in the early 1980s, a number of popular movies fell into a black of gray zone between the PG and R rating. Movies like Indiana Jones and the Temple of Doom Gremlins Poltergeist and Clash of the Titans were clearly too graphic in nature for the General Audience (G) rating, but not enough to get pushed up to the Restricted (R) rating. Essentially, the Parental Guidance (PG) rating had become the catch-all for everything in between the two extremes, and there was widespread public outcry when, suddenly, PG movies included the child of graphic violence found in movies like Indiana Jones and the Temple of Doom
Steven Spielberg, director of Indiana Jones and the Temple of Doom and producer of Gremlins agreed with the public sentiment and suggested a new rating to Motion Picture Association of America President Jack Valenti: PG-13. Spielberg pitched the new rating as a designation for movies that contain material inappropriate for preens, but not graphic enough to merit and R rating. The new rating was adopted in 1984, and the first film to hit the silver screen was Red Dawn .
While theater owners initially grumbled about the new rating and the potential for reduced revenue, they quickly changed their tunes. The PG-13 rating is a gold mine as teenagers flooded the theaters to watch movies the new rating. Previously, they had G and PG movies as being childish, but unable to attend R movies with any regularity. Now they had a slice of the movie production pie to call their own.