J. Michael Cline -- founder of movie ticketing app Fandango -- has died after leaping from a building in New York City ... TMZ has confirmed.

Law enforcement sources tell us ... the entrepreneur jumped from the 20th floor of The Kimberly Hotel in Manhattan, landing in a third-floor courtyard early Tuesday morning.

We're told he left a suicide note in the room that reads, "So sorry. I can’t explain the pain of f****** up this much. I love you all." Our sources say he then went out onto the balcony and jumped.

Cline started up Fandango way back in 2000 and also held roles with start-up funding firms Accretive and Juxtapose. Other companies he founded ... tech company R1 RCM, business insurance firm Insureon, and education solutions business Everspring.

Cline married his wife Pamela back in 1995, and the two share six children together. They bought their Palm Beach home back in late 2020 for just north of $20 million, according to the Palm Beach Daily News.

Cline was 64.

RIP

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