Josh Braun and Kevin Iwashina of Submarine concluded the deal with Magnolia's Tom Quinn and Eamonn Bowles at around 9pm on Monday (January 19) after marathon talks. Lance Rosen of Rosen Lewis was the comedy's legal representative.
Magnolia plans a nationwide on-demand release on its Ultra VOD platform followed by theatrical roll-out in at least 15 markets.
Meanwhile interest continued in Submarine titles The Cove, The End Of The Line and William Kunstler: Disturbing The Universe, while an international rights deal was in the works on When You're Strange.
Other Sundance titles in play last night included An Education, with offers now understood to have gone higher than $2m, Spread, I Love You Phillip Morris, World's Greatest Dad, Amreeka, In The Loop and Push: Based On The Novel By Sapphire.
Humpday, a US Dramatic Competition entry, is the third feature from Seattle film-maker Shelton. Mark Duplass, Joshua Leonard and Alycia Delmore star in the tale of male former college friends who decide to have sex with each other on camera and submit it to an amateur porn contest.
'On behalf of the entire cast and crew of Humpday, we are thrilled to be distributing this film via Magnolia,' Shelton said. 'They are among the best in the business at releasing specialty films and we look forward to a successful collaboration.'
Bowles called Shelton 'an incredible, truly original talent' who had delivered 'an amazing sleight of hand with her cast.'