News that CBS' perennially popular sitcom The Big Bang Theory would be ending after its upcoming twelfth season rocked fans around the world yesterday and, after the dust has settled, the reason for the cancellation is becoming public.

Reports indicate that while the cast were in the middle of negotiations to renew their contracts for a potential thirteenth and fourteenth season, star Jim Parsons elected not to renew his contract. As the breakout, fan-favorite character of the series, CBS decided instead to end the series after the conclusion of Season 12 rather than attempt to carry on without him.

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Earning nearly $1 million per episode, Parsons' decision to walk away from the longrunning CBS series was evidently not a financially motivated one but rather that the actor simply wanted to pursue new projects after committing twelve years starring on the popular comedy series.

It is unclear at this time if Parsons will continue to reprise the role of Sheldon Cooper providing voiceover narrations for the prequel series Young Sheldon as the spinoff prepares to return for its second season on Monday, September 24 ahead of the Season 12 premiere of The Big Bang Theory.

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After twelve years leading the longest running single-camera television comedy series of all time, Parsons has certainly put in the time to move on to different things.

Starring Johnny Galecki, Jim Parsons, Kaley Cuoco, Simon Helberg, Kunal Nayyar, Mayim Bialik, and Melissa Rauch, The Big Bang Theory returns Monday, September 24, at 8 p.m. ET/PT on CBS before moving to its regular night on Thursday, September 27.

(via Entertainment Weekly)