Kanye West is suing over footage leaked of his proposal to Kim Kardashian.

The 'New Slaves' hit-maker and his fiancée are suing Youtube co-founder Chad Hurley who they claim ''manipulated'' his way into AT&T Park in San Francisco and released unauthorised footage of the moment the rapper popped the question to the reality star on October 21.

Court documents obtained by gossip website TMZ reveal the couple are accusing Chad of using the footage - which later went viral - to help launch his new internet venture MixBit in a desperate bid for a successful ''second act'', as two of his other businesses have flopped since he sold YouTube for $1.65 billion.

Only close friends and family were invited by Kanye to witness the lavish proposal, and while prominent Silicon Valley founders were in attendance, Chad had not been invited but was allowed to stay under the condition that he sign a confidentially agreement.

The document also states: ''Hurley proceeded to try to turn the event into one starring himself, broadcasting the images he knew were the exclusive property rights of someone else.''

The footage was intended to be shown on MC Cable Television, which is an arm of Bunim/Murray and E!, which produces and broadcasts Kim's reality show, but Chad published a press release about the video and tweeted it to his followers.