LOS ANGELES (CN) - Kim Kardashian and Kanye West accuse YouTube co-founder Chad Hurley of crashing their private marriage proposal and posting video of the event to promote his new video-creation app, MixBit.
Hurley and his tech company AVOS Systems are named in the Superior Court lawsuit, which seeks unspecified damages for breach contract, fraud and unjust enrichment.
West and Kardashian say Hurley "finagled" his way into the private event at the San Francisco Giants baseball stadium on Oct. 21, where the rapper surprised the reality TV star by proposing on her 33rd birthday.
Hurley only got access to the party because he tagged along with a guest, the newly engaged couple claim, and was allowed to stay on the condition that he promise - in writing - not to publish or post any images of the party.
The complaint includes a photograph that purportedly depicts Hurley holding a signed copy of the confidentiality agreement.
The 2.5-minute video was still online Friday. It shows West, on bended knee, proposing to Kardashian in the middle of a baseball diamond while an orchestra plays behind them. Family members and guests then run toward the celebrities to congratulate them.
"Immediately after giving his word to honor the condition required for his attendance at the event, Hurley turned around and violated the condition," the 12-page lawsuit states. "Hurley filmed the event - which turned out to involve not merely a birthday celebration for Kardashian, but also an unexpected engagement proposal by West - and then posted it on MixBit."
The couple claim Hurley also tweeted about the event to "the better part of a million people" and published a press release that circulated to Vanity Fair and other publications.
"That Hurley did these things out of desperation is readily apparent," the couple claim. Though Hurley sold YouTube to Google for a reported $1.65 billion, his subsequent ventures, including a Formula One racing team and the Zeen web service, did not fare so well, according to the lawsuit.
"With consecutive flops on his hands, Hurley then launched MixBit, which also quickly ran into trouble," the couple claim. They say Hurley "needed something spectacular" to make up for MixBit's "lackluster launch" on Aug. 8.
"When Hurley heard of the event, to which he was not invited, he saw his opportunity to crash the party on the coattails of an invited guest and then steal plaintiffs' property."
MixBit has been described as a cross between Twitter's Vine and Facebook's Instagram, allowing users to mix and edit videos recorded on their smartphones.
West and Kardashian claim that "the very business model of MixBit -- one which allows interactive manipulation of images between the person posting an image, and anyone else in the world who wants to change, mock or denigrate it - made it virtually inevitable that the misappropriated images of West proposing to Kardashian would soon be distastefully altered."
The pair are represented by Eric George of Browne George Ross.