Mark Zuckerberg’s backyard privacy showdown has grown more tangled with competing claims about a mysterious African prince and a private eye accused of bullying a witness.

The Facebook Inc. founder is accused in a real estate developer’s lawsuit of reneging on a promise to introduce him to Silicon Valley’s elite as part of a $1.7 million deal that ended plans for a mansion with a view into the 31-year-old billionaire’s bedroom.

Zuckerberg’s lawyers claim that after digging into developer Mircea Voskerician’s version of events, they aren’t convinced a prince who purportedly offered 2 1/2 times that for the property rights really exists.

Voskerician contends the true objective of Zuckerberg’s detective was to intimidate a witness.

The current squabble comes in a dispute that has already exposed internal Facebook e-mails and spurred a $39 million real estate shopping spree to protect the tranquility of Zuckerberg’s two-story home in Palo Alto, California. As the two sides cast aspersions aimed at undermining the other’s credibility, the case moves closer to a trial scheduled for November that may air even more unseemly details.

Whether the developer conjured up a competing offer to make his lawsuit more compelling may prove to be one of those details.

‘Discount’ Price

Zuckerberg’s lawyers, aided by San Francisco private investigator Zachary Fechheimer, have been investigating a $4.3 million offer Voskerician said he turned down. The developer said he gave Zuckerberg a “discount” price because of the business introductions included in the deal.

James Sagorac, a friend of Voskerician’s who was acting as an intermediary for the original offer, initially refused to name the client he was representing, Zuckerberg’s lawyers said. Under a judge’s order, Voskerician’s lawyer provided Zuckerberg with contact information for Sagorac’s client, identified as a lawyer in South Africa, according to a state court filing in San Jose, California.

The South African, who Zuckerberg’s lawyers said they weren’t able to confirm was registered as a lawyer in that country, disclosed that the offer was made on behalf of a prince, according to the filing.