Google co-founder Larry Page is set to marry his girlfriend, Lucy Southworth, this weekend on a tiny private island in the Caribbean, US media reports say.
Six hundred guests are reportedly due to attend the ceremony on Necker Island in the British Virgin Islands, owned by the best man, Sir Richard Branson.
Ms Southworth is a doctoral student at Stanford University in California. Mr Page, who has an estimated fortune of $18.5bn (£9bn), co-founded search giant Google with Sergey Brin in 1998.
Since listing in August 2004 shares in the firm have risen sevenfold and it is now valued at over $220bn (£108bn). Mr Brin, who is the joint fifth-richest person in the US along with Mr Page, got married in the Bahamas earlier this year.
Mr Page, 34 and Ms Southworth, 27, have reportedly been dating for over a year. It is not known if they have signed a pre-nuptial agreement.
Although neither the couple nor Google have confirmed any of the speculation about their impending marriage, a number of reports in the US media concur that the ceremony will be held on Necker Island this weekend.
The New York Post reported on Wednesday that 600 guests - among those who have allegedly been told they need only keep the weekend of 8-9 December free and have a valid passport - would be flown on private planes to Sir Richard's private getaway.
Wedding planners booked up all the hotels on the neighbouring island of Virgin Gorda six months in advance to secure accommodation for the guests, the Post said. Boats and ferries for the hundreds of guests have also been ordered.
Sir Richard bought the previously uninhabited island in the 1970s and built a 14-bedroom holiday home there. The island, which can be hired privately for $46,000 (£22,000) per night, has become a favourite of the rich and famous.
Sir Richard and Mr Page have reportedly become good friends in recent years.
He enlisted the services of Google Earth to help search for his friend, the adventurer Steve Fossett, when his aircraft went missing in September.
Although the guest list is a closely-guarded secret, the former US President, Bill Clinton, his wife and presidential hopeful Hillary Clinton, U2 singer Bono, as well as several other billionaires and Silicon Valley visionaries are thought to have been invited.