Mark Zuckerberg’s wedding raises question of a prenup

In this marriage, the stakes are high.

This past Saturday, one day after Facebook made its stock market debut, founder Mark Zuckerberg married his long-time girlfriend, Priscilla Chan. This had the media world carrying out another type of speculation.

The point in question is whether or not the newlyweds had made a prenuptial agreement, as Donald Trump had advised last week before any news of the surprise wedding had surfaced.

"They get married, and then for some reason over the next couple of years they get divorced and then she sues him for 10 billion dollars US, and she hits the jackpot," Trump tells CNBC.

Toronto family lawyer Julie Stanchieri agrees.

"It's always a good idea when there is a dramatic difference in income to have a prenup in place," says Stanchieri. "It makes things clear, and it means there's less to fight about down the road."

"Not to say they won't find another reason to fight," she adds.

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Although Chan will probably make a good income, as she's just graduated from medical school and plans to practice as a pediatrician, it's not on the scale of Zuckerberg's finances. He's only 28 and is already worth around 17 billion dollars, as we found out when the Facebook shares went public on Friday.

It's curious that the wedding came just after the size of the Facebook founder's fortune was revealed, especially considering that California's community property law excludes any money accrued before marriage from the communal pot. But what's unclear in their case, is whether the growth of Zuckerberg's Facebook shares would become joint income.

Canada has similar rules. In Ontario, for example, most money and assets that were acquired before a marriage don't automatically get split up in a divorce settlement.

"When we add up what needs to be divided at the end of a marriage, you can deduct everything that you brought into the marriage," says Stanchieri, "with the exception of the matrimonial home."

Also see: Ex-wife gets revenge by selling husband's stuff in garage sale

When it comes to income gained throughout the marriage, though, there can be some surprises.

"People are often surprised that non-financial contributions to a marriage are calculated to be similar to financial contributions," Stanchieri explains. "At the end of a lengthy marriage the primary breadwinner doesn't always understand why he or she has to share income with the other spouse."

Stanchieri is seeing more people getting prenups in her practice. As people are getting married later and becoming more established before settling down, they have more to lose in a divorce.

"If you have a house, you might be alarmed to know that the day you get married your spouse will be entitled to a portion of that house," she says. "If you didn't have any assets to start, you probably wouldn't be so concerned about it."

Considering Chan reportedly made Zuckerberg agree to a set of terms before she moved to California to be near him, including that they'd have one date per week, and one hundred minutes of time alone, she doesn't sound like the type who would avoid laying down some ground rules.

Watch the video below about how to survive the end of a long-term relationship.