For Facebook founder and CEO Mark Zuckerberg, it was quite a week – from birthday, to IPO, to I DO.

Mark Zuckerberg married his longtime sweetheart, Priscilla Chan on Saturday — but surprisingly, didn’t add a “Relationship Status” to his Facebook page.

A day after taking his company public, Zuckerberg added a “Life Event” on Facebook, posting a photo that shows him wearing a suit and tie with the knot loosened rather than his trademark hoodie.

Standing next to him in the picture is a woman in a white gown and veil. Above the photo are the words “Married Priscilla Chan.”

The photo had been “liked” by 289,086 people as of around 11:30 p.m., two hours after it was posted. Chan’s Facebook page updated her status as married to Mark Zuckerberg. The same photo posted there had been “liked” 3,784 times.

The ceremony took place in Zuckerberg’s backyard before fewer than 100 guests, who all thought they were there to celebrate Chan’s graduation.

The two tied the knot in an intimate ceremony at his Palo Alto, California, home, in front of fewer than 100 people, said a guest who spoke to the Associated Press on the condition of anonymity.

The nuptials capped a busy week for the couple.

Chan graduated from medical school at the University of California, San Francisco, on Monday, the day Zuckerberg turned 28. Zuckerberg’s company went public Friday, raising his wealth to a staggering $20 billion.

The wedding attendees went to Zuckerberg’s home believing they were attending a graduation celebration for Chan, but were happily surprised by the change of occasion.

“Everybody was shocked,” the guest said.

Zuckerberg designed his bride’s ring featuring “a very simple ruby,” the source said.

Food was served family-style and included dishes from the couple’s favorite Palo Alto sushi restaurant. The couple served Burdick Chocolate “mice” for desert — they had eaten the chocolates that are in the shape of mice on their very first date, People.com reported.

The couple were planning the wedding for months but wanted to wait until after Chan’s graduation, the guest said.

The wedding date wasn’t tied to the IPO, since that date was a “moving target,” the guest said.

The couple met at Harvard and have been together for more than nine years.