Even the date, May 19, was significant: it was a mere day after Facebook's initial public stock offering, the culmination of Mr. Zuckerberg's life work since founding the social network in his Harvard dorm room in 2004. But the curiosity that lingered was not just about what designer's dress the bride chose to wear (Claire Pettibone) or how long it would take shareholders to sue Facebook for bungling its IPO (six days). Instead, people wanted to know: who was that princess bride who married Silicon Valley's crown prince?
Indeed, to anyone who still confuses Mr. Zuckerberg with the portrayal of him in "The Social Network," particularly the scene where his former girlfriend brushes him off (and the prospects of any future romance for young Mark seem dim), the very fact that he even had a longtime girlfriend must have come as something of a shock.
Ms. Chan, 27, unlike some of her equals in social status here (among them Mr. Zuckerberg's colorful sister Randi), eschews the Silicon Valley limelight. Recently graduated from the medical school at the University of California, San Francisco, she plans to become a pediatrician. (In that, she seems to be following in the path of other notable Silicon Valley spouses who have their own established careers, like Laurene Powell Jobs, the widow of Steve Jobs and an entrepreneur in her own right, and Anne Wojcicki, the wife of Google's Sergey Brin and a founder of 23andMe, a genetic testing firm.)
Ms. Chan guards her privacy and, so far, avoids speaking to the media unless it serves Mr. Zuckerberg's career. Though she has an active Facebook page (where her "interests" include "No on Prop 8" and Fage yogurt), she is rarely tagged in online party shots. She declined to be interviewed for this article.
"Priscilla doesn't need to be on the cover of a magazine," said Heidi Roizen, a venture capitalist and longtime Valley resident. "We are in a reality-star ecosystem. But there is a spectrum to this stuff, and some people take a more thoughtful approach."
One of the few people talking about the wedding, at least publicly, was Ms. Pettibone, thrust into the spotlight by Ms. Chan's choice of wedding dress.
Ms. Pettibone said she realized Ms. Chan was wearing her design after the designer's husband pointed it out in a photograph he saw of the new bride. "It's not our top seller," Ms. Pettibone said of the $4,700 dress, one of 40 in her bridal collection, in a phone interview. "But it's respectable."
All her dresses are made to order so, last week, Ms. Pettibone said she combed through her orders to see where the dress was sold. It was the Little White Dress boutique in Denver, and it was apparently bought by a third party.
Since the wedding, Ms. Pettibone said, traffic to her Web site has skyrocketed. And retailers are demanding samples to show prospective brides. "There is nothing like a celebrity bride to lift your profile," Ms. Pettibone said.
People who know Ms. Chan and agreed to speak, albeit without using their names for fear of offending her or Mr. Zuckerberg, said she is a quiet yet forceful presence who is protective of her new husband, whom she met in line for the bathroom at a fraternity party in 2003. Of their first encounter, Ms. Chan told The New Yorker in 2010, "He was this nerdy guy who was just a little bit out there," remembering his novelty beer glasses printed with a computer programming joke.
In Palo Alto, Ms. Chan is close to a handful of friends, including Jessica Vascellaro, a Wall Street Journal reporter, and her fiancé, Sam Lessin, a Facebook product manager; Jessica and Aaron Sittig, senior Facebook employees (Mr. Zuckerberg was best man at their Palm Springs, Calif., wedding); and Brittany Morin, who is married to Dave Morin, an early Facebook employee who left to become a founder of Path, a photo-sharing site.
The couple prefers dinner at home with friends to raucous parties, say people who know them. They dote on their Puli, a herding dog named Beast, which they frequently photograph and have created a page for on Facebook. Ms. Chan likes to cook (so says her Facebook page), and she is known among friends for her lemon ricotta pizza.
Most important, she has been accepted into the close-knit Zuckerberg family (Mark Zuckerberg has three sisters), from Dobbs Ferry, NY, but who have spread to Silicon Valley to work or visit. "They are building a new kind of dynasty," said a person close to the Zuckerbergs who declined to be named so as not to offend the family.
Ms. Chan was born on February 24, 1985, and moved with her family to Braintree, Mass., when she was a junior in high school, according to a recent article in The Patriot Ledger, a local newspaper. In 2003, she was named valedictorian at Quincy High School, where she had played tennis and won a science and technology challenge, and gave a graduation speech inspired by the Dr. Seuss book "Oh, the Places You'll Go."
Little has been written about Ms. Chan's Chinese-American family. But on Facebook, Dennis Chan has identified himself as the father of Priscilla and of two other daughters, Michelle and Elaine. Ms. Chan graduated from Harvard in 2007 with an undergraduate degree in biology before moving to Palo Alto to be with Mr. Zuckerberg, who had left Cambridge two years earlier. "She has always been a big part of the story of Facebook," said David Kirkpatrick, the author of "The Facebook Effect," which chronicled the company's meteoric rise. "It is unbelievably significant that Priscilla knew him before he became a billionaire."
In 2005, Mr. Zuckerberg was quoted in a profile of him in The Harvard Crimson talking to Ms. Chan and asking her if she wanted a job. "I'd love a job at Facebook," she replied, before offering Mr. Zuckerberg a Twizzler.
But unlike other classmates enamored of Mr. Zuckerberg, she stayed in school. "She was not particularly in Mark's thrall," Mr. Kirkpatrick said. "She just treats him like the guy she's in love with, not the same Mark Zuckerberg everyone else fell in love with."
Separated by 3,000 miles, Mr. Zuckerberg and Ms. Chan split up for awhile and Mr. Zuckerberg saw other women, including an undergraduate from the University of California, Berkeley, according to Mr. Kirkpatrick's book. When Ms. Chan reunited with her old beau in Silicon Valley in 2007, having been hired as a fourth- and fifth-grade science teacher at the Harker School, a private school in San Jose, she negotiated the terms of their getting back together, including the possibility of marriage, said a person who knows Ms. Chan. Mr. Zuckerberg was reluctant, said the person, contending that his youthful image was an asset to the company.
The couple agreed that they would not live together, but that Mr. Zuckerberg would spend at least 100 minutes of private time with Ms. Chan a week, as well as take her on at least one date, according to "The Facebook Effect." Indeed, Mr. Kirkpatrick reported that Mr. Zuckerberg once left a News Corp. corporate retreat, where he was a guest, explaining to the company's chief executive, Rupert Murdoch, that he was taking Ms. Chan to a movie. The couple also agreed to vacation for two weeks yearly overseas and have since visited Dubai, Mumbai and China. A friend said they were considering a trip to Peru this year.
In 2010, Ms. Chan moved into the rented house Mr. Zuckerberg was living in, in the College Terrace neighborhood of Palo Alto not far from Facebook's former headquarters. (They have since moved to the house where the wedding was held.)
Jessica Roth, a fourth generation cobbler who lives in College Terrace, said she used to see Mr. Zuckerberg and Ms. Chan walking to dinner at Palo Alto Sol, one of the restaurants that catered the couple's wedding. Ms. Chan even stopped in Ms. Roth's store, European Cobblery, once. "She was neutral, showed no emotion," Ms. Roth said. "She keeps to herself." One Halloween, though, Ms. Roth said, Ms. Chan dressed up as a pea pod and handed out candy to neighborhood children, including hers.
Among the issues that Ms. Chan seems to care about is that of donor organs, which is now one of Facebook's social causes. Mr. Zuckerberg told Robin Roberts, in an interview with "Good Morning America" earlier this year, that, while Ms. Chan was still in medical school, the couple would often talk at dinner about the desperately ill children she saw, and also the ones whose lives changed once they got an organ transplant. Mr. Zuckerberg called the transformation of their young lives "unbelievable."
Despite dating, and now being married to one of the richest men in the world, Ms. Chan is unlikely to amend her pragmatic sensibilities. The person who earlier commented on their relationship recounted the following story: One day, Mr. Zuckerberg's sister Randi was shopping with her future sister-in-law when Ms. Chan stopped to admire a pair of shoes that cost $600. Ms. Zuckerberg said, "You should get them, you have the money." Ms. Chan, instead, put the shoes back. "It's not my money," she replied.