Missing tech billionaires’ daughter, 16, is last seen at ferry port town 40 miles from San Francisco’s drug-riddled Tenderloin district amid fears she ran away from home at the weekend still in her pajamas before her mom raised the alarm

The missing teenage daughter of two prestigious Silicon Valley tycoons was spotted Monday at a ferry dock about 50 miles (80 kilometers) from her mother’s home in the San Francisco area, a family friend said.

Mint Butterfield, 16, disappeared from her mother’s home in affluent Bolinas on April 21. Her mother, Flickr founder Caterina Fake, reported her missing the next day.

According to the missing poster in the case, Mint was last seen in Bolinas on Sunday around 10 p.m. In a Facebook post, a family friend said the teen was spotted on April 23 in Larkspur Landing, a coastal community north of San Francisco.

Mint, heiress to a $1.6 billion fortune thanks in part to her father, Stewart Butterfield as the founder of the work messaging app Slack, is studying at a boarding school in Napa County.

He sold Slack to Salesforce in 2021 for $28 billion and formally left the company in 2022.

Adam Schermerhorn, a sergeant with the Marin County Sheriff’s Office, said Wednesday that Mint is believed to be in the infamous Tenderloin section of San Francisco, an area she has visited in the past.

She has a substance abuse problem, reports The everyday beast.

Mint Butterfield, the 16-year-old daughter of billionaire tech CEO Stewart Butterfield, has disappeared

A map showing the various locations Butterfield has been seen recently in the Bay Area

A map showing the various locations Butterfield has been seen recently in the Bay Area

Mint's father, Stewart Butterfield, moved back to his native Canada shortly after his daughter was born in 2007.

Mint’s father, Stewart Butterfield, moved back to his native Canada shortly after his daughter was born in 2007.

Her mother, Caterina Fake, has deep ties to Finland and visits the country regularly

Her mother, Caterina Fake, has deep ties to Finland and visits the country regularly

She is one and a half meters tall and weighs about 50 kilos. She was last seen wearing a black sweatshirt, flannel pajama pants and black boots.

Anyone with any information on Mint’s whereabouts is asked to contact the Marin County Sheriff’s Office. San Francisco police have not said whether they are involved in the search.

X-influencer and journalist Yashar Ali reposted Mint’s missing poster in a post that has been viewed 500,000 times. “I don’t often ask for your help but I need it now…my friend’s 16 year old is missing,” Ali wrote.

Prominent Bay Area politician Matt Dorsey also reposted the image.

Fake and Butterfield married in 2002 after meeting in 2000 in San Francisco. In 2004, the couple co-founded Flickr before selling it to Yahoo in 2005.

They divorced the same year Mint, their only child together, was born in 2007 for unknown reasons. After their split, he moved to Vancouver to start a new business.

‘I felt like my whole life was falling apart and I had to leave and go to India or something. It was a terrible period,” Butterfield says told Wired in 2014.

Butterfield got engaged to fellow tech CEO Jennifer Rubio in 2019. The couple has two children together.

Butterfield now has two children with his new partner, fellow tech CEO Jen Rubio, seen here earlier this month at a gala for the Metropolitan Museum of Art

Butterfield now has two children with his new partner, fellow tech CEO Jen Rubio, seen here earlier this month at a gala for the Metropolitan Museum of Art

Stewart Butterfield $19 million home in San Francisco, located in chic Presidio Heights

Stewart Butterfield’s $19 million home in San Francisco, located in chic Presidio Heights

Scenes from an average day in San Francisco's crime-ridden Tenderloin District

Scenes from an average day in San Francisco’s crime-ridden Tenderloin District

Authorities say Mint Butterfield is known to frequent the area

Authorities say Mint Butterfield is known to visit the area

Born in Pittsburgh, Fake has close ties to Finland. In 2020, she wrote in a post on X that her daughter “speaks fluent Finnish.” In 2015, Fake opened a coffee shop in Helsinki. According to Google, the restaurant is now permanently closed.

Her partner is Finnish tech entrepreneur Jyri Engestrom. In a 2015 interview with Wired, the couple described homeschooling the three children they shared. The piece notes that two of those children have since gone to public school.

In 2021, Butterfield purchased a $31.7 million mansion in Aspen, Colorado. Located in the exclusive Five Trees neighborhood, the residence extends across a five-acre estate overlooking the Castle Creek Valley.

According to the listing, the property features a lavish home gym, a state-of-the-art home theater, a second entertainment room with a bar and billiards table, a 500-bottle wine cellar, a tasting room, several separate gathering areas, six beautifully appointed en-suite bedrooms and a garage for three cars.

Butterfield also owns a $19 million home in San Francisco, which has seven bedrooms and eight bathrooms and is located in the upscale Presidio Heights neighborhood.

The properties are part of the $140 million real estate portfolio he co-owns with Rubio Wall Street Journal reports.

The couple bought at least five expensive homes in three states between January 2021 and August 2022.

The couple has an extensive real estate portfolio that spans three states and is worth approximately $140 million

The couple has an extensive real estate portfolio that spans three states and is worth approximately $140 million

Among their properties is a sprawling $31.7 million mansion in Aspen, Colorado, that spans over five acres

Among their properties is a sprawling $31.7 million mansion in Aspen, Colorado, that spans over five acres

Butterfield counts supermodel Karlie Kloss and husband Josh Kushner among his friends and photos show him and Rubio relaxing on the beach with the couple in 2018

Butterfield counts supermodel Karlie Kloss and husband Josh Kushner among his friends and photos show him and Rubio relaxing on the beach with the couple in 2018

They include two more properties in downtown Manhattan, a sprawling Hamptons mansion and a ranch designed by famed Japanese architect Tadao Ando in New Mexico.

The couple has an extensive art collection and Rubio is on the board of the Whitney Museum of American Art.

They are renowned philanthropists who previously donated $25 million to UNICEF.

Butterfield counts supermodel Karlie Kloss and husband Josh Kushner among his friends, and photos show him and Rubio relaxing on the beach with the couple in 2018.

Mint has two other half-siblings on her father’s side from his relationship with Rubio, a brother and a sister.