Billionaire heiress, 16, whose mom founded Flickr and dad founded Slack vanishes in San Francisco's notorious drug-riddled Tenderloin district as cops issue plea for help to find her

The heiress to a $1.6 billion tech fortune vanished from her mother's home in affluent Marin County, California, four days ago and is feared to be wandering the streets of a one of San Francisco's most drug-infested neighborhoods.  

Mint Butterfield is the only child of two of Silicon Valley's most well-known entrepreneurs, Slack co-founder Stewart Butterfield and Flickr founder Caterina Fake. 

According to a missing poster being plastered around the Bay Area, Mint was last seen on Sunday night at around 10pm in Bolinas, California, and was reported missing the following morning by her mother. 

The trouble teen, who is said of have battled addiction problems in the past, attends a private boarding school in Napa Valley. It's not clear how she would have traveled into downtown San Francisco. 

Marin County Sheriff's Office posted a missing flyer with Mint's picture to the social media platform Nextdoor on Tuesday.

Supervisor Matt Dorsey, a former representative of the Tenderloin, shared the flyer on X while revealing that Mint was thought to be in the area, which is synonymous with San Francisco's rampant crime and homeless problems. 

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

Mint's father, Stewart Butterfield(pictured), is co-founder of the messaging app Slack and is currently worth $1.6 billion. Slack was acquired by Salesforce in 2021 for $28 billion and Butterfield left the company in 2022

Mint's mother is Caterina Fake (pictured), who started the created the imaging service Flickr with her then partner, Butterfield. They sold the image-hosting website to Yahoo in 2005

Supervisor Matt Dorsey shared the flyer on X and said that Butterfield was now believed hanging around the Tenderloin - a seedy neighborhood in San Francisco (pictured) 

According to the San Francisco Standard, due to her previous problems, Mint is thought to be familiar with the Tenderloin-district. 

Police have yet to say whether she went there voluntarily on this occasion or if she has been kidnapped. 

When she was last seen, the teenager was last seen wearing a black sweatshirt, flannel pajama pants and black boots. She is described as having brown/reddish curly hair and pierced eyebrows. 

The Tenderloin is the center of the fentanyl crisis in San Francisco.

Squalid conditions, homelessness, crime, illegal drug trade, prostitution, liquor stores and strip clubs give the neighborhood a seedy reputation. 

Mint's father, Butterfield, is co-founder of the messaging app Slack and is currently worth $1.6 billion. Slack was acquired by Salesforce in 2021 for $28 billion and Butterfield left the company in 2022. 

Her mother is Caterina Fake, who started the created the imaging service Flickr with her then partner, Butterfield. They sold the image-hosting website to Yahoo in 2005. 

Since then, Fake has served on the board of several startups and is known as an angel investor in the tech world. 

Fake and Butterfield married in 2001 and remained together until 2007, when their daughter was born.

The Tenderloin, located in downtown San Francisco, has a reputation for crime and has some of the highest levels of homelessness and illicit activities in the crime-ridden city. It is the center of the Fentanyl Crisis in San Francisco

Squalid conditions, homelessness, crime, illegal drug trade, prostitution, liquor stores and strip clubs give the neighborhood a seedy reputation

Butterfield has since married Jen Rubio, co-founder of Away - an American luggage and travel accessories brand, and the pair have two young children together. 

Fake is now in a relationship with Jaiku co-founder, Jyri Engestrom, and the couple share three children between them. 

At the time of her disappearance, Mint was living with her mother and attending a private boarding school in the Napa area, according to the sheriff's office. 

In 2021, Butterfield purchased a $31.7 million mansion in Aspen, Colorado. The residence, which sits in the exclusive Five Trees neighborhood, sprawls over a five-acre estate overlooking the Castle Creek Valley. 

According to the listing, the property boasts a generous home gym, a state of the art home theatre, a second entertaining area with a bar and billiards table, a 500 bottle wine cellar, a tasting room, various separate gathering areas, six beautifully appointed en-suite bedrooms and a three-car garage.

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

Butterfield has since married Jen Rubio, co-founder of Away - an American luggage and travel accessories brand, and the pair have two young children together

In 2021, Butterfield purchased a $31.7 million mansion in Aspen, Colorado. The residence, which sits in the exclusive Five Trees neighborhood, sprawls over a five-acre estate overlooking the Castle Creek Valley

Butterfield also owns a $19 million home in San Francisco, which has seven bedrooms, eight bathrooms and sits in the posh Presidio Heights neighborhood

American journalist Yashar Ali pleaded with his followers on X for help in the search for Mint, saying 'I don’t ask for your help often, but I need it now…my friend’s 16-year-old has gone missing.

'Please spread this far and wide, and if you have any information about their whereabouts, call the number on this flyer.'

DailyMail.com has reached out to Butterfield and Fake for comment.