Biotech CEO famous for spending millions to reverse age accused of walking out on ex after her breast cancer diagnosis and manipulating her in the spirit of 'radical transparency'

• A biotech CEO famous for trying to reverse his age was accused of walking out on a cancer-stricken partner.
• Ex-fiancée Taryn Southern alleged that Bryan Johnson emotionally and financially manipulated her.

A biotech CEO famous for spending millions to meticulously reverse his age was accused of walking out on an ex-fiancée after a breast cancer diagnosis and serially cheating on her.

According to a breach of contract lawsuit filed in Los Angeles in 2021, content creator and actress Taryn Southern alleged that entrepreneur Bryan Johnson obsessively controlled aspects of her personal and professional life. The pair were together between 2016 and 2019, according to the lawsuit, in a relationship where Johnson initially "swept Ms. Southern off her feet," only to emotionally and financially manipulate her to new lows.

Her lawsuit is seeking undisclosed damages for the emotional and financial damages she alleges Johnson caused. Johnson's representative did not respond to Insider's request for comment.

Johnson made a name for himself for initially selling a payment service Braintree to eBay for $800 million, and more recently gained attention for spending nearly $2 million on an intensive, experimental program that he hopes will reduce his biological age.

"It may seem something about diet, health, wellness, and anti-aging. Really, it's an exercise of imagining the future of being human," Johnson previously told Insider.

Part of his regimen includes a cocktail of up to 100 supplements, daily exercise, a mixture of experimental therapies, and a team of 30 medical experts closely tracking his progress and conducting, at times, intrusive tests such as regular colonoscopies.

While some of the measures, including a healthy diet and regular exercise, can slow the aging process, experts told Insider that they're skeptical the combination of interventions that Johnson's program involves can truly reverse one's age.

'Under the guise of radical transparency'

The pair met in 2016 and Southern moved into Johnson's Venice, Los Angeles, home within four months, according to court filings. Southern's lawsuit alleged that in the early days of their relationship, Johnson flew her to meet his wellness concierge to try to help her live "forever," but then left her at her most vulnerable.

The relationship quickly blended into a personal and professional one, where Johnson verbally promised to financially support Southern for life, her lawyers said.

Southern alleged that she signed a contract to work for Kernel, Johnson's company, assisting with, "the development and marketing of his personal brand, assistance with a documentary about the brain he hoped to finance, marketing efforts for his children's book, advice and insights on several venture investments," per court filings.

By 2018, the couple were engaged.

Southern's professional responsibilities for Johnson grew over time, and she stopped pursuing her own work, given Johnson's vow to support her, according to the suit. Her lawyers alleged that this was all part of a plan to make her financially dependent on him.

"Trickery, deceit, preying on Ms. Southern's physical and emotional weaknesses and financial dependence, and creating confusion and fear with his threats of legal action were major features of Johnson's scheme against Ms. Southern," Southern's attorneys wrote.

During their time at Johnson's Venice home, Southern alleged that the biotech CEO demanded that she "share a full list of her past sexual partners with him and describe the sexual acts that took place," and that over time, he serially cheated on her.

"He aggressively pursued and propositioned Ms. Southern's own friends and acquaintances – while other women were paid prostitutes or girls from 'Sugar Daddy" apps,' Southern's attorneys said in the suit. "He became obsessed with his sexual conquests and relaying the details of his triumphs to Ms. Southern under the guise of 'radical transparency and honesty.'"

Southern was increasingly asked to text him in encrypted messaging apps, to route her mail to a different PO box, and Johnson frequently used burner phones to communicate with her, citing his privacy concerns, per the lawsuit.

The separation

Around the time Southern learned of her breast cancer diagnosis and underwent chemotherapy treatment, things quickly unraveled, per the lawsuit.

"By October 2019, when he demanded that she move out of the home they had shared for three years – while she was in active treatment for Stage III breast cancer – she had no independent source of steady income to support her living and medical expenses," Southern's attorneys wrote in the suit.

Johnson repeatedly demanded that she move out, offering to pay her a $149,000 stipend, saying that she had become a "bad deal," and "net negative" for him, according to the lawsuit.

He asked for her to move out of his home, pushing for a separation and asking that she not mention it to her friends, Southern alleged, eventually pressuring her to sign the agreement without any legal representation in 2020.

Johnson's lawyers have denied the claims and said in filings that Southern is trying to extort him, and that since she worked for his company, her claims should be resolved in arbitration.

The biotech CEO's film about people with implantable brain interfaces, I AM HUMAN, was produced by Southern amid their relationship and then acrimonious split.

In a 2019 press release, Johnson advertised front and center that the film was a "female-directed and produced sci-fi documentary."