An 89-year-old Wyoming billionaire is being sued in a California court on claims he subjected a female employee in her late 20s to hostile levels of sexual harassment and tried to get the woman and her husband to have orgies with him.
Madison Busby, a California woman who is 30, sued Hansjörg Wyss and his business, Halter Winery LLC, last month in a civil complaint filed in the Superior Court of California’s now San Luis Obispo branch.
Wyss unloaded tales of his sexual exploits on Busby, asked her and her then-boyfriend to have an orgy with him, subjected Busby to a video of a woman with whom he was having phone sex and grilled Busby about her sexual preferences, the lawsuit alleges.
The complaint asks for money damages, including punitive, pre-judgement and post-judgment interest, attorneys’ fees, case costs and any other “proper and just” relief.
Filed by Los-Angeles based attorney John Ly, the complaint accuses Wyss and the winery of sexual harassment and retaliation. It accuses the winery of wrongful termination and Wyss of inflicting emotional distress and sexual battery on Busby.
Originally from Switzerland, Wyss now lives in Teton County, Wyoming, the complaint says.
Wyss’ fortune stems from his 2012 sale of medical device manufacturer Synthes, which he founded, to Johnson & Johnson for $20.2 billion, Forbes reported. He holds stakes in biotech companies NovoCure and Molecular Partners, and has charitable foundations with assets of more than $2 billion, the news organization added.
The Saga
The problems started in 2019 when Busby met future husband Bryce Mullins, the complaint says. Mullins was already working for Wyss, who managed the California winery Halter Ranch.
When Wyss met Busby, he invited her and Mullins to cook with him at the ranch.
Wyss, then in his mid-80s and married, approached Busby as she cooked at the stove and groped her bottom, the lawsuit complaint alleges. He told her how good her bottom looked in the dress she was wearing.
The complaint says that a few nights later, Wyss suggested she wear that dress again because it looked “sexy” on her, and he asked Mullins whether he had any “sexy” photos of Busby on his phone that he could share with him.
Busby was “appalled and disgusted,” wrote Ly, her attorney. But she didn’t complain and hoped it was an isolated incident — especially since she’d developed strong feelings for Mullins and didn’t want to jeopardize his job.
By April 2020, Busby moved in with Mullins on Halter Ranch.
Wyss kept making sexual propositions and told of his sexual exploits “in graphic detail” to the couple, including his past and ongoing sexual affairs with women, the complaint alleges.
In the summer of 2020, Wyss and his wife wanted to renovate the Ridge House, which sat near Wyss’ estate.
Mullins and Busby lived at the Ridge house to supervise the renovation and Busby started working on the renovation and other design projects for Halter Ranch, says the document.
She became an official employee for the ranch and started reporting to Wyss in January 2021.

The Propositions
The complaint says that Wyss started propositioning Busby and Mullins to have sex with him while “trying to insert himself into their sex lives.”
The complaint lists a series of alleged misdeeds by Wyss, including that:
• Wyss told Busby she could join him in bed during a 2021 trip to Wyoming.
• Wyss told Busby how much he enjoyed having a threesome, even with another man, and he suggested that a “foursome” between the three of them and a woman named “Lori” would be fun.
• Wyss commented on Busby and Mullins’ sex life during a 2022 trip to Switzerland.
• Wyss described his affairs and said Americans are “too uptight” about affairs.
• Wyss told a story about how he and “Lori” went to a movie theater in Switzerland, met a male stranger, started oral sex with him and returned to Lori’s apartment for a threesome.
• Wyss subjected Busby to a live video of Lori while Wyss had phone sex with her.
• Wyss told Busby he wanted the couple to “FaceTime” Lori with him.
• Wyss shoved his iPad in Busby’s face and showed Lori, in sheer black lingerie, via FaceTime.
• Wyss asked the couple about their sexual preferences.
• Took off his clothes in front of Busby and Mullins and invited them to do the same.
The Fall
At some point, Wyss suffered a fall that kept him from walking and required Busby to care for him.
Also around this time, Mullins had some “promised ownership interest in the winery and estate” that Busby didn’t want to jeopardize for him by complaining, the lawsuit alleges.
But she soon sought treatment for the stress and received anxiety medication, it adds.
In the spring of 2022, Wyss told the couple: “If you ever went after me for sexual harassment, you would win,” says the complaint.
But his forays didn’t stop, it adds.
The Alleged Retaliation Campaign
In 2022 when Busby was pregnant, the complaint says she and Mullins tried to move into the Dubost House, a much smaller house on the estate that would have been too small to accommodate Wyss’ frequent visits.
But Wyss protested the move, telling the couple they’d have to start paying $1,650 in monthly rent, the complaint says.
Busby gave birth in February 2023. That same week, Wyss asked Busby to host him and his wife for a “surprise visit,” says the lawsuit.
The document says Busby returned to work in May 2023 after her maternity leave, and Wyss said the couple were both being “overpaid.”
Busby agreed to reduce her salary from $75,000 to $65,000 annually, says the complaint.
The document says Busby “was forced to resign” in July 2024.
Asked for comment at midday Friday, the person who answered the phone at Halter Winery hung up.
Wyss' media contact for the Halter Winery, Audrey Young, later sent a statement denying the allegations.
“The allegations in the complaint are not true and we intend to vigorously advance the facts that surround Mr. Mullins’ and Ms. Busby’s time at the winery and their departure," wrote Young in a Friday email statement. "For almost five years, starting in 2019, Mr. Mullins and his current wife voluntarily made themselves part of the Halter Winery community and took advantage of its owner’s generosity. This included deciding to become employees of the winery, choosing to live at the winery rent free for years, frequently traveling with the owner to Europe, the Caribbean and elsewhere at the owner’s expense, asking the owner and his wife to host their wedding party and inviting the owner to serve as Best Man.
"Through all these years, they never complained about the owner’s conduct, or simply declined to spend so much time with him, until after they voluntarily left their employment at the winery in 2024."
The Wyss Foundation, which is a philanthropic group Wyss launched as a lands conservation effort, gave the following statement: “The Wyss Foundation has no involvement with this matter. The organization’s charitable activities are totally separate from those of the Halter Ranch."
Clair McFarland can be reached at clair@cowboystatedaily.com.