Bay Area Developer to Plead Guilty in $100 Million Scheme

Disgraced Sonoma real estate investor Ken Mattson is preparing to plead guilty to at least one count of wire fraud, signaling a major turn in a federal case that has shook Northern California’s commercial-industrial sector.

The plea, discussed Friday in an Oakland federal courtroom, could carry a maximum 20‑year prison sentence, Mercury News reported. Prosecutors have until May 8 to submit a proposed order to U.S. District Judge Jon Tigar, who will decide whether to accept the deal at a May 11 hearing.

Federal prosecutors accuse Mattson of running a “classic Ponzi scheme” that siphoned off more than $100 million from hundreds of investors in his projects. He allegedly sold interests in nonexistent real estate properties, traded properties among shell entities while funneling payouts to his own accounts and falsified records to conceal the theft.

Mattson, 64, was arrested by the FBI in May 2025 and initially pleaded not guilty to seven counts of wire fraud, plus money laundering and obstruction of justice. He was released on a $4 million bail.

Victims — many of whom were small investors or acquaintances from church circles — will be allowed to review the plea agreement and deliver statements at sentencing. The deal is expected to include financial restitution, though Mattson’s remaining assets are uncertain after his companies entered bankruptcy.

Mattson co‑founded LeFever Mattson with longtime partner Tim LeFever, later launching KS Mattson Partners with his wife, Stacy. Together, they amassed a $500 million California portfolio of more than 200 residential and commercial properties, roughly half in Sonoma County. Many of those sites now sit vacant or deteriorating.

Community group Wake Up Sonoma, formed in 2022 to oppose Mattson’s rapid property acquisitions, welcomed the plea as partial justice but warned against leniency. Both LeFever Mattson and KS Mattson Partners remain in bankruptcy, and the Mattsons themselves face eviction from their multimillion‑dollar Sonoma estate as creditors move in.

If the court approves the plea, sentencing will follow later this year — closing one of the region’s largest property fraud cases in decades.

– Joel Russell