Ari Lauer, 61, outside counsel for the defunct California solar company DC Solar, was sentenced Monday to 11 years and five months in federal prison for helping orchestrate a $1 billion fraud scheme that deceived thousands of investors, federal prosecutors said. Lauer had pleaded guilty in October to 23 felony counts, including bank fraud and wire fraud, the U.S. Attorney’s Office said.

The sentencing marks the latest criminal penalty to emerge from one of the largest solar-energy frauds in U.S. history, in which DC Solar marketed mobile power units backed by phony inventories and fictitious lease contracts while repaying early investors with funds from newer ones.

A federal judge sentenced the outside counsel for defunct California solar firm DC Solar to 11 years and five months in prison Monday for his role in a $1 billion fraud scheme, the U.S. Attorney’s Office said.

Ari Lauer, 61, pleaded guilty in October to 23 felony counts, including bank fraud and wire fraud. U.S. Attorney Eric Grant said Lauer’s legal work was indispensable to the scheme’s operation. “Without the participation of Lauer, the DC Solar fraud scheme would never have been operational,” Grant said in a statement.

DC Solar, based in Benicia in the San Francisco Bay Area, marketed trailer-mounted mobile solar generator units between 2011 and 2018, touting them as emergency power sources for cellphone companies and lighting at sporting events. Executives told investors they could claim federal tax credits by purchasing the units and leasing them back to DC Solar, which would then provide them to other businesses.

In reality, prosecutors said, the company sold more generators than it ever produced, concealed the shortfall through phony financial statements and lease contracts, and repaid early investors with money collected from later ones — the hallmark structure of a Ponzi scheme. About 9,000 of the approximately 17,000 generators DC Solar claimed to have manufactured did not exist, according to prosecutors.

Warren Buffett’s Berkshire Hathaway Inc. was among the investors defrauded by the scheme, prosecutors said.

DC Solar founder Jeff Carpoff was sentenced in 2021 to 30 years in prison and ordered to pay $790.6 million in restitution for conspiracy to commit wire fraud and money laundering. Since then, five additional people — including Carpoff’s wife, Paulette Carpoff — have been sentenced to prison in connection with the fraud. Lauer’s conviction brings to at least seven the number of individuals to receive prison terms in the case.