The billionaire British former owner of Premier League side Tottenham Hotspur, Joe Lewis, pleaded guilty to insider trading in a US federal court on Wednesday, a prosecutor said.

Lewis, 86, was accused of furnishing employees, including his private pilots, and lovers with insider information for years in a "brazen" scheme between 2013 and 2021 that raked in millions of dollars.

He was charged in the case six months ago, initially pleading not guilty with his lawyer calling the charges an "egregious error."

One of Lewis' companies has been ordered to pay $50 million in penalties in connection with the plea made before a US judge, the prosecutor said.

Lewis pled guilty to one count of conspiracy to commit securities fraud, which carries a maximum potential sentence of five years imprisonment, and two counts of securities fraud, which each carry a maximum potential sentence of 20 years in prison.

His sentence will be handed down at a date yet to be announced.

"While I possessed material non-public information about certain publicly traded companies, I agreed to make recommendations" to three other parties to buy that stock, Lewis told judge Jessica Clarke, Bloomberg News reported. 

"I knew at the time what I was doing was wrong and I'm so embarrassed." 

$6.2 bn fortune

Stock tips provided by Lewis included confidential information about upcoming favorable test results for biochemical companies, according to prosecutors.

"Lewis, on multiple occasions over the course of several years, misused and misappropriated this confidential information to provide stock tips to various individuals in his life, including his employees, romantic partners, and friends, as a way to provide them with compensation and gifts," the US Attorney for the Southern District of New York said in a statement. 

"These individuals, in turn, traded on the tips provided by Lewis for vast personal gain."

Prosecutors alleged that in 2019 Lewis lent his two pilots $500,000 each so that they could buy Mirati Therapeutics stock before the public release of the clinical results.

One of the pilots allegedly messaged a friend to buy the stock, telling them that he thought "the Boss has inside info."

Lewis is reported to be one of Britain's richest men with a fortune that Forbes puts at $6.2 billion, building his reputation as a currency speculator in the 1980s and early 1990s.

His holding company ENIC bought a controlling interest in Tottenham Hotspur Football Club in 2001 from then-owner Alan Sugar, another prominent British tycoon, for $22 million.

Lewis officially ceded control of the club last year, according to British financial records, and his stake was formally handed to a family trust.