Former media tycoon Jimmy Lai was on Monday convicted of all three national security-related charges he faced.

The verdict – delivered by High Court judges Esther Toh, Susana D'Almada Remedios and Alex Lee on Monday – followed a 156-day trial that concluded in August.

In their ruling detailed in an 855-page document, the judges said Lai was the “mastermind” behind the conspiracies, with his sole intent to “seek the downfall” of the ruling Communist Party.

“There’s no doubt that [the defendant] had harboured his resentment and hatred for the [People’s Republic of China] for many of his adult years,” Toh said on behalf of the bench.

It was evident that Lai's personal assistant Mark Simon was “working behind the scenes” to facilitate the Apple Daily founder’s meetings with senior US officials to lobby for hostile activities against local and mainland authorities, the court said.

The bench noted that the testimonies from prosecution witnesses were “solid and irrefutable”, while calling Lai’s evidence “contradictory, inconsistent, evasive and unreliable” at times.

Lai, who has been detained since late 2020, had pleaded not guilty to two charges of conspiracy to collude with foreign forces endangering national security and a count of conspiracy to print seditious publications.

He faces a maximum sentence of life in prison.

Three companies, namely Apple Daily Limited, Apple Daily Printing Limited and AD Internet Limited, were also convicted of conspiracy to collude with foreign forces and to publish seditious material.