The heir to South Korea's Samsung Group, Jay Y Lee appeared in a packed court today for the first day of arguments in the appeal of his five-year jail term for corruption.
In August, a lower court had found the 49-year-old guilty of bribing former president Park Geun-hye in exchange for help to strengthen his control over Samsung Electronics, one of the world's biggest technology companies.
Lee did not speak during the early proceedings apart from giving his birth date and address.
According to the August ruling, while Lee had not asked for Park's help directly, the fact that a 2015 merger of two Samsung affiliates helped Lee strengthen control over Samsung Electronics "implied" he was asking for the president's help to tighten his grip on the firm.
But the lower court's logic that Lee's actions "implied" solicitation for help from Park by providing financial support for the former president's close friend and confidante Choi Soon-sil was strongly contested by the defence.
The prosecution lodged a cross-appeal against the lower court ruling that found Lee innocent on some charges, contending that the court's decision to not acknowledge explicit solicitation for Park's help from Samsung despite the evidence found "did not make sense".
Prosecutors had asked judges in August to sentence him to 12 years in prison.
The two sides argued whether notebooks written by a former aide to the ousted president should have been admitted as evidence.
Prosecutors cited a spy case as they argued that notebooks, containing memos of Park's comments after meeting with Lee, showed the Samsung heir was guilty.
The Supreme Court had ruled in the case that a memo saved in a personal computer was sufficient to prove there had been contact between South Koreans and a pro-North Korean group, the prosecutors said.
Lee's lawyers argued against the admissibility of the notebooks as the memos were taken by a third person who was not present at the meeting between the former president and Lee.