The former CEO of the once ASX-listed Sirtex Medical, Gilman Wong, has pleaded guilty to insider trading.

The plea was announced today by corporate regulator ASIC, following an investigation into the sale of Sirtex shares by Mr Wong on October 26, 2016.

ASIC stated that while he was “in possession of inside information concerning Sirtex’s sales, Mr Wong sold 74,698 Sirtex shares” on that date.

Wong, who was CEO at Sirtex from 2005 to 2017, was charged with one count of insider trading under the Corporations Act on September 25 last year.

Under the Act, the maximum criminal penalty for an insider trading offence is 10 years in prison. Civil penalties can be applied up to $200,000 per contravention.

Historical data shows that in late October 2016, Sirtex shares were trading in the high-$20 range, before slumping to around $14 in early December after a surprise earnings downgrade.

Mr Wong’s sale amounted to more than a quarter of his holdings in the company, and he made an announcement in early November citing tax purposes as the reason for the transaction, according to the AFR.

Wong was then fired by the Sirtex board in January 2017 following the commission of an independent report into insider trading at the company.

Sirtex Medical was sold to Chinese buyer CDH Investments last year in a $2 billion deal.