Jason Holdings and former boss Jason Sim Chon Ang have been reprimanded for breaching Catalist rules.

The decision came after Jason Holdings announced late on Wednesday that Mr Sim had left his twin posts of chief executive and non-executive director on May 28.

The Singapore Exchange (SGX) said the group had materially overstated its revenue in its half-year financial results for the six months to 30 June, 2015.

Mr Sim had given instructions and authorised the inclusion of undelivered materials in progress claim billings to customers, resulting in the revenue overstatement.

In addition, he submitted falsified supporting documents to obtain short-term trade financing facilities from banks for its principal subsidiary, Jason Parquet Specialist (Singapore).

"SGX is of the view that Mr Sim, as the then executive director and CEO, failed to carry out his fiduciary duties and did not act in the interests of shareholders as a whole," said the SGX.

A 2016 report by EY highlighted a number of potential breaches of fiduciary duties in the management and administration of Jason Parquet.

The case has been referred to the authorities.

Back in 2016, the Commercial Affairs Department investigated Mr Sim and the Jason Parquet Specialist (Singapore) subsidiary regarding a possible offence under the penal code.

Mr Sim's travel documents were impounded in that year.

Jason Holdings said in an SGX filing on Wednesday: "With the liquidation of the company's wholly owned principal subsidiary, Jason Parquet Specialist (Singapore), Jason Sim Chon Ang is not able to play any role in the business and operations of the group as the company actively looks to inject new business into the group."

It added that Mr Sim was also "not involved" in the operations of the company's 60 per cent owned subsidiary, White Cubic.

As founder of Jason Holdings, Mr Sim oversaw the sale and marketing team of wholly owned subsidiary Jason Parquet Specialist (Singapore) before its liquidation on June 10, 2016.

Mr Sim said he intends to pursue business opportunities "outside Singapore", without providing specifics. His brother, Mr Sim Choon Joo, ceased to be a company director, also on May 28.

In its latest annual report, Jason Holdings said it is evaluating various new businesses for acquisition.

It was "actively looking for and negotiating with various potential parties" to inject new business into the company, said then non-executive chairman Lim Chwee Kim, who has since been redesignated executive chairman.

He added that the firm aimed to eventually submit a resumption proposal to the Singapore Exchange to have its stock resume trading on Catalist.