Over the span of a week in 2015, a stock investor manipulated the share price of mainboard-listed dye maker China Fibretech, causing the price of the counter to plunge from $1.60 to as low as 54 cents.

Restaurateur Bruno Ludovic Soligny, 40, a naturalised Singapore citizen, was sentenced to 20 weeks' jail and fined $60,000 yesterday. He pleaded guilty to seven charges under the Securities and Futures Act, including four for market rigging.

He is appealing against the sentence, and was offered bail of $40,000.

Soligny, a substantial shareholder in China Fibretech, dumped his shares over three days between July 1 and July 8, 2015, with the intention to drive down the price.

A district court heard that he began buying China Fibretech shares in 2009 and increased his shareholding over the next few years.

In 2013, Soligny decided to use the trading accounts of his wife Linda Na Ching Ching to "roll over" his purchases as he did not have the means to pay for them.

He would buy the shares in his own securities account and when the deadline to make payment approached, he would transfer the shares to one of his wife's accounts.

When the new settlement date approached for his wife's account, he would transfer those shares back to his own account.

This process was repeated between July 1, 2013 and Sept 30, 2015, making up more than 30 per cent of the trades in the company.

By October 2014, he held more than 5 per cent of the company. His shareholding increased to 6.11 per cent in March 2015.

Investigations showed he had been dissatisfied with the company's management since late 2014 and was further aggrieved by a share consolidation exercise that reduced the liquidity of the shares.

Liquidity refers to the ease by which shares can be traded without affecting the asset's price.

Between May and June 2015, he repeatedly wrote to the Singapore Exchange (SGX) and the Securities Investors Association (Singapore), or Sias, to air his grievances.

On the afternoon of July 1, 2015, he began dumping his shares. The price of the counter dropped from around $1.60 to $1.125 at 4.46pm.

At 4.57pm, SGX queried China Fibretech about the unusual price movements but the company said it was not aware of any reasons to explain the trading activities.

The following morning, SGX issued a "trade with caution" notice in relation to the counter.

On July 7, Soligny began dumping shares again, driving the price down to 70 cents from its last traded price of $1.03.

The trades over the two days made up more than 99 per cent of the total trades in China Fibretech .

On July 8, he continued to sell his shares, causing the price to slump to as low as 54 cents.

He stopped after SGX contacted him and agreed to meet him together with the company's management and Sias.

Later that month, Soligny decided to push the share price up.

On July 16, he traded shares between his own accounts and those of his wife, inflating the price from 80 cents to $1.03.

On Aug 31, he again carried out a series of matching trades, driving the price up from 77 cents to $1.09.

Trading in China Fibretech shares was suspended on Nov 30, 2015. It resumed on Sept 28 last year under the new name of Raffles Infrastructure Holdings.