KUALA LUMPUR (July 31): Hengyuan Refining Co Bhd, whose share price rose as much as 15.8% today, said it is unaware of any reason that could have caused the recent rally in its share price.

In its reply to an unusual market activity (UMA) query by Bursa Malaysia today, Hengyuan, a unit of Chinese refiner Shandong Hengyuan Petrochemical Co, said the board of directors, after making due inquiries, is not aware of any corporate development in relation to the group's business and affairs that has not been previously announced, or any rumour or report to account for the trading activity.

Hengyuan's share price rose to an intraday high of RM7.99 — a level not seen for more than three years — before closing 96 sen or 13.91% higher at RM7.86, making the counter the biggest stock gainer on Bursa. A total of 8.24 million shares changed hands.

The stock has been trading in a 52-week range of RM1.99 to RM7.99. Year to date, it has surged by 287.2% to its current level, giving it a market capitalisation of RM2.36 billion.

The company, formerly known as Shell Refining Co (Federation of Malaya) Bhd, is involved in the refining and manufacturing of petroleum products. Shell Refining became a subsidiary of Malaysia Hengyuan International Ltd after the latter acquired about 51% stake in the company for US$66.3 million last year.