Yesterday, PPC reported a 9% increase in turnover for the year ended September to R6.8-billion.

In June, the commission launched a probe into an alleged cement industry cartel and raided the offices of producers PPC, Lafarge Industries South Africa, AfriSam Consortium and Natal Portland Cement Cimpor.

But PPC decided to co-operate with the commission, which yesterday announced it had granted the company corporate leniency in exchange for information relating to a cartel in the industry.

Chief executive Paul Stuiver was unable to reveal more but said the probe was "ongoing", with the company being asked to "not share further information on specific events, the timing or the people involved".

In its leniency application, PPC confirmed the existence of a cartel to divide markets among the four cement producers to maintain market share.

PPC held 46%, Lafarge 29.5%, AfriSam 29.5% and NPC 7% market share before 1996 when market allocation became illegal.

The commission said in a statement: "In exchange for immunity from prosecution PPC agreed to co-operate fully until the investigation and tribunal proceedings are finalised.

"In terms of the agreement reached PPC must also stop its involvement in cartel activity and refrain from submitting competition-sensitive information to the Cement and Concrete Institute."

The company could have faced a penalty of up to 10% of its annual turnover, which would amount to R680 million.