"I don't know if we will ever declare a victory but we are at the end of stage one," CEO Neal Froneman told Reuters.
The company implemented a strategy in 2017 to rid its operations of illegal miners, which it believed were assisted by employees who gave them access or food during their time underground.
The company told the wire service that the estimated thousands of illegal miners had been reduced to 40-50 people at its Kloof and Driefontein operations.
Froneman said the company would need to maintain its costly vigilance to prevent illegal miners returning, Reuters reported.
Shares in the company closed up 2.37% yesterday to ZAR1168, a little higher than last week's 12-month low of 1071 after the company flagged then reported an attributable loss of US$333 million for 2017.
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