Gaborone: DE BEERS Consolidated Mines (DBCM) is close to completing a probe into the leak of sensitive data about its pricing of rough diamonds and details of sales to South African clients, company CEO Philip Barton has said.

There was a leak of the De Beers price book, which contains diamond valuation data and customer details and invoices in South Africa, and was drawn up after a sale that the company calls a sight. The report was confidential and sent to the state-run diamond regulator.

Diamond Intelligence Briefs diamond analyst Chaim Evan Zohar said in April he had copies of highly detailed data of output from DBCM, the South African mining arm of De Beers, an Anglo American subsidiary. This data included the categories, qualities, carat sizes and prices. There were also customer invoices detailing sales.

“The investigations are nearing their conclusion,” Mr. Barton said on Tuesday. “We’ve done our internal investigations and we’ve had external companies helping us … to make sure the leak is not coming from within.” De Beers strongly believes the leak did not come from its staff.

The South African Diamond and Precious Metals Regulator is conducting its own probe into the leak of the price book, which Mr. Zohar described as “perhaps the most valuable and best protected trade secret of De Beers”.

Mr. Barton said that the regulator had been helpful. “Under then minister (of mineral resources) Susan Shabangu, it took immediate action and has been, from our point of view, very responsible and proactive around this matter.”

He declined to give a time frame for when the investigation would be concluded or what steps would be taken.