The two billion pound acquisition of Dimension Data by Japanese communications firm NTT has been cast into doubt after South Africa's Financial Services Board (FSB) said it will investigate fluctuations in the company's share price immediately prior to its acquisition.
The regulator wants to determine whether or not unusually high volumes of share trading before the 15 July announcement were the result of a leak, or potential insider trading at DiData.
The firm had not officially informed shareholders that it was in talks with NTT until the announcement.
In its only statement on the matter DiData has said it supports the FSB's investigation.
Meanwhile, the ongoing acquisition was last week cleared by the EC, and is expected to wrap up on schedule by October.