Shares in South African investment firm Venfin shot up by more than two percentage points yesterday on the back of rumours that the company was planning to sell its 15% stake in mobile group Vodacom to fellow shareholder Vodafone of the UK. Vodafone currently holds 35% of Vodacom, whilst SA’s Telkom has a majority 50% investment. Vodafone and Venfin declined to comment on the speculation.