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Dec 14 (Reuters) - South Africa's Rand Merchant Investment Holdings Ltd said it bought a 30 percent stake in UK insurer Hastings Group Holdings Plc in a deal worth between 487.3 million and 499.5 million pounds ($634.61 million).
Rand Merchant offered between 248 pence and 255 pence per Hastings share, the top end of which represents a 15 percent premium to the stock's Tuesday close.
Hastings' stock was up 4.9 percent at 232.3 pence at 1502 GMT on the London Stock Exchange on Wednesday.
Rand Merchant said it bought the stake from Goldman Sachs and founder shareholders.
As part of the deal, which makes the South African investment firm the biggest shareholder in Hastings, Rand Merchant's Chief Executive Herman Bossman has been named to Hastings' board.
The stake sale to Rand Merchant comes merely months after holding vehicle Hastings' Investco, Neil Utley, Utley Family Charitable Trust and Richard Brewster sold about 45 million shares, or about 6.8 percent of the company's then issued share capital.
Hastings said it welcomed Rand Merchant's investment, which both firms have capped at 29.9 percent. ($1 = 0.7871 pounds) (Reporting by Vidya L Nathan in Bengaluru; Editing by Martina D'Couto)