Impala Platinum (Implats) has won a protracted battle for control of miner Royal Bafokeng Platinum (RBPlat) after bid rival Northam Platinum sold its stake.

Johannesburg-based Implats tabled an offer to acquire all outstanding RBPlat shares in January 2022, but was held back for over a year by Northam, whose intention to make a counter offer was terminated in April.

The sale of Northam's 34.5% holding will raise Implats's stake in the smaller platinum-group metals producer to 91%.

Shares in Northam, which said it will receive R9 billion in cash and about 30-million Implats shares for the transaction, were up 8.68% at 0713 GMT.

Implats spokesperson Johan Theron said the sale "represents the best possible outcome for all parties and our focus now shifts firmly to integrating the business and delivering value for our shareholders."

Implats now has a "clear path" to getting to 100% ownership of RBPlat, with its cash-and-shares offer open to other remaining investors, he added.

RBPlat has shallow and mechanised mines that both Northam and Implats wanted to gain control over.

RBPlat's mines are adjacent to Implats's own ageing, costly and deep-level shafts at the Rustenburg complex.

Citigroup analysts said the deal will remove an investor overhang and allows Implats to integrate RBPlat to its existing assets and fully realise synergies from it.

Northam said the stake sale could enable it to pay its first dividend, implement share buybacks and cut debt and offers the chance to significantly boost its balance sheet and liquidity position.

While Northam has sold the shares at a loss, the price it received for the stake is attractive due to the decline in platinum metal prices, RMB Morgan Stanley analysts said.

Northam had bought its RBPlat stake at an average price of R180 a share, but would receive R131 a share, based on Implats's latest share price.

"We believe Northam's balance sheet position has been an overhang into the (platinum price) downturn. This is now largely resolved," they said.