German potash miner K+S is considering replacing its bearer shares with registered shares, a move that would hamper sneak takeover approaches.

"We are looking into whether this makes sense for us," a company spokesman told Reuters on Monday, adding that no decision has been made yet.

By switching to registered shares, whose owners have to disclose their identity to the company, K+S would follow the example of fellow DAX members BASF and Adidas, who completed the swap this year.

Marc Gabriel, an analyst with Bankhaus Lampe, said registered shares could serve as a guard against unfriendly takeover approaches.

"This measure makes it more difficult for companies to sneak up on others with the aim of an outright takeover," he said.

Some market participants have speculated that mining giant BHP Billiton, which on Sunday scrapped its $39 billion bid for the world's biggest fertilizer supplier Potash Corp , could train its sights on K+S, but most analysts have dismissed the idea.

The mooted proposal to change its class of shares, first reported by daily Financial Times Deutschland on Monday, can be put to a shareholder vote at K+S's annual general meeting in May 2011 at the earliest.