(Bloomberg) -- Sika AG’s board, which opposes a bid by French competitor Cie de Saint-Gobain SA to seize control, curbed the voting rights of the founding family at a shareholder meeting Tuesday, prolonging a battle over the future of the Swiss building-materials maker.

A vote will take place later in the day at Sika’s annual meeting in Baar, Switzerland on whether to renew the board’s mandate for another year. The restriction will affect the Burkard family’s ability to elect directors, Chairman Paul Haelg said.

Sika’s board and the Burkards have clashed for more than a year after Saint-Gobain offered the heirs 2.75 billion Swiss francs ($2.9 billion), an 80 percent premium, for just their 16 percent stake with majority voting rights. By restricting the voting rights of the family to just 5 percent from 52 percent, directors opposed to the deal have remained in place to control the board and block the deal.

Sika’s chairman and other board members rejecting the Saint-Gobain offer will only accept that their seats are renewed Tuesday if they are all are re-elected.

The holding company of the Burkard family, Schenker-Winkler Holding, is proposing a new director to the board, Jacques Bischoff.

Management and minority investors gathered at the annual general meeting have opposed the deal since it was announced in December, 2014, saying it makes no strategic sense and is unfair to other shareholders left on the periphery of the Saint-Gobain offer.

The outcome is in the hands of a Swiss court, which is expected to decide before the end of the year on the legality of the board’s move to limit the family holding’s voting rights on decisions crucial to the future of the company.

To contact the reporter on this story: Alice Baghdjian in Zurich at To contact the editors responsible for this story: Tara Patel at, Andrew Noël

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