Big Xstrata Shareholders Balk at Glencore Takeover LONDON - Glencore International's proposed takeover of the mining company Xstrata has the potential to create a global commodities giant, but the deal still needs to win shareholder support. On Tuesday, major investors in Xstrata spoke out against the acquisition, which would form a global diversified mining company with a market value of nearly $90 billion. "The deal means shareholders will be switching their portfolio from a high margin mining company to a larger business that also has a low margin sales and marketing unit," said Charles Cooper, a mining analyst at Oriel Securities in London. That's less attractive for some investors. Under the terms of the deal, Xstrata shareholders would receive 2.8 shares in Glencore for each of their existing shares in Xstrata. That represents a 15 percent premium on Xstrata's closing price last Wednesday, and values the company at nearly $62 billion. Since the takeover discussions were announced on Thursday, Xstrata's share price has risen almost 9 percent. Stock in Glencore has increased by nearly 5 percent in the same period. But the deal has not received the backing of some shareholders. David Cumming, head of equities at the British asset manager Standard Life Investments, said the proposed takeover undervalued Xstrata's assets and its future earnings potential. "Consequently, it is our intention to vote against the deal unless the merger terms for Xstrata shareholders are materially improved," Mr. Cumming said in a statement. Richard Buxton, head of British equities at the asset manager Schroders, also plans to vote against the deal, according to a company spokeswoman, Georgina Robertson. "This is a fabulous deal for Glencore, it's probably a great deal for the Xstrata management, but it's a poor deal for Xstrata's majority shareholders," Mr. Buxton told Reuters on Tuesday. The vocal opposition from some of Xstrata's shareholders, however, may not be enough to scupper the deal. The companies need the support of at least 75 percent of their individual shareholders to complete the transaction. Glencore already owns 34 percent of Xstrata. Standard Life holds just over 2 percent of Xstrata's stock, while Schroders owns roughly 1.45 percent, according to Bloomberg data. Mick Davis, Xstrata's chief executive, told investors on Tuesday that the deal should be completed by the end of the third quarter.