Holders of 36 per cent of voting shares have criticized the $36.26 per share bid or pledged to vote against the offer, saying the offer undervalues Cablevision.
Investors are at odds with CEO James Dolan over the value of assets including the Madison Square Garden network, which shows games from Cablevision's New York Knicks basketball team and New York Rangers hockey club. Cablevision also owns the cable-TV channel Fox Sports New York.
The two sports channels may be worth at least $2 billion, according to John Mansell, president of consulting firm John Mansell Associates.
The Dolans currently control a 20 percent stake in the company.
