appreciate

Basic Incorporated was a publicly traded company primarily engaged in manufacturing chemical refractories for the steel industry. As early as 1965 or 1966 Combustion Engineering expressed interest in acquiring Basic but was deterred by antitrust concerns. In 1976 regulatory action removed the antitrust barrier and Combustion's strategic plan listed an objective to acquire Basic for thirty million dollars. Beginning in September 1976 Combustion representatives met and spoke by telephone with Basic officers and directors about a possible merger. During 1977 and 1978 Basic issued three public statements denying that merger negotiations were under way. On December 18 1978 Basic asked the New York Stock Exchange to suspend trading in its shares and announced it had been approached by another company concerning a merger. The next day Basic's board endorsed Combustion's offer of forty-six dollars per share. On December 20 1978 Basic publicly announced approval of Combustion's tender offer for all outstanding shares. Respondents are former Basic shareholders who sold their stock after Basic's October 21 1977 public statement and before the December 1978 trading suspension. Respondents brought a class action against Basic and its directors alleging that the three statements violated section 10(b) and Rule 10b-5 by misleading the market and causing sales at artificially depressed prices. The District Court certified the class under a presumption of reliance but granted summary judgment for the defendants on the ground that any misstatements were immaterial. The Court of Appeals for the Sixth Circuit affirmed class certification reversed the summary judgment and remanded the case. The Supreme Court granted certiorari.