"[1] Their decision cleared the way for class action to proceed against Halliburton over its alleged misrepresentation of facts material to the value of its stock price.

[3] The Court now allows defendants "to present evidence before a class is certified showing that the alleged fraud had no effect on the price" movements.

Even the foremost critics of the efficient-capital-markets hypothesis acknowledge that public information generally affects stock prices.

[11] Debates about the precise degree to which stock prices accurately reflect public information are thus largely beside the point.

price [of a stock] may be inaccurate does not detract from the fact that false statements affect it, and cause loss," which is "all that Basic requires.