$re = '/\b[A-Z][a-zA-Z0-9-]*(?:\s+[A-Z][a-zA-Z0-9-]*)*\b\.?(?!\s+[sS]egment)/';
$str = 'The Company\'s customers include, among others, Conner Peripherals Inc.("Conner"), Maxtor Corporation ("Maxtor"). The largest proportion of Applieds consolidated net sales and profitability has been and continues to be derived from sales of manufacturing equipment in the Silicon Systems segment to the global semiconductor industry.';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php