$re = '/PAYROLL\s+FIDELITY(*SKIP)(*F)|(FIDELITY(?!.*TITLE)(?!.*NATION)|INVEST)(?!.*PAYROLL)/m';
$str = 'INCOMING WIRE TRUST GS INVESTMENT
VANGUARD PAYROLL
PAYROLL FIDELITY
ACH CREDIT FIDELITY INVESTM-FIDELITY
ACH CREDIT FIDELITY INVESTM-FIDELITY
ACH DEBIT FIDELITY
ACH DEBIT FIDELITY
ACH CREDIT FIDELITY INVESTM-FIDELITY
';
preg_match_all($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