$re = '/(\w+)\s*=\s*([^;]*)/';
$str = 'FIRM_ID = MC0356400000; TAG = EQTV; CURR_CODE = SUR; CLIENT_CODE = FR334; LIMIT_KIND = 1; OPEN_BALANCE = 4822.84; OPEN_LIMIT = 0.00; LEVERAGE = 0;';
preg_match_all($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