$re = '/(\b([0-9]{10}|[0-9\s]{12})\b)/m';
$str = 'KINDLY AUTH FOR FUNDS
ACC 1469007967 (Number needs to be extracted)
KINDLY AUTH FOR FUNDS
ACC 146900796723423 **(Want to ignore this number)**
ACC NUMBER -1186 057 378 **(the number after - sign needs to be extracted)**
**1162792833** CHQ:104-R8856.00 AND (The number in ** needs to be extracted)';
preg_match_all($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