$re = '/([A-Z].[A-Z]\d+.SFR$)|([A-Z].[A-Z][0-9]\d+.SFR$)|([A-Z].[A-Z][0-9]\d+[A-Z].SFR$)|([A-Z].[A-Z]*[0-9]\d+ -.SFR$)/m';
$str = '1468 SFR-PHOTO_000-€
CAP- 1235 SFR1-
C-Z01434-SFR- PHOTO 000-
C-Z01468-SFR
SN- 1468 --SFR•+-CE•-•Request-for-approval
PAC-X0123 SFR-
B-00123•- Invoice for ABC
C-925303-SFR-
C-L25254-SFR
C-LP1122 SFR-
A-123456 SFR';
preg_match_all($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