$re = '/STOP_DATE.+?VALUE\s*=\s*\"(.+?)\"/s';
$str = 'GROUP = TEMPORALINFORMATION
OBJECT = PRODUCTIONDATETIME
NUM_VAL = 1
VALUE = "2015-07-19T18:29:43Z"
END_OBJECT = PRODUCTIONDATETIME
OBJECT = START_DATE
NUM_VAL = 1
VALUE = "2015-07-11T20:17:22Z"
END_OBJECT = START_DATE
OBJECT = STOP_DATE
NUM_VAL = 1
VALUE = "2015-07-11T21:03:52Z"
END_OBJECT = STOP_DATE
END_GROUP = TEMPORALINFORMATION';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($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