$re = '/-?(?<![\d.,])\d{1,3}(?:[,.]\d{3})*[.,]\d{2}(?![\d.])/';
$str = '\'2\', // no match
\'29.2\', // no match
\'2.48\',
\'8.06.16\', // no match
\'-2.41\',
\'-.54\', // no match
\'4.492\', // no match
\'4.194,32\',
\'39,299.39\',
\'329.382,39\',
\'-188.392,49\',
\'293.392,193\', // no match
\'-.492.183,33\', // no match
\'3.492.249,11\',
\'29.439.834,13\',
\'-392.492.492,43\'
8.06.16';
preg_match_all($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