$re = '/(?m)^([^|\r\n]*)[\r\n]*\|[\r\n]*([^|\r\n]*)[\r\n]*\|[\r\n]*([^|\r\n]*)[\r\n]*\|[\r\n]*/';
$str = 'Record 1|
Data|Commments|
Record 2|Some data|Notes|
Record 3|Data|
|
Record 4|Some data|Comments|
Record 5|Data|
|
Record 6|Some Data|Some Comments|';
$subst = "$1|$2|$3|\n";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
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