$re = '/\.COM|(?<![A-Z]{2}) (?![A-Z]{2})|[.&,]| (?>)&/m';
$str = 'W. & J. JOHNSON LMT.COM
NORTH ROOF & WORKS CO. LTD.
DAVID DOE & CO., LIMITED
GEORGE TV & APPLIANCE LTD.
LOVE BROS. & OTHERS LTD.
A. B. & MICHAEL CLEAN CO. LTD.
C.M. & B.B. CLEANER INC.';
$subst = "";
$result = preg_replace($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