$re = '/<(\S+)>\s*<(\S+)>\s*(?:"(.+)"|<(\S+)>).*./';
$str = '# started 2015-11-29T18:23:17Z
<http://dbpedia.org/resource/Bobcat_Company> <http://dbpedia.org/property/type> <http://dbpedia.org/resource/Subsidiary> .
<http://dbpedia.org/resource/Bobcat_Company> <http://dbpedia.org/property/website> <http://www.bobcat.com> .
<http://dbpedia.org/resource/Albedo> <http://dbpedia.org/property/colwidth> "30"^^<http://www.w3.org/2001/XMLSchema#integer> .
<http://dbpedia.org/resource/Anarchism> <http://dbpedia.org/property/voy> "no"@en .
<http://dbpedia.org/resource/Anarchism> <http://dbpedia.org/property/n> "no"@en .
<http://dbpedia.org/resource/Anarchism> <http://dbpedia.org/property/v> "no"@en .
<http://dbpedia.org/resource/Knight_Transportation> <http://dbpedia.org/property/keyPeople> "Kevin Knight"@en .
<http://dbpedia.org/resource/Knight_Transportation> <http://dbpedia.org/property/keyPeople> "Keith Knight"@en .
<http://dbpedia.org/resource/Knight_Transportation> <http://dbpedia.org/property/numEmployees> "4400"^^<http://www.w3.org/2001/XMLSchema#integer> .
<http://dbpedia.org/resource/Knight_Transportation> <http://dbpedia.org/property/industry> "motor transportation-trucking"@en .
<http://dbpedia.org/resource/Knight_Transportation> <http://dbpedia.org/property/products> "truckload shipping"@en .
';
preg_match($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