$re = '/([A-Z][a-z]+|[0-9]+|[A-Z]+?(?=[A-Z][a-z]|[0-9]|$))/m';
$str = 'ThisIsATest
TestTest
ATMMachine
NewATM
NewATMMachine
TestTest123123
NewATM09
New99ATM
NewATMMachine09
99ATM';
preg_match_all($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