Google's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In factGoogle's John Mueller said in a Google Webmaster Help thread that any of those third-party Google penalty checker tools are not valid. In fact