Best results: Iranian Championship 2005, 1st; Marianske Lazne GM 2006, 2nd; 15th International fajr open tournament 2007, 1st; 17th Tehran Championship 2007, tied 1st; Iranian Championship 2008, 1st; Khashayar Mostafavi Kashani Cup 2010, tied 1st;
He represented his nation at the Chess Olympiads 2004-2010.
Mahjoob previously held the world record for simultaneous exhibition, which he set on August 13, 2009. He walked 18 hours and won 397 of the games, 90 draws and 13 loses.
Iranian chess Grandmaster (2007).