Penny : Unlike all other coins the Lincoln cent has always had its mintmark on the obverse below the date to the right of Lincoln 's bust since its 1909 introduction .
All other coins had their mintmarks on the reverse until 1964 .
Penny : Unlike all other coins , which had their mintmarks on the reverse until 1964 , the Lincoln cent has always had its mintmark on the obverse below the date to the right of Lincoln 's bust since its 1909 introduction .