 Cents with and without Brenner 's initials were struck at both Philadelphia and San Francisco in 1909 . Coins struck at Philadelphia bear no mintmark ; those struck at San Francisco were marked with an S. The 1909 @-@ S with Brenner 's initials ( commonly called the 1909 @-@ S VDB ) is the rarest Lincoln cent by date and mintmark , with only 484 @,@ 000 released for circulation . In 1911 , the Denver Mint began striking cents with the mintmark D , and in most years in the following decades , all three mints struck cents . In 1916 , Barber modified the design , causing Lincoln 's cheek and coat to appear less wrinkled . This modification was done to extend die life . 
