I'm wondering about this. It does look like a strike through but I believe the variety is listed on coppercoins as 1949S-1DO-001 and note the somewhat weak I and B there. http://www.coppercoins.com/lincoln/1949/1949s1do001ea.jpg This is the link to the variety ---> 1949S-1DO-001 here https://coppercoins.com/lincoln/diestate.php?date=1949&die_id=1949s1do001&die_state=eds (Cited from: https://www.cointalk.com/threads/1949-s-weak-ib.410195/#post-24902573)