1cent lincoln with no year defect coin

Thats is one interesting coin.  Somebody may have shaved off the date for fun or to make somebody think its a key-date or mint error.

I found a link to a forum with somebody who had the same problem.

Coin-Talk/penny with no-date 

My guess is that worn die + worn coin = partial date.

Or possibly there was a collar problem that led to a weak strike on the right (the rim appears to be wider).

I've got some old, worn Lincoln Cents where the LI in LIBERTY looks like it is missing.

But the main “defect” is most likely 80 to 100 years of wear.

Welcome to Numista. What originally caused the beginning of Liberty and the last digits of the date to be obliterated can be debated and we would only be guessing at what to attribute it to . It could also be explained as a simple grease blockage when minted for instance. What is certain is that it is heavily circulated and worn. Just a curiosity at this point. I do see what I think is the mintmark S below the date.