I find pennys with lettering touching the coin edge or over running the edge. What is the cause. Any value added to these coins
if the edges of the coin gets worn down over time it can make one think that the letters are too high, as the rims have been lowered by wear. thus, Post Mint Damage pictures would help us confirm what we think. It's very difficult to know with 100% certainty what you are describing but it sounds like wear.
That also happens when the dies get worn out. As Clawcoins mentioned, we really can't tell without pictures. In either event, no added value.