
Incuse lines on the devices are often events that happen during circulation. The example Claude showed, show this MD on the right side of the coin. On the 'LIBERTY' on your coin were can see the same thing, but on the left side of LIBERTY. After the strike, the die movement, damaged the devices on LIBERTY damaging them a bit. This can see stronger on ones device and weaker on the same area.

The damage is not always the same. It is just the swing/bounce/movement of the die after the strike that makes this happen.
How to tell the difference? When you view the devices side by side, you can see the difference:

Note the image in the center. This is a normal strike. Note the contour light falling off both side the coin. The example on the left is showing a die that was hub doubled. We actually see two images, this is on the die. Thus they are called a doubled die because the hubbing of the die created two images. These are collectable. The unique thing is that each coin struck with that die will have that doubling effect. But note the last example on the left. This was struck by a normal die, note how the size is the same as normal, but certain areas are reduced from the machine movement after the strike creating a flattened area (damage on the coin). When you look at the affected areas on the coin, those areas are all the same color. No contour of light fading as it flows around the device. So this is a striking issue for the coin. Basically it was damaged, after the strike (
PSD) but it was damaged by the machine with uncontrolled die movement. When you look at a OBW (Original-Bank-Wrapped) roll, then you see other examples from the same machine leaving difference devices affected, but most of the time in different areas:

Note that different area on each strike were slightly different? This is caused by the machine and not from hub doubling (doubled die) that collectors are want to collect. This is common and easy to find. It confuses new collectors. So if the area you are seeing is, flat, shelf like looking, that reduces the size of the device, then it is machine damaged. If the devices are enlarged, showing a spread between the hubbing, then it maybe from a doubled die. Hope this helps.