2017 P Lincoln Shield Cent Pre Cud Die Crack?

datadragon, if the OP's coin and the listed coin, on COC (DC-1c-2017P-02), are in fact the same die, which I would find it hard to believe they are not, the OP's is definitely a later stage. You can easily see that the OP's "die chip" is longer and would have to be a later stage. I believe that Dearborn was referring to the fact that the die crack did not complete it's journey through the bust, back to the rim, which would have made it a pre-cud. JC, on COC, made changes a couple of years ago to the size a die chip had to be, in order for it to be considered an IDB but thought it odd that this is only considered a "die chip", I would have thought it would be large enough. Side by side pics below.

The below text from Cuds-on-Coins gives their information on the difference they use between a die chip and an interior die break. So using the actual size below might help to determine which it is if we are going by cuds-on-coins as the reference site, but yes it is interesting (depending on the actual size) that the similar coin on Cuds is listed as die chip only (starts with DC) unless its an error, and certainly in appearance differs from your typical die chip and is attached to die cracks. In the side by side image on this coin it appears longer as well. The prior error-ref link I added and here in this link as well below both mentioned that when none of the cracks reach the rim, the island of metal they radiate from is considered a freestanding retained interior die break not IDB so again just posting the info and try to apply it to this coin. Mike Diamond is here in this thread also so I'll just sit back and see what others have to say

Cuds-On-Coins:
Since voids left in the die face by natural fractures span an unbroken size continuum, there is no clear boundary between a "die chip" and an "interior die break". Any void encompassing an area of 4 square millimeters or more qualifies as an interior die break. Any void that covers less than 1 square millimeter is a die chip. In between is a gray area. Die chips are commonly encountered in all denominations. In Lincoln cents they include "BIE" errors, "plugged" 5's and 9's, and "bugs in the wheat ear".https://cuds-on-coins.com/retained-...-die-breaks/

I ended up acquiring this coin from the OP. And thought that the same thought's read in the discussion from others.
I would like to say that the coin indeed does rock slightly more so when the reverse is facing up and you touch the bottom of the reverse.

Here are my images of the coin as well.
(Idky the images when clicked on become so big, first time that's happened when reducing an image to the correct upload format)

Yea I'd agree I don't think it could be a bi facial grease strike as the obverse where the die break occurs on the reverse the weakness occurs in that exact same spot lines up with the crack. And the weakness keeps going till the coin is flush and struck. And that also matches up on the reverse as well. To perfect

I emailed images off to JC Stevens and he said it was later stage of the die chip listing. And that he'd list it as a RIDB Retained Interior Die Break. He stated he also seen horizontal movement as well on the obverse.

Can a retained interior die break also cause the weakness mike?
As there is some horizontal movement in the die break here it is slight.
Also the coin does rock slightly obverse facing down.
Curious of your thoughts I've been trying to research and look at RIDB to see if it can cause weakness on a coin on the same area obverse and reverse..