There’s a greater than one in ten chance that your latch key (your “Yale”) has a deep cut near the bow end. That’s no problem if the lock is working smoothly. However, if the lock is stiff or if you need to “jiggle” your key before it will start to turn, there’s a not insignificant risk that your key might snap off in the lock one day.

If your situation is the “jiggle” one, you could just try being careful (and sober); otherwise there isn’t much you can do except replace the cylinder and get good keys or sort out why the lock is stiff.