Flaw in rehaut engraving of Sub

[noom]

Hi guys. Only recently noticed a possible flaw for the rehaut engraving on my 2013 116613LB (matte dial). I've attached 2 images, 1st is a closeup of the rehaut, 2nd is just a general shot of the dial, bezel, case.

Note the marks on the "O" and "L". Only these 2 letters are affected (located between the 4 and 5 o-clock side). Any idea if this is normal with regard to factory defects? Should I be concerned with the authenticity of the watch?

Thanks!

(note: I'm not the original owner. Watch was purchased preowned with full box and papers from a private seller.)