rather than error. Middle one looks like a 'dry print' (lack of ink) - or even (judging by the inlay being slightly off color) that someone was a bit too vigorous cleaning the chip.
Been discussed before - these variations can occur in the same box of chips, let alone the same order or a re-order.
Ive never seen a red 'L', always black (IMO its actually very dark brown and your middle chip is missing the black ink to darken it)