I ordered 6 HTU21D-F in order #PI46874. I’ve tested all of them and one of them appears to be faulty. Other units report a humidity level of 38.8%, except one, which reports a staggering 119%! Heres a picture of two of the units side by side.
The unit on the left is the faulty one. If you look closely, you can see that there is a small black area on the humidity sensor (the white area in the middle), which I think might be the reason for the behaviour. The temperature however, reports correctly, which further lends to the thinking that the damage to the white area being the cause.