An Evaluation of Location Encoding Systems (2018)

The Open Location Code characters exclude easily confused character pairs. There are three discontinuities, at longitude 180 and at the north and south poles, where nearby locations can have very different codes, but due to the low populations in these areas we feel this is an acceptable limitation. Due to the way the codes are generated, latitudes are clipped to be greater than or equal to -90 and less than 90 degrees, making representing the exact location of the North Pole impossible although it can be very closely approximated.

Source: github.com