This lost boundary inscription was discovered in 1881 by Charles Clermont-Ganneau and his description of the episode helps to explain why scholars failed to locate it in the last century. From Archaeological Researches in Palestine 2:232:
In 1881, seven years after this incident, I had occasion to return to Palestine, and resumed, on my own account, the exploration of the neighbourhood of Gezer, which had been so unduly broken off. I had been persuaded all along that some more inscriptions must be in existence, similar to those I had discovered, marking out the boundary of the town towards the north-west. I started searching in this quarter, with the help of the fellahin, as on the previous occasion; it was not long before my labours were crowned with success, for about two or three hundred yards to the northwest of the first inscription I discovered some large characters, absolutely similar to the former, and cut into the face of a rounded rocky platform with almost perpendicular sides.
I have no record of these characters, but a rough sketch hurriedly made in my note book. I meant to go back and take a squeeze of them, fix the exact position of the inscription, and pursue my investigations on the spot; but, unfortunately, I was suddenly recalled to France, and was unable to carry out this intention. I regret this, for I am convinced that there still remains quite a series of these texts to be collected round about Gezer, I am certain that a search of this kind would not be unfruitful, and recommend it to future Palestine explorers.