Sentence:  Thus , while it remains possible that the Babylonians and / or the Pythagoreans may perhaps have <WSD>had</WSD> the magic square of three before the Chinese did , more definite evidence will have to turn up from the Middle East or the Classical World before China can lose her claim to the earliest known magic square by more than a thousand years . 
Meaning of the word marked with <WSD> tags:  have or possess, either in a concrete or an abstract sense