King has said the owner wants to sell his collection to Harvard.
"There are all sorts of really dodgy things about this," said David Gill, professor of archaeological heritage at University Campus Suffolk and author of the Looting Matters blog, which closely follows the illicit trade in antiquities. "This looks to me as if any sensible, responsible academic would keep their distance from it."
He cited the ongoing debate in academia over publishing articles about possibly dubiously obtained antiquities, thus potentially fueling the illicit market.
The Archaeological Institute of America, for example, won't publish articles in its journal announcing the discovery of antiquities without a proven provenance that were acquired after a UNESCO convention fighting the illicit trade went into effect in 1973.
Similarly, many American museums have adopted policies to no longer acquire antiquities without a provenance, after being slapped with successful efforts by countries like Italy to reclaim looted treasures.
Archaeologists also complain that the looting of antiquities removes them from their historical context, depriving scholars of a wealth of information.
However, AnneMarie Luijendijk, the Princeton University expert whom King consulted to authenticate the papyrus, said the fragment fit all the rules and criteria established by the International Association of Papyrologists. She noted that papyrus fragments frequently don't have a provenance, simply because so many were removed from Egypt before such issues were of concern.
She acknowledged the dilemma about buying such antiquities but said refraining from publishing articles about them is another matter.
"You wouldn't let an important new text go to waste," she said.
Hany Sadak, the director general of the Coptic Museum in Cairo, said the fragment's existence was unknown to Egypt's antiquities authorities until news articles this week.
"I personally think, as a researcher, that the paper is not authentic because it was, if it had been in Egypt before, we would have known of it and we would have heard of it before it left Egypt," he said.
Maggie Fick in Cairo contributed.
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