In order to make the Bull available for research and translation, condition issues needed to be addressed. The document was brought to paper conservators at the Conservation Center for Art and Historic Artifacts in Philadelphia for assessment and treatment.
The most significant issue was that the parchment had been tightly folded for many years, so that it could not be unfolded without risking damage. This made it impossible to view the full text of the document and learn about its history.
Conservators used a process called humidification, in which moisture is carefully introduced to the parchment in order to relax it and increase its flexibility. Using this technique, the parchment could be flattened without damage.
In order to mend the hole, conservators used mulberry paper, a type of Japanese paper with long, strong fibers and neutral PH. The paper was toned to match the document and applied with special archival adhesives. Repairs like this are designed to be reversible with the proper techniques, so that the document can be restored to its original state if necessary.