PDF xref tables
<p>A PDF file can contain multiple xref tables.
When you read a PDF file which has multiple xref tables and save it again. Should the newly saved file contain a single xref table or should all the original xref tables be written again to the file.
(--> indirect related question: when reading a PDF file, should the XREF tables and entries be stored internally in a single XREF table or table per table?)</p>

<p>Reading the 1.3 reference manual doesn't give me a clear answer.</p>