Is the ISO specification of PDF complete?

[Kopsky]

Hello, I have a question concerning programers who create the software that works with PDF. I need to know, whether you used the ISO specification of PDF to create the software, and whether it was usefull/helpfull and ultimatelly, whether it is possible to say, that the ISO specification is COMPLETE in the sense, that it (along with the programing skills independent of the format) contains sufficient information to create a program that could READ PDF. Comments on both ISO 32000 and ISO 19005 are welcome. Thank you for your time.

[mkl-public]

ISO 32000-2 ist not complete as it references numerous other specifications one also needs for a complete understanding of PDF. Some of these other specifications are even not maintained by institutions like ISO but by corporations like Adobe.
Furthermore, ISO 32000-2 has evolved from a long history of PDF References which Leonard Rosenthol (Senior Principal Architect at Adobe) once characterized as not normative in nature. Meanwhile much has been done to get rid of this not-normative heritage but there still are some remains of it.
Also it is very advisable to analyze lots of PDFs from many different sources to get a feel for how the specification commonly is interpreted.
And don't forget to keep an eye on the identified issues of the spec: https://github.com/pdf-association/pdf-issues

[asturio]

A nice comment from the duplication:

#1073 (comment)