Who owns your data?

As an example, TIFF of all things has proved to be an ongoing source of pain due to the joys of a) odd JPEG usage in older files, b) explicitly allowing for vendor extensions in the specification (annotations & highlighting that appear/disappear depending on the viewing app).

So far most of the issues of this type are work-aroundable, the issue is every time we hit a new scenario it takes time to investigate/find workarounds (if possible)/go back to the source (again if possible - discovery of an issue may be months/years after file creation).