PDF/A is the archival form of PDF, ISO 19005: a PDF that embeds every font, runs no JavaScript, is never encrypted, and states in its metadata which part and level it claims. Nothing in the format makes a file read-only. The read mode comes from the viewer: Acrobat, for one, opens PDF/A files in a read mode, and a preference turns it off. You can edit a PDF/A file; whether it still meets PDF/A afterwards is a question only a validator answers.
Why does my PDF open read-only in PDF/A mode?
Because the viewer protects the claim. Adobe’s help for Acrobat says so: “When you open a PDF/A compliant document in PDF/A viewing mode, the document is opened in Read mode to prevent modification.” A message appears in the document message bar, and you cannot make changes or add comments. The same page notes that “Documents you scan to PDF are PDF/A-compliant.” That explains why a scan made in Acrobat can open this way.
This is not a password or a permission. PDF/A forbids encryption, in the Library of Congress’s words: “Encryption is disallowed.” A file that asks for a password, or says editing is restricted, is a different case, covered in PDF locked for editing.
How do you remove PDF/A read-only mode?
The mode is a preference in Acrobat, documented by Adobe:
- Open Preferences and choose the Documents category.
- Under PDF/A View Mode, set View Documents In PDF/A Mode to Never. The other setting, Only For PDF/A Documents, keeps the read mode.
- Close the file and open it again.
Adobe’s page adds: “If you turn off PDF/A mode, you can edit the document.” The preference changes nothing in the file: the file still claims PDF/A, and a colleague whose Acrobat keeps the mode on still sees it read-only. What people call “PDF/A protection” is this mode. To take the claim out of the file itself, see the Preflight fixup below.
How do you tell if a PDF is PDF/A?
A PDF/A file names its claim in two XMP metadata values, pdfaid:part and pdfaid:conformance. On a Mac, pdfinfo from Poppler (brew install poppler) prints the metadata, and a filter keeps the two values:
pdfinfo -meta file.pdf | grep -oE 'pdfaid:(part|conformance)(="[^"]*"|>[^<]*)'On a PDF/A-2b test file from the veraPDF corpus it printed, in our test of October 12, 2026:
pdfaid:part="2"
pdfaid:conformance="B"Part 2, level b: the file claims PDF/A-2b. On the demo invoice made for PDF Textfix’s screenshots, which has no metadata, it printed nothing.
In Acrobat and Reader, a file that claims a standard shows the Standards panel in the navigation pane; Adobe notes that “The Standards panel is present in all versions (Acrobat Professional, Standard, and even Reader).” Either way you have read a claim, not a test. Nothing stops a file from claiming PDF/A while breaking a rule; only a validator checks the rules.
Does editing a PDF/A file break its conformance?
It may, and the page will not show it. A harmless-looking change can break a rule: a font that is named but not embedded, a character with no Unicode value in a level u or level a file, structure tags that no longer match the text. The file keeps claiming PDF/A either way.
So an edited file’s conformance is unknown until it is validated. veraPDF, an open source validator, describes itself this way: “veraPDF is a purpose-built, open source, file-format validator covering all PDF/A and PDF/UA parts and conformance levels.” Acrobat Pro offers a conformance check of its own in the Standards panel: “To verify the standards conformance for the file, click Verify Conformance.”
How do you remove the PDF/A claim from a file?
When an edited file fails validation and you no longer need it to be PDF/A, take the claim out, so that viewers stop treating it as an archive copy. Acrobat Pro does this with a Preflight fixup. Adobe’s page describes it: “You can remove all PDF/X-, PDF/A-, or PDF/E-specific information, such as the output condition or the GTS_PDFX version key.” It also names the cases it is meant for: “This action is useful if a file has been modified, if you want to start over, or if an ICC profile increases the file size too much.”
The steps, as Adobe gives them:
- Choose All tools, then Use print production, then Preflight.
- In the Preflight dialog, choose PDF Standards from the Libraries list and open the Fixups tab.
- In the Document info and Metadata group, select the fixup for the standard: “For example, select Remove PDF/A Information.”
- Select Fix and save the file under a new name.
Keep the original. The fixed copy no longer promises a standard it does not meet.
What does PDF Textfix do with a PDF/A file?
PDF Textfix opens a PDF/A file for editing, with a banner above the pages that names the part and level, for example “PDF/A-2b document: characters missing from its fonts are always added with an embedded font.”
That banner states its rule for characters. A character the line’s font lacks comes from a fallback font, and in a PDF/A file that font is always embedded in the saved file, never one that is only named. The document’s own fonts are never changed; How fonts work inside a PDF and Embedded font explain the terms, and the manual’s section on fonts shows the marks.
When you save, PDF Textfix writes the whole file again, as What saving does to your PDF explains, and it keeps the file’s PDF/A identification and a line break before every endstream keyword. It neither validates files nor converts them to PDF/A. For a file that must stay PDF/A, use File > Save As (⇧⌘S) to keep the original, run veraPDF on the saved copy, and keep whichever passes.
The free version matters here. Free to try. Your first 5 line edits save clean. After that, saved files carry a watermark until you buy once. A PDF/A file that carries the watermark no longer conforms to PDF/A, so validate a copy saved without it. The manual explains the watermark, and pricing lists the one-time purchase.
Questions people ask about PDF/A files
Is PDF/A different from a normal PDF?
A PDF/A file is a normal PDF that follows extra rules and says so in its metadata. It opens like any other PDF. The differences are in what it leaves out, such as encryption, JavaScript and fonts that are only named. The PDF/A glossary entry lists the parts and levels.
Is removing PDF/A protection the same as removing a password?
No. PDF/A has no password and no encryption; the read mode is a setting of the viewer, which you turn off in its preferences. A file that asks for a password, or whose permissions forbid editing, is a different case, covered in PDF locked for editing.
Why did my scanned document open read-only?
Acrobat makes scans PDF/A-compliant, and with the PDF/A View Mode preference set to Only For PDF/A Documents it opens them in a read mode. Set the preference to Never. A scan is a picture of text, so changing its words also needs OCR; editing text in a scanned PDF explains what that can do.