Author Information in Office Files
Office files can retain authors, company names, last modified by, templates, comments, tracked changes, hidden sheets, and links.
Office files such as Word, Excel, and PowerPoint files can retain author information.
Even if you do not write a name in the body text, personal names, company names, user names, template names, revision history, and comments may remain in the file's internal properties. When sharing materials anonymously, this becomes a strong clue.
This article organizes how author information in Office files relates to anonymity.
What author information is
Office files contain not only the body of the document, but also information about creation and editing.
| Information | Example | Anonymity risk |
|---|---|---|
| Author | personal name, OS user name | The person's name appears directly |
| Company name | organization name, department name | Affiliation becomes visible |
| Last modified by | name of the person who edited it | People involved become visible |
| Template | internal template name | Organization or department can be inferred |
| Comments | reviewer, internal note | People involved and decision process remain |
Office files are convenient formats for collaborative editing and review.
That convenience becomes a risk for anonymity.
Tracked changes and comments
Office documents can retain tracked changes and comments.
Even if you think you have cleaned up the body text, if comments contain real names, email addresses, internal conversations, or reasons for decisions, people involved can be identified from them.
| Feature | Information that remains | Caution |
|---|---|---|
| Tracked changes | who edited what | May remain even in the final version |
| Comments | internal notes and names | Delete before publishing |
| Hidden sheets | background data and notes | Be especially careful in Excel |
| Notes | presenter notes | Tend to remain in PowerPoint |
| Links | internal paths and cloud URLs | Organization information appears |
For Office files, looking only at the visible page is not enough.
Check review information and hidden information.
Converting to PDF does not make it safe
Converting an Office file to PDF does not necessarily make it safe.
The converted PDF may still contain a title, author, and creation software. Also, if you share the original Office file through another route, the author information remains there.
| Process | What may remain | What to check |
|---|---|---|
| PDF conversion | author and title | Check PDF properties |
| Print output | margins, headers, watermarks | Check the appearance |
| Collaborative editing | history and comments | Check the original file |
| Cloud sharing | owner name and edit history | Check how it appears at the sharing destination |
| Filename change | internal information remains | Do not judge by the name alone |
When preparing a publication copy, check both the original Office file and the converted PDF. However, if you upload the original file to an external conversion service or online document inspection service, the service may receive the document contents, author information, and access information. For high-risk materials, prioritize conversion and inspection in a local environment.
Check procedure
When handling Office files anonymously, create a publication copy.
| Step | What to check |
|---|---|
| 1 | Do not publish the original file directly |
| 2 | Create a publication copy |
| 3 | Check author, company name, and last modified by |
| 4 | Check comments, tracked changes, and hidden sheets |
| 5 | Check filename, folder name, and links |
| 6 | Recheck after converting to PDF or another format |
| 7 | Check whether the owner name appears at the upload destination |
For whistleblowing and reporting materials, there are situations where you should not decide how to handle the file alone.
You need to think about both evidentiary value and anonymity.
Typical situations where author information remains
Author information is inserted in places the person may not notice.
Documents created on a company-issued PC, materials created with a school account, files created under an OS user with a personal name, and collaboratively edited documents can contain information about the creation environment.
| Situation | Information likely to remain | Caution |
|---|---|---|
| Created on a company PC | company name, user name | Connects to the organization |
| Created with a school account | school name, email | Information about minors or students may appear |
| Collaborative editing | editor names, comments | Involves other people |
| Using a template | internal template name | Department or project becomes visible |
| Created on a personal PC | OS user name | A real name may be included |
Office files carry information about the environment where they were created.
If you publish anonymously, check information about the creation environment too.
Recheck after deletion
Even if you think you deleted author information, a name may remain somewhere else.
Check comments, tracked changes, hidden sheets, links, filenames, and properties after PDF conversion. Especially in Excel, it is important not to judge only by the sheets you can see.
| Check location | Information to look at |
|---|---|
| Document properties | author, company name, title |
| Comments | names, internal notes |
| Tracked changes | editors, changes |
| Hidden information | hidden sheets, notes |
| Converted PDF | author information on the PDF side |
Author information is not only a problem for the person publishing.
Names of co-editors, supervisors, colleagues, teachers, students, and family members may also remain. For anonymity, check not only whether your own name appears, but also whether names of people involved appear.
Be careful with Office files you receive
Author information in Office files is not only a problem with files you created yourself.
If you publish materials received from someone else as-is, you may send that person's name, organization name, and edit history outside. For anonymity, you need to protect not only your own information, but also information about providers and people involved.
| Received information | Risk |
|---|---|
| Author name | The provider becomes visible |
| Company name | Affiliated organization becomes visible |
| Comments | Internal conversations appear |
| Tracked changes | The order of people involved becomes visible |
| Filename | Project or department becomes visible |
Before publishing an Office file you received, create a publication copy and check the author information.
Separate the creation environment
For documents where anonymity matters, it is safer to separate the environment from the creation stage.
If you use an Office environment you use under your real name, a company-issued PC, a school account, or personal cloud storage, author information and sharer information are more likely to be inserted. You can delete it later, but the checking burden is smaller if you do not mix environments from the beginning.
| Environment | Likely problem | Way to think about it |
|---|---|---|
| Company PC | company name or user name is inserted | Do not use for anonymous publication |
| School account | school name or email remains | Separate it from personal activity |
| Personal cloud | owner name appears | Use a separate sharing path |
| Usual OS user | real-name user name is inserted | Prepare a publication environment |
| Collaborative editing | names of people involved remain | Organize into a publication copy |
Even if you separate the creation environment, you still need to check the body text and filename.
However, by not using a real-name environment from the start, you can reduce information that you might forget to remove later. For anonymity, what matters is not only deletion, but also designing things so they do not mix.
Summary
Office files can retain authors, company names, last modified by, comments, tracked changes, hidden sheets, and links.
For anonymity, check not only the body text, but also information inside the file.
Author information may remain even after conversion to PDF.
Before publishing, create a publication copy and check both the original file and the converted file.
For high-risk materials, it is also important to use a trusted consultation channel in order to balance evidentiary value and safety.
Related tools
ExifTool
An external resource related to this article. Open it only when it fits your situation and threat model.
Why it is listed: It can help with the article topic, but it is outside Anonymity Sense and should be checked before use.
URL : https://exiftool.org/
MAT2
An external resource related to this article. Open it only when it fits your situation and threat model.
Why it is listed: It can help with the article topic, but it is outside Anonymity Sense and should be checked before use.