Why Office File Formats Still Lock In Institutions
20 Jul 2026
The pitch
A blog post from The Document Foundation argues that Microsoft's Office document formats—DOCX, XLSX, and PPTX—function less like neutral file types and more like a lock-in mechanism for governments, courts, schools, and public administrations. The formats are used by hundreds of millions of people worldwide, and the post traces how they came to dominate institutional record-keeping despite a standardization process that was, by the report's account, one of the most contested in ISO history.
How we got here
Before 2007, Microsoft Office relied on binary DOC and XLS formats. With Office 2007, Microsoft shifted to XML-based DOCX, XLSX, and PPTX. Microsoft then submitted these formats to international standardisation bodies, and they were approved as OOXML (Office Open XML). According to the report, national standards bodies flagged procedural irregularities and contested votes during that approval process.
OOXML itself splits into two variants: OOXML Transitional, the version that became widely used, and OOXML Strict, a cleaner variant that removes most problematic legacy elements. Microsoft Office has, per the report, always defaulted to Transitional rather than Strict—a detail the report flags as unexplained and worth further scrutiny.
By contrast, the Open Document Format (ODF) is described as an ISO standard with freely implementable, published specifications managed by a vendor-independent body. LibreOffice, called the leading open-source office suite, uses ODF natively.
The risks the report flags
Three concerns run through the piece:
- Institutional memory tied to one vendor. Governments archiving official records in a vendor-controlled format may be ceding long-term control over how that memory is stored and accessed.
- Inconsistent behavior across versions. Document features and formatting can behave differently—or fail—across different versions of Office, raising questions about whether today's records will remain accessible in the future.
- Structural dependency. Reliance on a single company's format standard could create long-term dependency for public institutions and courts that have few practical alternatives once adoption is entrenched.
What's still unclear
The report is explicit about several open questions it doesn't resolve: which specific procedural irregularities occurred during OOXML's ISO approval and which national bodies objected; what share of institutions currently use OOXML versus ODF; why Microsoft continues to default to Transitional over Strict; and whether there are documented cases of records becoming inaccessible due to format changes. There's also no data in the report on whether ODF adoption is growing or shrinking relative to OOXML, or on any active regulatory push toward open formats.
Why founders should care
For founders building document, productivity, or workflow tools—especially those selling into government, education, or enterprise—the report suggests a few things worth weighing, though with real uncertainty attached:
- Format choice may carry more than technical weight. If institutional buyers are increasingly wary of single-vendor lock-in, products built with ODF compatibility could plausibly have an edge in public-sector or compliance-sensitive sales conversations—though the report offers no adoption data to confirm this is currently a buying factor.
- Long-term portability could become a differentiator. Startups whose value proposition depends on document longevity or archival stability may want to consider how their format choices hold up against the kind of version-inconsistency risk the report describes, even though no concrete failure cases are cited.
- Reputational exposure is a possibility, not a certainty. The contested history of OOXML's standardization could matter to founders serving government or enterprise clients who care about compliance optics—but it's unclear from the report how much this history actually influences current procurement decisions.
Overall, the report frames this as a structural risk worth monitoring rather than an urgent crisis. Founders in this space may benefit from tracking whether any policy or regulatory shifts toward open formats materialize, since that could meaningfully change the calculus for product format support.