Open Source vs Proprietary File Formats: Why It Actually Matters

Here's a question nobody thinks about until it's too late: what happens to your files when the software that created them disappears?

If you've ever tried opening a really old Word document or a Photoshop file without Adobe's software, you know the frustration. Sometimes it works. Sometimes it kind of works. And sometimes you get digital gibberish.

The reason? File formats aren't all created equal. Some are open (anyone can read and write them), and some are proprietary (controlled by a single company). And that difference matters way more than you'd think.

What Makes a Format "Open" or "Proprietary"?

An open format has publicly documented specifications. Anyone can read the technical blueprint and build software that supports it. Think PDF, PNG, MP3, JPEG. These formats have standards bodies (like ISO) maintaining their specifications.

A proprietary format is controlled by a single company. The specifications are private. If you want to support it, you either reverse-engineer it (which can be legally messy) or license it from the owner. Examples: PSD (Adobe Photoshop), INDD (Adobe InDesign), older Microsoft Office formats before they opened up.

Some formats exist in a gray area. Microsoft's newer Office formats (DOCX, XLSX) are technically open standards, but Microsoft's implementation has features that other software struggles to replicate perfectly. So they're "open-ish."

The Real Consequences of Proprietary Formats

Let's talk about what actually happens when you rely on closed formats.

Vendor lock-in. Once you've built a workflow around proprietary formats, switching to a different tool becomes painful. Adobe knows this. Autodesk knows this. It's not an accident.

Your company uses InDesign files for all marketing materials? Good luck moving to Affinity Publisher or another alternative without converting everything first (and losing features in the process). That's the entire business model.

Compatibility nightmares. Ever sent a Pages document to someone using Windows? Or tried opening a modern DOCX file in LibreOffice and watched the formatting explode? Proprietary formats make collaboration harder when everyone isn't using the same software.

And if the company that owns the format decides to change it? You're along for the ride. Adobe updates PSD constantly. Sometimes old versions of Photoshop can't open newer files. You're forced to upgrade just to open your own work.

Digital obsolescence. This is the scary one. What happens when the company stops supporting the format? Or goes out of business entirely?

Remember WordPerfect? It was the dominant word processor in the early '90s. Now try opening a WordPerfect 5.1 file without hunting down ancient software or converters. Same with Lotus 1-2-3 spreadsheets, QuarkXPress documents, or PageMaker files.

Those companies didn't vanish overnight, but their formats became digital fossils. And if you stored important documents in those formats, you're stuck digging through archives or paying for specialized conversion services.

Why Companies Love Proprietary Formats

Look, companies aren't evil for using proprietary formats. (Well, mostly.) There are legitimate reasons.

Competitive advantage. If Adobe kept PSD fully open, competitors could replicate Photoshop's feature set perfectly. The closed format protects their business interests. Same reason Apple keeps Logic Pro's project files proprietary — they don't want Ableton or FL Studio importing them flawlessly.

Innovation speed. Open standards move slowly because committees have to agree on everything. Proprietary formats let companies experiment and add features faster without waiting for ISO approval.

Adobe added Smart Objects to PSD without needing anyone's permission. Microsoft introduced new Excel chart types without filing paperwork with standards bodies. Closed formats are nimble.

Licensing revenue. Some companies make money by licensing their format specifications. Dolby's audio formats, for instance. You want to support Dolby Atmos? You're paying for that privilege.

Open Formats and Long-Term Thinking

Open formats aren't perfect either, but they solve the big problem: longevity.

PDF is a fantastic example. Adobe invented it, but they released the specification publicly in 2008. Now it's an ISO standard (PDF/A for archival purposes). That means your PDFs will be readable in 50 years, even if Adobe ceases to exist. Libraries, governments, and researchers rely on this.

That's why archives use open formats. They're not thinking about next quarter — they're thinking about the next century.

PNG, JPEG, MP3 — all open standards. You can convert between image formats using dozens of tools because the specifications are public. Competition thrives, and users benefit.

And when open formats need updates, the community debates and refines them. Sometimes that's slow, but it also means bad ideas get filtered out before they're baked into the standard forever.

The Hybrid Approach: Best of Both Worlds?

Some software uses proprietary working formats but exports to open standards. This is actually a pretty smart compromise.

Final Cut Pro uses its own library format internally, but you can export to standard video codecs. Figma's files are stored in their cloud format, but you can export to SVG, PNG, or PDF. Same with Canva — proprietary working files, open export formats.

The downside? You lose some features in the export. Figma's auto-layout won't survive an SVG export. Photoshop's adjustment layers disappear when you export to PNG or JPEG. But at least your work is accessible outside the original tool.

What Should You Use?

Here's the practical advice: it depends on what you're doing and how long you need to keep it.

For short-term projects and active workflows: Use whatever tool fits best, even if it's proprietary. If you're a designer using Adobe every day, PSD files are fine. You're not archiving this stuff — you're working on it.

For long-term storage or sharing: Convert to open formats. PDFs for documents. PNG or JPEG for images. MP4 or WebM for video. Your future self will thank you.

For important records (legal, financial, research): Always use open formats. Governments and institutions have learned this the hard way. PDF/A is the gold standard for archival documents.

And if you're building software yourself? Default to open formats unless you have a really good reason not to. Your users will appreciate the flexibility, and you'll avoid becoming a cautionary tale when your startup pivots or shuts down.

The Future: More Open or More Closed?

It's honestly hard to say. The trend over the last decade has been toward more openness. Google pushes WebP and WebM. AV1 video codec is royalty-free and open. Even Microsoft opened up their Office formats (sort of).

But subscription models and cloud software are creating new forms of lock-in. Your files might technically be in an open format, but they're trapped inside a proprietary ecosystem (looking at you, Notion and Google Workspace).

The winner will probably be whatever balances innovation with interoperability. Formats that are open enough to be useful but differentiated enough to justify paying for premium tools.

In the meantime, be intentional about what formats you use. When you save a file, you're not just storing data — you're making a bet on whether you'll be able to open it in 5, 10, or 20 years.

Choose wisely.