If a client, former employer or competitor says your drawing came after theirs, you need to show when your CAD, BIM or Figma file existed. The dates your computer shows are easy to change, and cloud version history belongs to the platform. Here is what each kind of record is worth, and how to make one that can be checked later.
Short answer: CAD, BIM and Figma dates come from your own computer or the platform, so they are easy to dispute. To show a drawing or model existed before a date, export the exact files (DWG, RVT, IFC, .fig and PDF sets) and timestamp them with TimeBinder before you issue them. A TimeBind shows that the exact file existed no later than the recorded time and still matches its fingerprint. It doesn’t show who made it or what a court will make of it.
Disclosure: I’m Inna Hall, co-founder of TimeBinder, the file timestamping tool this guide uses. This page is general information, not legal advice.
Table of Contents
What you probably already have
- File system dates (created, modified). Useful as a hint, but they change when files are copied and can be set to anything with free tools.
- In-file metadata. Revit, Rhino, SketchUp and other tools store author and save details, but anyone with the file can edit or strip them.
- Cloud version history. Figma version history, Autodesk Docs or BIM 360 versions and Onshape’s history are strong day-to-day records. But they live in an account you may not control, history can be limited by plan, and they can be lost when a file is moved, duplicated or a workspace is closed.
- Emails and transmittals. A sent email with the drawing attached is good third-party evidence, if you keep the attachment exactly as sent.
Keep all of these. The gap is a record that’s independent of you and the platform, and that matches the exact file.
Why similarity isn’t enough
When designs look alike, the question is who had it first and whether one was copied from the other. Similar layouts often come from the same site constraints, codes and briefs. In Pearce v Ove Arup, the English Court of Appeal rejected a claim that a well-known building copied a student’s plans, because resemblance alone didn’t show copying. Dated working files from early in the project are what fill that gap.
What to freeze for each tool
- Figma: save a local copy (File → Save local copy, a .fig) and export a PDF of the key frames.
- Revit: save a detached copy of the .rvt at the milestone, plus the PDF sheet set you issued. Opening and saving a Revit model changes the file, so freeze a copy that nobody opens.
- Rhino, SketchUp, AutoCAD, SolidWorks, Fusion: the native file (.3dm, .skp, .dwg, .sldprt/.sldasm, or an exported archive) plus a PDF or image of the key views.
- Sketches and concept boards: the scans or photos, as originals.
Good moments to freeze: the first concept you show anyone, each issued stage (concept, developed design, tender), and anything sent to a client, consultant or manufacturer.
Step by step
Collect the frozen files. Put the native file and its PDF in one folder.
Zip big sets. One TimeBind covers up to 10 files. A Revit project with links or a large Figma export can be zipped and TimeBound as one file. Keep that exact zip, because the record matches the zip, not a re-zipped copy.
Open the app and select the files. Sign in at app.timebinder.io, start a TimeBind and drag the files in. Each file is hashed locally in your browser. Large model files are never uploaded, so size isn’t a problem.
Add a short Reference, for example Project 214, concept model as issued to client. The Reference and Details text are hashed into the record too, so keep them factual and leave out anything confidential.
Choose Pooled or ASAP. Pooled costs 1 Token and is usually recorded within 24 to 48 hours, and often sooner, depending on Bitcoin network activity. ASAP costs 3 Tokens and gets its own transaction (ASAP vs Pooled).
Download the Proof of Time Certificate and store it with the untouched files, plus a second copy somewhere else.
Later, anyone you choose can open the TimeBind, click Verify File and select the file. It is re-hashed in their browser and compared (verification explained). To see a file’s fingerprint first, the free SHA-256 file hash checker works without uploading anything.
Which plan fits
The free plan gives you 1 Token a month, which is one Pooled TimeBind of up to 10 files. That’s enough to date one milestone a month.
For several projects or stages a month, Essential is US$20 a month for 5 Tokens (5 Pooled, or 1 ASAP plus 2 Pooled). Expert is US$50 a month for 15 Tokens (15 Pooled or 5 ASAP), and unused Tokens roll over. Verification is free. See pricing.
What a timestamp does and doesn’t do
TimeBinder anchors each file’s SHA-256 fingerprint to Bitcoin and gives you a Proof of Time Certificate. That is verifiable evidence of when a file existed: it shows the file existed no later than the anchor date, and any later change to the file is detectable. An ASAP TimeBind can be checked directly on the Bitcoin blockchain without relying on TimeBinder; a Pooled TimeBind is verified through TimeBinder.
It doesn’t show who made the design or who owns it, it doesn’t stop copying, and it doesn’t cover a version you didn’t timestamp. Who owns drawings usually depends on your contract or employment terms. See architectural design timestamping and design file timestamping for routines.
Frequently Asked Questions
Is cloud version history enough?
Often it is for internal use. A separate timestamp helps when the platform account isn’t yours, history is limited, or you need a record someone outside can check.
My file is several GB. Does that matter?
No. Hashing happens in your browser and nothing is uploaded, so big files only take a little longer to hash.
Can I timestamp a file that has already been sent?
Yes, if you still have the exact copy that was sent. The record shows it existed no later than the day you TimeBind it.
Should I timestamp every save?
No. Freeze the milestones that matter: first concept, each issued stage, and anything you send outside the team.
Plan details were checked against timebinder.io/pricing on 28 October 2026.
