The Problem With Building Evidence for CAD & Engineering Drawings
Engineering drawings represent months of work. Design theft by contractors, partners, or competitors is common. Patent applications need proof of invention date.
In legal proceedings, gaps in evidence trails create doubt. Continuous timestamping eliminates those gaps.
For architects, engineers, product designers, manufacturers, this is not a theoretical risk — it is a daily reality. An engineering firm shares preliminary designs with a manufacturer. The manufacturer takes the designs to a competitor for cheaper production. Timestamped originals prove the firm created the designs.
How TimeProof Solves This
When you timestamp cad & engineering drawings with TimeProof, TimeProof uses client-side file hashing (SHA-256). That 64-character value is the unique fingerprint for the exact version you selected, and if even one byte changes, the hash changes too. Your file never leaves your device.
TimeProof proves file existence by anchoring file hashes to the Polygon blockchain. The blockchain records the hash, timestamp, and transaction ID permanently, so anyone can verify the record independently on Polygonscan without relying on editable metadata or a vendor-controlled database.
For architects, engineers, product designers, manufacturers, that means creates a chronological chain of timestamped evidence that holds up under scrutiny. timestamping CAD files at design milestones creates a verifiable engineering timeline for patent filings, contract disputes, and design ownership claims.
Specific to CAD & Engineering Drawings
Timestamping CAD files at design milestones creates a verifiable engineering timeline for patent filings, contract disputes, and design ownership claims. Common file formats include DWG, DXF, STEP, IGES, 3DM, RVT, and TimeProof handles all of them. Whether you are using AutoCAD, SolidWorks, Revit, Rhino, Fusion 360, the workflow is the same.
The Metadata Problem
Many people assume file metadata is sufficient proof. It is not.
CAD file metadata shows modification dates but these reset when files are copied between systems. BIM model history is internal to the platform.
A blockchain timestamp is independent of your file’s metadata. It is stored on the public Polygon blockchain, which no one controls. Even if every byte of metadata is stripped, your timestamp remains permanent and verifiable.
Step-by-Step: Building Evidence for Your CAD & Engineering Drawings
Timestamp each operative file as it enters the record so later reviewers see a dated evidence trail instead of one retroactively assembled bundle. Best used at each risk-critical milestone when a new file becomes part of the operative record. Common files in this workflow include evidence bundles, source documents, and support exports. Typical reviewers or counterparties include counsel, investigators, and reviewers.
- Identify the document, export, or media file that now matters to the record.
- Timestamp that exact file at the time it becomes operative.
- Store the certificate and Polygonscan link with matter notes, claim logs, or review packets.
- Repeat for later supporting files so the trail reflects the chronology instead of relying on one final bundle.
Step 1: Select your file. Open TimeProof and drag your file onto the upload area. TimeProof accepts DWG, DXF, STEP, IGES, 3DM, RVT and every other file format. The SHA-256 hash is computed entirely in your browser — your file never leaves your computer.
Step 2: Choose your timestamp type. Use scheduled timestamps for 1 credit per file, or use verified instant timestamps for 2 credits per file when immediate anchoring matters. Both produce permanent, identical proof.
Step 3: Confirm and anchor. Click the timestamp button. TimeProof computes the SHA-256 hash locally, sends it to the Polygon blockchain smart contract, and returns your proof. You pay zero gas fees — TimeProof covers all blockchain costs.
Step 4: Download your proof. You receive a PDF certificate and a direct link to the blockchain transaction on Polygonscan. Verified instant timestamps add a verified identity badge, and Legal-Grade adds the Courtroom-Ready PDF, JSON metadata, JWS identity attestation, and Complete Evidence ZIP.
Step 5: Add Legal-Grade if needed. Legal-Grade is a verified per-batch upgrade. Starter and Pro charge 50 credits for up to 25 files, then +2 credits per file after 25. Business charges 25 credits for up to 25 files, then +1 credit per file after 25. Enterprise includes Legal-Grade. It adds the Courtroom-Ready PDF, JSON metadata, JWS identity attestation, and Complete Evidence ZIP.
What You Receive
Every TimeProof timestamp for cad & engineering drawings includes:
- PDF certificate - a readable proof document for the exact cad & engineering drawings you timestamped, ready to keep with the project or share when timing becomes disputed.
- Polygonscan link - direct public verification of the on-chain hash, timestamp, and transaction.
Verified instant timestamps also include: 3. Verified identity badge - the certificate shows the timestamp was created by a verified account, which is useful when delivery timing, authorship, or submitter identity may later matter.
With the Legal-Grade upgrade, you also receive the core evidence-package components documented by TimeProof: PDF, JSON, JWS identity attestation, and a ZIP bundle.
- Courtroom-Ready PDF - a presentation-ready evidence certificate for disputes around build a tamper-proof evidence trail, payment, originality, or formal review.
- JSON Metadata - machine-readable timestamp data for technical teams, audit trails, or structured evidence review.
- Identity Attestation (JWS) - a signed proof that ties the timestamp to a verified identity and can be verified through /.well-known/jwks.json.
- Complete Evidence ZIP - one bundle containing the Courtroom-Ready PDF, JSON Metadata, Identity Attestation (JWS), and supporting proof materials so counsel, clients, or reviewers can inspect the complete record in one place.
Why Blockchain vs Other Methods
TimeProof uses Polygon because architects, engineers, product designers, manufacturers need proof that is fast to create, inexpensive to repeat, and easy for third parties to verify.
TimeProof proves file existence by anchoring file hashes to the Polygon blockchain. This gives reviewers a public record they can inspect independently on Polygonscan.
- Speed: about 2-second block times when verified instant proof matters.
- Cost: users do not buy crypto or manage gas fees because TimeProof covers blockchain costs.
- Public verification: counterparties, clients, auditors, or counsel can inspect the record independently on Polygonscan.
- Security: the record sits on a public, tamper-resistant network aligned with Ethereum.
- Permanence: the timestamp remains verifiable long after the cad & engineering drawings have been shared, reposted, or challenged.
Real-World Scenario
A file set is credible in isolation, but later scrutiny turns timing gaps into a challenge about when each supporting record actually entered the matter. The files at issue are often evidence bundles, source documents, and support exports. Typical reviewers or counterparties include counsel, investigators, and reviewers.
An engineering firm shares preliminary designs with a manufacturer. The manufacturer takes the designs to a competitor for cheaper production. Timestamped originals prove the firm created the designs.
A reviewer questions when a file entered the record, the other side claims the evidence trail was assembled retroactively, or supporting exhibits lack a defensible chronology. A sequence of timestamps turns isolated files into a dated evidence trail, making late-stage assembly claims harder to sustain.
Related Comparisons
These comparisons help you measure this proof path against common alternatives that solve part of the problem but not the full timing-and-integrity chain.
- TimeProof vs Email Proof: Compare ad hoc email paper trails with file-specific timestamps that preserve chronology as the record develops.
- TimeProof vs Registered Mail: See why mailing records do not create the same digital-file evidence trail when exhibits change over time.
- TimeProof vs Manual SHA256: Compare isolated checksum practices with a workflow built for repeated, independently reviewable milestones.
Related Guides
Use these related pages to go deeper on the legal, verification, or pricing context behind this workflow.
- Preserve Chain of Custody for Legal Documents: Add custody-aware handling when the evidence trail will be reviewed across multiple people or formal handoffs.
- Create Legal Evidence for Legal Documents: Escalate a chronological record into a formal evidence package when the matter is moving toward legal or regulatory scrutiny.
- Pricing: Review the current credit model for repeated milestone timestamping across longer matters.
Pricing
TimeProof uses one unified credit balance, so you can build evidence for cad & engineering drawings as part of normal work instead of waiting for a dispute.
- Scheduled timestamps: 1 credit per file - available to everyone, with proof available within 6 hours.
- Instant timestamps: 2 credits per file - available to verified subscribers, anchored in about 2 seconds.
- Legal-Grade: Starter and Pro: 50 credits up to 25 files, then +2/file. Business: 25 credits up to 25 files, then +1/file. Enterprise: included.
One-time packs start at $15 for 100 credits. Verified monthly plans start at $19/month and include identity verification for instant timestamps and Legal-Grade.
Timestamp major design milestones using 1 scheduled credit per file. A 30-file phase package would use 30 credits. Use scheduled timestamps for routine protection, verified instant timestamps when timing must be immediate, and Legal-Grade when the record may be challenged formally.
For cad & engineering drawings, the cost is based on the number of files you anchor, not the file size. Scheduled timestamps use 1 credit per file, while verified instant timestamps use 2 credits per file.
Privacy
Your cad & engineering drawings never leave your computer. TimeProof uses client-side file hashing (SHA-256). Only the 64-character hash string is sent for anchoring. Because SHA-256 is one-way, it is not possible to reconstruct the original file from the hash. That lets architects, engineers, product designers, manufacturers protect client work, unpublished material, and high-value source files without exposing the underlying content.