⬡ AGPLv3 · Open Protocol · USPTO #99657348

Clawback Protocol

You shared it. You can unshare it.

Cryptographically enforced, revocable, time-limited data sharing with provable destruction. Not a policy. A mathematical guarantee.

View on GitHub → Read the Whitepaper

Core Properties

Data revocation as a first-class primitive

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Zero-Knowledge Broker
The broker stores encrypted payloads and never sees plaintext. Your data stays yours.
Instant Revocation
Revoke access in real time. The share key is destroyed on the broker — access becomes mathematically impossible.
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Provable Destruction
Tamper-evident destruction receipts prove deletion cryptographically. Not "trust us" — math.
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Per-Share Keys
Each recipient gets a unique derived key. Revoke one share without affecting others.
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Time-Limited Access
Set expiry on any share. Access auto-revokes when the window closes — no action required.
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Open Standard
AGPLv3. Designed for IETF standardization. Built to become an internet primitive, not a product.

Protocol Flow

How it works

Sender encrypts data locally → registers with Broker
Broker holds ciphertext + per-share key (never sees plaintext)
Receiver presents share token → gets encrypted blob + share key
Receiver decrypts locally → reads plaintext
Sender revokes → Broker destroys share key instantly
Receiver tries again → 403 REVOKED
Destruction receipt logged → cryptographic proof of deletion

Cryptographic Stack

Built on proven primitives

Key Exchange X25519
Encryption ChaCha20-Poly1305
Key Derivation HKDF-SHA256
Destruction Proof HMAC-SHA256
Reference Impl Rust + axum
Future Umbral PRE + ZK

Build on Clawback Protocol

Open source, AGPLv3. Reference implementation in Rust. Whitepaper available. Contributions welcome.

View on GitHub → Get in Touch