The Crovia Seal: A Cryptographic Receipt Format for AI-Generated Output Provenance
draft-crovia-seal-01
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| Last updated | 2026-05-05 | ||
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draft-crovia-seal-01
Independent Submission T. En Nakhai
Internet-Draft Crovia Trust
Intended status: Informational May 2026
Expires: 6 November 2026
The Crovia Seal: A Cryptographic Receipt Format for AI-Generated Output
Provenance
draft-crovia-seal-01
Abstract
This document specifies the Crovia Seal v1, a compact, tamper-evident
JSON receipt that may be attached to any output produced by an AI
generator (large language model, image model, audio model, or
composite system) to record its provenance in a cryptographically
verifiable form. A Crovia Seal binds an issuer's identity to the
SHA-256 digests of an input/output pair, the identity and parameters
of the generator, an emission timestamp, and a per-issuer hash chain,
under an Ed25519 signature computed over a strict canonicalization
(CSC-1) of the receipt with explicit domain separation. Optional
fields permit transparency-log inclusion proofs and witness co-
signatures. The Seal is designed for offline verification and for
inclusion in third-party transparency logs and standards-based
revocation infrastructure.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress".
This Internet-Draft will expire on 5 November 2026.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 2 November 2026.
Copyright Notice
Copyright (c) 2026 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions and Terminology . . . . . . . . . . . . . . . 4
1.2. Design Principles . . . . . . . . . . . . . . . . . . . . 4
1.3. Out of Scope . . . . . . . . . . . . . . . . . . . . . . 5
2. Canonicalization (CSC-1) . . . . . . . . . . . . . . . . . . 5
2.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Rules . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3. Signing Payload . . . . . . . . . . . . . . . . . . . . . 6
3. Seal Structure . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. Top-Level Fields . . . . . . . . . . . . . . . . . . . . 7
3.2. seal_version . . . . . . . . . . . . . . . . . . . . . . 8
3.3. seal_id . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.4. issuer . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.5. subject . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.6. generator . . . . . . . . . . . . . . . . . . . . . . . . 9
3.7. timestamp . . . . . . . . . . . . . . . . . . . . . . . . 9
3.8. chain . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.9. checks (OPTIONAL) . . . . . . . . . . . . . . . . . . . . 10
3.10. anchor (OPTIONAL) . . . . . . . . . . . . . . . . . . . . 10
3.11. signature . . . . . . . . . . . . . . . . . . . . . . . . 11
4. Witnesses (OPTIONAL) . . . . . . . . . . . . . . . . . . . . 11
5. Transparency Log (Informative) . . . . . . . . . . . . . . . 11
6. Algorithm Agility (Post-Quantum) . . . . . . . . . . . . . . 12
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7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
7.1. Replay Across Protocols . . . . . . . . . . . . . . . . . 12
7.2. Replay Within the Protocol . . . . . . . . . . . . . . . 12
7.3. JSON Malleability . . . . . . . . . . . . . . . . . . . . 12
7.4. Field Tampering . . . . . . . . . . . . . . . . . . . . . 12
7.5. Key Compromise . . . . . . . . . . . . . . . . . . . . . 12
7.6. Downgrade . . . . . . . . . . . . . . . . . . . . . . . . 13
7.7. Canonicalization Ambiguity . . . . . . . . . . . . . . . 13
7.8. Hash Choice . . . . . . . . . . . . . . . . . . . . . . . 13
7.9. Randomness . . . . . . . . . . . . . . . . . . . . . . . 13
7.10. Content Privacy . . . . . . . . . . . . . . . . . . . . . 13
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
8.1. Media Type Registration . . . . . . . . . . . . . . . . . 13
8.2. URN Sub-Namespace Registration . . . . . . . . . . . . . 14
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.1. Normative References . . . . . . . . . . . . . . . . . . 14
9.2. Informative References . . . . . . . . . . . . . . . . . 15
Appendix A. Reference Implementation . . . . . . . . . . . . . . 15
Appendix B. Changelog . . . . . . . . . . . . . . . . . . . . . 15
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 16
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
Outputs produced by automated generative systems (large language
models, diffusion image models, speech-synthesis pipelines, or
composite agents) are difficult to attribute reliably after they
leave the generating system. Today, an output may be quoted, edited,
copy-pasted, ingested into a search index, surfaced in a court
filing, or attributed to the wrong vendor with no available chain of
custody. Both vendors and downstream consumers have an operational
interest in an attestation that fixes, at the moment of generation,
the bytes that were produced and the parameters under which they were
produced.
This document specifies a single such attestation: the *Crovia Seal*.
A Seal is a JSON object whose bytes are signed by an issuer's Ed25519
private key after a deterministic canonicalization (Section 3) and
with explicit cryptographic domain separation (Section 3.3). A Seal
carries the SHA-256 digest of the input that was provided to the
generator, the SHA-256 digest of the output, the generator identity
and generation parameters, an issuance timestamp, and a per-issuer
append-only hash chain. Optional fields carry inclusion proofs from
public transparency logs and additional co-signatures ("witnesses").
A Seal does *not* attest to the truthfulness, lawfulness,
originality, or safety of the output. It is a receipt, not a
verdict. This deliberate narrowness is essential to the protocol's
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value: the Seal can be re-verified by any party possessing only the
Seal, the issuer's public key, and the original output bytes, without
dependence on any judgement that cannot be cryptographically checked.
1.1. Conventions and Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The following terms are used throughout this document:
Seal: a single JSON object conforming to Section 3.
Issuer: the entity producing and signing Seals; identified by its
long-term Ed25519 public key.
Witness: an optional co-signer of a Seal (Section 4).
Subject: the input/output pair that the Seal describes.
Generator: the AI model or system that produced the output.
Chain: the per-issuer append-only sequence of Seals (Section 3.8).
Anchor: an optional proof that the Seal was included in a public
transparency log (Section 5).
CSC-1: Crovia Seal Canonicalization v1 (Section 2).
Payload: the exact byte sequence over which a signature is computed
(Section 2.3).
1.2. Design Principles
* *Record, do not judge.* The Seal MUST NOT encode verdicts on
lawfulness, harm, or quality. It MAY embed analytical signals
with explicit confidence.
* *Verify offline.* The core verification path MUST require no
network access.
* *Composable.* The schema MUST permit optional extensions (co-
signatures, post-quantum signatures, transparency anchors) without
breaking base verifiers.
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* *Canonical.* The exact bytes that are signed MUST be derivable
from the Seal by a single, fully specified canonicalization
algorithm.
* *Defensive by default.* All cryptographic operations MUST use
domain separation; no signed payload may be replayed in another
protocol.
* *Fail closed.* Any unrecognized field or algorithm MUST cause
verification to fail unless the verifier explicitly opts into
permissive mode.
1.3. Out of Scope
The following are explicitly out of scope for this specification. An
attestation that silently included any of them would be misunderstood
by users:
* Detection of AI-generated content from the output alone (no
watermarking).
* Judgements about copyright, fairness, accuracy, or safety of the
output.
* Revocation: a Seal, once emitted, is an immutable historical
record. Issuers are identified by public key; key rotation is
handled by the transparency log, not by Seal-level revocation.
* Authentication of the human user that requested the generation.
The Seal binds bytes, not personhoods.
* Confidentiality. Seals are over plaintext.
2. Canonicalization (CSC-1)
2.1. Motivation
JSON [RFC8259] is syntactically flexible: whitespace, key ordering,
number formatting, and string-escape choices can vary while producing
the same logical value. A signature over a JSON text requires an
unambiguous serialization.
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CSC-1 is a strict subset of the JSON Canonicalization Scheme (JCS)
[RFC8785]. It adopts the deterministic ordering and escaping rules
of JCS but forbids floating-point numbers in signed payloads,
sidestepping the edge cases of ECMA-262 number serialization. This
restriction does not constrain use cases: continuous parameters such
as temperature MUST be encoded as strings when carried inside the
signed payload (Section 3.6).
2.2. Rules
A CSC-1-serialized JSON value is a UTF-8 byte sequence produced as
follows:
1. null -> null
2. true / false -> true / false
3. integers (JSON number with no fractional part, within [-(2^53 -
1), 2^53 - 1]) -> shortest decimal representation, no leading
zeros, no + sign.
4. strings -> UTF-8 JSON string literal using only the escapes
required by [RFC8259]: \", \\, \b, \f, \n, \r, \t, and \u00XX for
U+0000..U+001F. All other code points MUST be emitted literally.
5. arrays -> [ followed by canonicalized elements separated by ,
followed by ]. No interior whitespace.
6. objects -> { followed by "key":value pairs separated by ,
followed by }. Keys MUST be sorted ascending by their UTF-16
code-unit sequence (equivalent to JavaScript Array.prototype.sort
on strings). No interior whitespace.
7. floats, NaN, Infinity, and -0 MUST cause serialization to fail
with NonCanonicalNumber.
8. duplicate object keys MUST cause serialization to fail with
DuplicateKey.
9. non-string object keys MUST cause serialization to fail with
NonStringKey.
2.3. Signing Payload
Given a Seal _S_, the signing payload _P(S)_ is computed as:
P(S) = DOMAIN || 0x0A || CSC1(S \ {signature, witnesses})
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where:
* DOMAIN is the ASCII string "CROVIA-SEAL-v1" (14 bytes).
* 0x0A is a single newline byte, acting as an unambiguous separator.
* S \ {signature, witnesses} denotes the Seal with the signature and
witnesses top-level fields removed (they are computed over the
payload, not part of it).
* CSC1(...) is the UTF-8 serialization per Section 2.2.
The DOMAIN prefix ensures that a signature over _P(S)_ cannot be
replayed as a valid signature in any other protocol that does not use
the same prefix. Implementations MUST NOT omit the prefix.
Verifiers MUST reject any Seal whose signature was produced without
the prefix.
3. Seal Structure
3.1. Top-Level Fields
A conformant Seal is a JSON object with exactly the top-level fields
listed below. Unknown top-level fields MUST cause verification to
fail (the "fail closed" principle).
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+==============+==========+========+=========+
| Field | Required | Type | Section |
+==============+==========+========+=========+
| seal_version | MUST | string | 4.2 |
+--------------+----------+--------+---------+
| seal_id | MUST | string | 4.3 |
+--------------+----------+--------+---------+
| issuer | MUST | object | 4.4 |
+--------------+----------+--------+---------+
| subject | MUST | object | 4.5 |
+--------------+----------+--------+---------+
| generator | MUST | object | 4.6 |
+--------------+----------+--------+---------+
| timestamp | MUST | object | 4.7 |
+--------------+----------+--------+---------+
| chain | MUST | object | 4.8 |
+--------------+----------+--------+---------+
| checks | OPTIONAL | object | 4.9 |
+--------------+----------+--------+---------+
| anchor | OPTIONAL | object | 4.10 |
+--------------+----------+--------+---------+
| signature | MUST | object | 4.11 |
+--------------+----------+--------+---------+
| witnesses | OPTIONAL | array | 6 |
+--------------+----------+--------+---------+
Table 1
3.2. seal_version
The literal string "crovia.seal.v1". Any other value MUST cause
verification to fail.
3.3. seal_id
A string matching the regular expression ^cs_[0-9]{4}_[A-Z2-7]{26}$:
prefix cs_, 4-digit issuance year, underscore, 26 RFC 4648 base32
characters [RFC4648] (alphabet A-Z, 2-7, no padding) encoding 16
random bytes (128 bits). The random bytes MUST be produced by a
cryptographically secure source.
3.4. issuer
{
"id": string, ; urn:crovia:seal-issuer:<name>
"pubkey": { "alg": "ed25519", "key_hex": string }
}
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key_hex is 64 lowercase hexadecimal characters (32 raw bytes, Ed25519
public key per [RFC8032]). Other algorithms are reserved for
Section 6.
3.5. subject
{
"input_hash": "sha256:" + 64 lowercase hex chars,
"output_hash": "sha256:" + 64 lowercase hex chars,
"input_len": integer, ; byte length of input
"output_len": integer, ; byte length of output
"modality": string ; one of: text/code/image/audio/multimodal
}
The Seal does NOT carry the content itself. The hashes commit to the
content; verifiers who possess the content can re-hash and compare.
3.6. generator
{
"id": string, ; e.g. "openai/gpt-4o"
"version": string | null, ; e.g. "2024-08-06"
"weights_hash": string | null, ; if available
"params": object ; key -> string map of gen-params
}
All parameter values MUST be strings in the signed payload (per the
floating-point restriction in Section 2). Numeric values like
temperature=0.7 MUST be encoded as "0.7".
3.7. timestamp
{
"emitted_at": string, ; RFC 3339 UTC, ms precision
; e.g. "2026-04-15T12:34:56.789Z"
"nonce": string ; 26 RFC 4648 base32 chars (16 random bytes)
}
emitted_at follows [RFC3339]. Issuers MUST use UTC. The nonce
guarantees that two Seals issued in the same millisecond are still
distinct under P(S).
3.8. chain
{
"prev_seal_hash": "sha256:" + 64 hex chars | null,
"sequence": integer (>= 0)
}
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prev_seal_hash is the SHA-256 over the canonical payload _P(S_prev)_
of the immediately preceding Seal from the same issuer, or null for
the genesis Seal (sequence == 0). Verifiers that track issuer chains
MUST detect:
* *Fork*: two Seals with the same issuer key and same chain.sequence
but different prev_seal_hash. This is non-repudiable evidence of
issuer misbehavior or key compromise.
* *Gap*: missing sequence numbers. A verifier with partial history
SHOULD obtain the missing Seals from the transparency log before
accepting.
3.9. checks (OPTIONAL)
Free-form object carrying analytical claims such as memorization
checks, safety probes, toxicity scores. The schema for specific
check types is defined in separate check specifications; the Seal
itself imposes no constraints on the content beyond CSC-1
compatibility.
Example:
{
"memorization": {
"db_version": "crovia-memdb-2026-04-15",
"method": "ngram-lsh-v1",
"matches": 0,
"max_conf": "0.03"
}
}
Each check produced by an issuer is signed along with the rest of the
Seal; its validity as evidence depends on the method's own
robustness, which is out of scope for this specification.
3.10. anchor (OPTIONAL)
{
"log_url": string,
"merkle_root": "sha256:" + 64 hex chars,
"merkle_proof": [ "sha256:" + hex, ... ],
"log_index": integer (>= 0),
"root_signed_at": string (RFC 3339 UTC)
}
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The anchor commits the Seal to a public transparency log. The log
operator's signature over merkle_root is not part of this Seal and
MUST be fetched separately from log_url.
3.11. signature
{
"alg": "ed25519",
"canon": "csc-1",
"domain": "CROVIA-SEAL-v1",
"payload_hash_alg": "sha256",
"sig_hex": string ; 128 hex chars (64 raw bytes)
}
The signature is computed as Ed25519_sign(privkey, P(S)) where _P(S)_
is defined in Section 2.3. Implementations MUST NOT hash the payload
before signing; Ed25519 internally handles the hash (SHA-512). The
payload_hash_alg field is informational, indicating the algorithm
used to derive prev_seal_hash and other SHA-256 digests in the Seal.
4. Witnesses (OPTIONAL)
"witnesses": [
{
"id": string,
"pubkey": { "alg": "ed25519", "key_hex": string },
"sig_hex": string
},
...
]
A witness signs the same canonical payload _P(S)_ as the issuer.
Witness signatures are OPTIONAL and additive: a Seal with no
witnesses is valid; a Seal with invalid witness signatures is invalid
overall (fail-closed).
Typical witnesses: consortium co-signers (civil-society
organizations, academic institutions, regulatory observers).
Witnesses endorse the Seal without endorsing its content.
5. Transparency Log (Informative)
A conformant transparency log accepts Seals and periodically
publishes a signed Merkle root over the Seals it has received. The
log API design is outside the scope of this document; an
implementation profile compatible with [RFC9162]-style logs is
anticipated in a companion document.
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6. Algorithm Agility (Post-Quantum)
Future versions of this specification MAY permit alternative
signature algorithms (e.g., Dilithium, Falcon) by extending the
signature.alg vocabulary. A Seal MAY additionally carry a
pq_signature top-level field with an independent post-quantum
signature over the same payload _P(S)_. Verifiers that support only
Ed25519 MUST ignore pq_signature and rely on signature. Verifiers
MAY require both signatures to validate (strict mode).
7. Security Considerations
7.1. Replay Across Protocols
Prevented by domain separation (Section 2.3). A signature on _P(S)_
cannot be reinterpreted as a valid signature on a payload of any
other protocol that does not use the exact same 14-byte CROVIA-
SEAL-v1 prefix followed by a newline.
7.2. Replay Within the Protocol
A Seal is a historical record; "replay" of a Seal is a semantic
issue, not a cryptographic one. The seal_id, timestamp, and
chain.sequence fields make each Seal unique. Verifiers that track
seen seal IDs can detect duplication attempts.
7.3. JSON Malleability
Eliminated by CSC-1 (Section 2). Any tool that reorders keys, adds
whitespace, or re-escapes strings produces a different byte sequence
and hence an invalid signature.
7.4. Field Tampering
The signature covers every field except signature and witnesses,
which are themselves cryptographic. Adding, modifying, or deleting
any field invalidates the signature.
7.5. Key Compromise
If an issuer key is compromised, the attacker can issue valid Seals
until the compromise is detected and the key is revoked in the
transparency log's trust root. The issuer hash chain MAY reveal the
compromise if the attacker issues a forking Seal.
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7.6. Downgrade
seal_version, signature.alg, signature.canon, and signature.domain
are all inside the signed payload. An attacker cannot negotiate a
weaker algorithm without producing a wholly new signature.
7.7. Canonicalization Ambiguity
CSC-1 forbids floats in the signed payload precisely to avoid the
numeric edge cases of JCS. Strings carrying numeric values MUST use
a documented format (see Section 3.6).
7.8. Hash Choice
SHA-256 is used for all digests (content commitments, chain links).
Migration to SHA-3 or BLAKE3 is anticipated in a future minor
version; the payload_hash_alg field signals the choice.
7.9. Randomness
All random values (seal_id suffix, timestamp.nonce) MUST be produced
by a cryptographically secure source (e.g., os.urandom, the secrets
module in Python, crypto.randomBytes in Node.js).
7.10. Content Privacy
The Seal commits to input/output hashes, never content. Content-
bearing fields such as generator.params are in the clear; issuers
MUST NOT place sensitive user data in these fields.
8. IANA Considerations
8.1. Media Type Registration
IANA is requested to register the following media type per [RFC6838]:
Type name: application
Subtype name: vnd.crovia.seal+json
Required parameters: none
Optional parameters: none
Encoding: UTF-8 (per [RFC8259])
Security considerations: see Section 7
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Interoperability: see this document
Published specification: this document
Applications using this type: provenance attestation systems for AI-
generated content
Author/Change controller: CROVIA Research
8.2. URN Sub-Namespace Registration
IANA is requested to register the URN namespace urn:crovia:seal-
issuer: per [RFC8141] for the identification of Crovia Seal issuers
by stable URN. The complete formal namespace registration template
will be provided in a companion document.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
Timestamps", RFC 3339, July 2002,
<https://www.rfc-editor.org/info/rfc3339>.
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, October 2006,
<https://www.rfc-editor.org/info/rfc4648>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13,
RFC 6838, January 2013,
<https://www.rfc-editor.org/info/rfc6838>.
[RFC8032] Josefsson, S. and I. Liusvaara, "Edwards-Curve Digital
Signature Algorithm (EdDSA)", RFC 8032, January 2017,
<https://www.rfc-editor.org/info/rfc8032>.
[RFC8141] Saint-Andre, P. and J. Klensin, "Uniform Resource Names
(URNs)", RFC 8141, April 2017,
<https://www.rfc-editor.org/info/rfc8141>.
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[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, May 2017,
<https://www.rfc-editor.org/info/rfc8174>.
[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259, December 2017,
<https://www.rfc-editor.org/info/rfc8259>.
[RFC8785] Rundgren, A., Jordan, B., and S. Erdtman, "JSON
Canonicalization Scheme (JCS)", RFC 8785, June 2020,
<https://www.rfc-editor.org/info/rfc8785>.
9.2. Informative References
[C2PA] Coalition for Content Provenance and Authenticity, "C2PA
Content Credentials Specification, Version 1.3", 2024,
<https://c2pa.org/specifications/specifications/1.3/specs/
C2PA_Specification.html>.
[RFC9162] Laurie, B., Messeri, E., and R. Stradling, "Certificate
Transparency Version 2.0", RFC 9162, December 2021,
<https://www.rfc-editor.org/info/rfc9162>.
[SIGSTORE] The Linux Foundation, "Sigstore: Software signing for
everyone", 2021, <https://www.sigstore.dev/>.
Appendix A. Reference Implementation
A reference implementation in Python and TypeScript, including a
public sealing service, an in-browser verifier, and a set of
normative test vectors, is available at
https://croviatrust.com/registry/seal/. Test vectors are linked from
https://croviatrust.com/registry/seal/spec/.
Appendix B. Changelog
*draft-crovia-seal-01* (May 2026):
* Editorial: replaced 6 Unicode arrow characters (U+2192) with ASCII
-> so the rendered text file is strictly ASCII-clean (0 idnits
warnings). No normative changes.
*draft-crovia-seal-00* (May 2026):
* Initial submission. Aligned with Crovia Seal Specification v0.5
of April 2026.
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Acknowledgements
The Crovia Seal has been informed by extensive prior work in
cryptographic transparency ([RFC9162], [SIGSTORE]) and media-
provenance attestation ([C2PA]). The authors thank the broader
community working on AI provenance and tamper-evidence for the
intellectual foundations on which this work rests.
Author's Address
Tarik En Nakhai
Crovia Trust
Italy
Email: info@croviatrust.com
URI: https://croviatrust.com
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