diff --git a/MAINTAINERS.md b/MAINTAINERS.md
index 1451b9b..6cff6ab 100644
--- a/MAINTAINERS.md
+++ b/MAINTAINERS.md
@@ -4,7 +4,7 @@
 
 | Name | Affiliation | GitHub | Contact |
 |---|---|---|---|
-| Imran Siddique | OPAQUE Systems | @imraan | imran.siddique@opaque.co |
+| Imran Siddique | OPAQUE Systems | @imraan | maintainers@agentrust.io |
 
 The Project Lead has final decision authority on specification changes, AAIF/CoSAI submission scope, conformance requirements, and Maintainer appointments.
 
diff --git a/README.md b/README.md
index 1c6a7a2..0a1bf32 100644
--- a/README.md
+++ b/README.md
@@ -83,7 +83,6 @@ The record is a single EAT envelope (RFC 9711). Each field is independently veri
 | `amd-sev-snp` | Yes | Yes | |
 | `nvidia-h100` | Yes | Yes | |
 | `gpu-cc` | No | Planned | Generic GPU confidential compute |
-| `opaque` | Yes | Yes | Explicit opt-in; contact maintainers |
 
 ## Specification
 
diff --git a/src/agentrust_trace/models.py b/src/agentrust_trace/models.py
index 847a5fb..e565e37 100644
--- a/src/agentrust_trace/models.py
+++ b/src/agentrust_trace/models.py
@@ -113,7 +113,7 @@ class TrustRecord(BaseModel):
 
     eat_profile: Literal["tag:agentrust.io,2026:trace-v0.1"]
     iat: Annotated[int, Field(ge=1700000000)]
-    subject: Annotated[str, Field(pattern=r"^(spiffe://|did:)")]
+    subject: Annotated[str, Field(pattern=r"^(spiffe://[^/]+/.+|did:[a-z0-9]+:.+)$")]
     model: ModelInfo
     runtime: RuntimeInfo
     policy: PolicyInfo
diff --git a/src/agentrust_trace/schema/trace-v0.1.json b/src/agentrust_trace/schema/trace-v0.1.json
index 0c03bb2..c009bd5 100644
--- a/src/agentrust_trace/schema/trace-v0.1.json
+++ b/src/agentrust_trace/schema/trace-v0.1.json
@@ -167,7 +167,7 @@
       "properties": {
         "slsa_level": {
           "type": "integer",
-          "minimum": 1,
+          "minimum": 0,
           "maximum": 3,
           "description": "SLSA Build Level achieved. Level 2 minimum for TRACE conformance; Level 3 for production mark."
         },
diff --git a/src/agentrust_trace/validate.py b/src/agentrust_trace/validate.py
index 8a43ab3..e5bc5cd 100644
--- a/src/agentrust_trace/validate.py
+++ b/src/agentrust_trace/validate.py
@@ -16,7 +16,7 @@ def _schema() -> dict[str, Any]:
 
 @lru_cache(maxsize=1)
 def _validator() -> jsonschema.Draft202012Validator:
-    return jsonschema.Draft202012Validator(_schema())
+    return jsonschema.Draft202012Validator(_schema(), format_checker=jsonschema.FormatChecker())
 
 
 # Canonical schema exposed for downstream tooling that needs the raw dict.
diff --git a/tests/test_sign.py b/tests/test_sign.py
index a95ca43..102051c 100644
--- a/tests/test_sign.py
+++ b/tests/test_sign.py
@@ -1,7 +1,6 @@
 """Tests for agentrust_trace.sign."""
 
 import base64
-import json
 
 import pytest
 from cryptography.exceptions import InvalidSignature