diff --git a/Tests/XSTSSuiteTests.swift b/Tests/XSTSSuiteTests.swift
index 643a481..650c7fb 100644
--- a/Tests/XSTSSuiteTests.swift
+++ b/Tests/XSTSSuiteTests.swift
@@ -78,11 +78,31 @@ struct XSTSSuiteTests {
     /// not the parser's Fifth Edition production, so a Fifth-Edition-only name char
     /// (the combining mark U+0346) no longer matches `\c` (reZ006i now rejects). See
     /// ``XSDNameCharacter``.
-    private let knownInstanceInvalidAccepted = 11
-    /// Instance tests excluded from the counts. Empty: the Ethiopic-digit `\d` cases
-    /// (reS17.v, reS38.v, reZ004v.v) were not divergent but a 3.2-repertoire bug, now
-    /// fixed, so they are counted as ordinary agreements rather than excluded.
-    private static let specDivergentInstances: Set<String> = []
+    /// 11 -> 10: anyURI_a004_1339.i reclassified as a contested test, not a bug (see
+    /// the excluded set below). PureXML's acceptance is spec-correct; the suite's
+    /// expectation is internally inconsistent.
+    private let knownInstanceInvalidAccepted = 10
+    /// Instance tests excluded from the counts because their expected validity is not
+    /// authoritative, mirroring how the suite's own `status="queried"` entries are
+    /// skipped. Each must carry a spec-grounded justification; this is never a place to
+    /// hide a real deviation.
+    ///
+    /// - `anyURI_a004_1339.i`: the suite pairs a `valid` schemaTest with an `invalid`
+    ///   instanceTest, but the two are mutually inconsistent. The schema's `include`,
+    ///   `import`, and `redefine` have unresolvable schemaLocations; XSD 1.0 §4.2.1
+    ///   makes an unresolvable `include` "not an error" (no inclusion performed), the
+    ///   `import` likewise, and the empty `redefine` imposes no resolution requirement
+    ///   (`src-redefine` clause 1 gates that on non-annotation children), so the schema
+    ///   is conformantly valid (agreeing with the schemaTest). The only components the
+    ///   instance exercises (`root`, `bar`, `st`, `att`) are fully locally defined, and
+    ///   every instance value is byte-identical to one of the type's six anyURI
+    ///   `enumeration` members, so a strict assessment of the document element is
+    ///   valid. There is no spec path to valid-schema + invalid-instance. Confirmed by
+    ///   two independent adversarial analyses; libxml2 is no authority here (it
+    ///   non-conformantly fails to compile the schema on the unresolvable include).
+    ///   Matching the suite would mean rejecting a valid instance whenever an include
+    ///   cannot be resolved, a false positive an IDE editing loop hits constantly.
+    private static let specDivergentInstances: Set<String> = ["anyURI_a004_1339.i"]
 
     @Test("Every XSTS case behaves: compile, reject, validate, invalidate")
     func test_suite() throws {
diff --git a/docs/xsts-deviations.md b/docs/xsts-deviations.md
index 49b54df..905c4b1 100644
--- a/docs/xsts-deviations.md
+++ b/docs/xsts-deviations.md
@@ -86,11 +86,27 @@ rule is marked ambiguous by the suite itself (RecurseAsIfGroup); `mgO013` is an
 non-absolute namespace URIs. The multi-document `sch*` / `targetns` cases need
 per-schema pairing before a verdict.
 
+`anyURI_a004_1339.i` is reclassified as a contested test, not a deviation
+(`invalid-instances-accepted` 11 -> 10, now excluded like the suite's `queried`
+entries). The suite pairs a `valid` schemaTest with an `invalid` instanceTest, but
+the two are mutually inconsistent: the schema's `include`/`import`/`redefine` have
+unresolvable schemaLocations, which XSD 1.0 §4.2.1 makes "not an error" (no
+inclusion performed; the empty `redefine` imposes no resolution requirement per
+`src-redefine` clause 1), so the schema is conformantly valid, and the only
+components the instance exercises (`root`/`bar`/`st`/`att`) are fully locally
+defined with every value byte-identical to one of the type's six anyURI
+`enumeration` members, so the instance is valid. There is no spec path to
+valid-schema + invalid-instance. Two independent adversarial analyses failed to
+refute this; libxml2 is no authority (it non-conformantly fails to compile the
+schema on the unresolvable include). Matching the suite would reject a valid
+instance whenever an include cannot be resolved, a false positive an IDE hits
+constantly. Recorded in `XSTSSuiteTests.specDivergentInstances`.
+
 Takeaway: on the schema side, libxml2 parity is reached except the one case now
 fixed; the remaining nine are a deliberate choice to exceed the reference. On the
 instance side the Ethiopic-digit `\d`/`\D` and `\i`/`\c` name-class cases are now
-fixed (reference-aligned); the remaining reference-aligned cases are real but each
-needs its own analysis, not a sweep.
+fixed (reference-aligned) and `anyURI_a004_1339` is shown contested; the remaining
+reference-aligned cases are real but each needs its own analysis, not a sweep.
 
 ## Category A: genuine correctness bugs