diff --git a/src/openultrasast/learn/schema.py b/src/openultrasast/learn/schema.py
index 3a48e5d..d34e10e 100644
--- a/src/openultrasast/learn/schema.py
+++ b/src/openultrasast/learn/schema.py
@@ -102,7 +102,12 @@ EXCLUDED_FIELDS = frozenset(
 # Entries name an instrument (all its state and values) or a single feature. v1 withholds the engine and the function
 # length: both separate fixed from vulnerable pair sides by construction (a fix removes a sink, a guard lengthens the
 # function), not by anything that holds on unseen code (leak audit 2026-10-01).
-INPUT_PROFILES: Mapping[str, tuple[str, ...]] = {"v1": ("engine", "facts.function_lines"), "full": ()}
+# The plane profile also withholds verify.flag_b and ms.operation in v1 (maintainer decision 2026-10-02 on the
+# slice-2 leak audit: they separate pair sides because a fix removes the sink, which does not hold on unseen code).
+INPUT_PROFILES: Mapping[str, tuple[str, ...]] = {
+    "v1": ("engine", "facts.function_lines", "verify.flag_b", "ms.operation"),
+    "full": (),
+}
 DEFAULT_INPUTS = "v1"
 
 
diff --git a/tests/test_learn_leaks.py b/tests/test_learn_leaks.py
index a9b44a7..70a66f1 100644
--- a/tests/test_learn_leaks.py
+++ b/tests/test_learn_leaks.py
@@ -113,3 +113,13 @@ def test_v1_withholds_function_length_from_prompts_and_distance() -> None:
     assert "facts.function_lines: 42" in render_signals(a["x"], a["instruments"], "static", inputs="full")
     assert gower(a["x"], a["instruments"], b["x"], b["instruments"], "static") == 0.0
     assert gower(a["x"], a["instruments"], b["x"], b["instruments"], "static", inputs="full") > 0.0
+
+
+def test_v1_withholds_the_plane_profile_leak_signals() -> None:
+    """Slice-2 leak audit (2026-10-02): verify.flag_b and ms.operation track the pair label in the plane profile;
+    v1 renders neither and the distance ignores both, while ``full`` keeps them."""
+    from openultrasast.learn.schema import withheld
+
+    hidden = withheld("v1")
+    assert {"verify.flag_b", "ms.operation", "engine", "facts.function_lines"} <= hidden
+    assert withheld("full") == frozenset()