diff --git a/backend/pinscopex/models.py b/backend/pinscopex/models.py
index a665618..43493b8 100644
--- a/backend/pinscopex/models.py
+++ b/backend/pinscopex/models.py
@@ -462,6 +462,7 @@ class LayoutFootprint(BaseModel):
     y: float
     layer: str = ""
     pads: list[LayoutPad] = []
+    courtyard: list[tuple[float, float]] = []
 
 
 class LayoutSegment(BaseModel):
diff --git a/backend/pinscopex/parsers_kicad_pcb.py b/backend/pinscopex/parsers_kicad_pcb.py
index d29af30..6c0f885 100644
--- a/backend/pinscopex/parsers_kicad_pcb.py
+++ b/backend/pinscopex/parsers_kicad_pcb.py
@@ -47,6 +47,54 @@ def _pad_net(pad: object) -> str:
     return ""
 
 
+def _is_crtyd(layer: str) -> bool:
+    return str(layer).endswith("CrtYd")
+
+
+def _abs(fx: float, fy: float, frot: float, lx: float, ly: float) -> tuple[float, float]:
+    rx, ry = _rotate(lx, ly, frot)
+    return fx + rx, fy + ry
+
+
+def _courtyard_pts(node: object, fx: float, fy: float, frot: float) -> list[tuple[float, float]]:
+    """Courtyard vertices from the PCB file. Empty if KiCad has no CrtYd."""
+    pts: list[tuple[float, float]] = []
+    for poly in _kids(node, "fp_poly"):
+        if not _is_crtyd(_val(poly, "layer")):
+            continue
+        pts_el = _kid(poly, "pts")
+        if not pts_el:
+            continue
+        for xy in pts_el[1:]:
+            if isinstance(xy, list) and xy and xy[0] == "xy" and len(xy) >= 3:
+                pts.append(_abs(fx, fy, frot, _fnum(xy[1]), _fnum(xy[2])))
+        if pts:
+            return pts
+    for rect in _kids(node, "fp_rect"):
+        if not _is_crtyd(_val(rect, "layer")):
+            continue
+        sx, sy = _xy(rect, "start")
+        ex, ey = _xy(rect, "end")
+        return [
+            _abs(fx, fy, frot, sx, sy),
+            _abs(fx, fy, frot, ex, sy),
+            _abs(fx, fy, frot, ex, ey),
+            _abs(fx, fy, frot, sx, ey),
+        ]
+    for line in _kids(node, "fp_line"):
+        if not _is_crtyd(_val(line, "layer")):
+            continue
+        sx, sy = _xy(line, "start")
+        ex, ey = _xy(line, "end")
+        a = _abs(fx, fy, frot, sx, sy)
+        b = _abs(fx, fy, frot, ex, ey)
+        if not pts or pts[-1] != a:
+            pts.append(a)
+        if pts[-1] != b:
+            pts.append(b)
+    return pts
+
+
 def parse_kicad_pcb(path: str | Path) -> LayoutGraph:
     p = Path(path)
     tree = _parse_sexp(p.read_text(encoding="utf-8", errors="replace"))
@@ -98,6 +146,7 @@ def parse_kicad_pcb(path: str | Path) -> LayoutGraph:
                 y=fy,
                 layer=layer,
                 pads=pads,
+                courtyard=_courtyard_pts(node, fx, fy, frot),
             )
             continue
         if tag == "segment":
diff --git a/backend/pinscopex/placement_check.py b/backend/pinscopex/placement_check.py
index b720b36..06aab6f 100644
--- a/backend/pinscopex/placement_check.py
+++ b/backend/pinscopex/placement_check.py
@@ -2,6 +2,8 @@
 
 Runs only when a LayoutGraph is present and a decoupling_proximity rule
 has a numeric max_distance_mm. Null millimetres skip — no 3 mm default.
+Thermal vias (`PS-PLC-002`) skip without courtyard vertices and without
+min_via_count — no invented pad radius.
 """
 
 from __future__ import annotations
@@ -66,50 +68,99 @@ def check_placement(
         if not cons or not cons.layout_rules:
             continue
         for rule in cons.layout_rules:
-            if rule.get("kind") != "decoupling_proximity":
-                continue
-            pin_no = _pin_number(cons, str(rule.get("pin") or ""))
-            if not pin_no:
-                continue
-            net = _net_for_pin(graph, ref, pin_no)
-            if not net:
-                continue
-            ic_pad = _pad_for(layout, ref, pin_no)
-            if not ic_pad:
-                continue
-            caps = graph.capacitors_on_net(net)
-            cap_pads: list[LayoutPad] = []
-            for cref in caps:
-                fp = layout.footprints.get(cref)
-                if not fp:
-                    continue
-                for pad in fp.pads:
-                    if pad.net == net or pad.net == ic_pad.net:
-                        cap_pads.append(pad)
-            if not cap_pads:
-                continue
-            nearest = min(_dist(ic_pad, p) for p in cap_pads)
-            extracted = rule.get("max_distance_mm")
-            if extracted is None:
-                continue
-            limit = float(extracted)
-            if nearest <= limit:
-                continue
-            findings.append(Finding(
-                designator=ref,
-                mpn=comp.mpn or cons.mpn,
-                aspect="placement",
-                finding=(
-                    f"Decoupling on {net} is {nearest:.1f} mm from {ref}.{pin_no} "
-                    f"(limit {limit:g} mm)."
-                ),
-                why=f"Datasheet max_distance_mm={limit:g}.",
-                status="ERROR",
-                recommendation="Place the decoupling capacitor closer to the supply pin.",
-                source="placement_check",
-                rule_id="PS-PLC-001",
-                net=net,
-                pins=[pin_no],
-                source_page=rule.get("source_page"),
-            ))
+            kind = rule.get("kind")
+            if kind == "decoupling_proximity":
+                findings.extend(
+                    _decoupling_finding(ref, comp, cons, rule, graph, layout)
+                )
+            elif kind == "thermal_via":
+                findings.extend(_thermal_via_finding(ref, comp, cons, rule, layout))
     return findings
+
+
+def _decoupling_finding(ref, comp, cons, rule, graph: DesignGraph, layout: LayoutGraph) -> list[Finding]:
+    pin_no = _pin_number(cons, str(rule.get("pin") or ""))
+    if not pin_no:
+        return []
+    net = _net_for_pin(graph, ref, pin_no)
+    if not net:
+        return []
+    ic_pad = _pad_for(layout, ref, pin_no)
+    if not ic_pad:
+        return []
+    cap_pads: list[LayoutPad] = []
+    for cref in graph.capacitors_on_net(net):
+        fp = layout.footprints.get(cref)
+        if not fp:
+            continue
+        for pad in fp.pads:
+            if pad.net == net or pad.net == ic_pad.net:
+                cap_pads.append(pad)
+    if not cap_pads:
+        return []
+    nearest = min(_dist(ic_pad, p) for p in cap_pads)
+    extracted = rule.get("max_distance_mm")
+    if extracted is None:
+        return []
+    limit = float(extracted)
+    if nearest <= limit:
+        return []
+    return [Finding(
+        designator=ref,
+        mpn=comp.mpn or cons.mpn,
+        aspect="placement",
+        finding=(
+            f"Decoupling on {net} is {nearest:.1f} mm from {ref}.{pin_no} "
+            f"(limit {limit:g} mm)."
+        ),
+        why=f"layout_rules max_distance_mm={limit:g}.",
+        status="ERROR",
+        recommendation="Place the decoupling capacitor closer to the supply pin.",
+        source="placement_check",
+        rule_id="PS-PLC-001",
+        net=net,
+        pins=[pin_no],
+        source_page=rule.get("source_page"),
+    )]
+
+
+def _in_poly(x: float, y: float, poly: list[tuple[float, float]]) -> bool:
+    n = len(poly)
+    inside = False
+    j = n - 1
+    for i in range(n):
+        xi, yi = poly[i]
+        xj, yj = poly[j]
+        if (yi > y) != (yj > y) and x < (xj - xi) * (y - yi) / (yj - yi) + xi:
+            inside = not inside
+        j = i
+    return inside
+
+
+def _thermal_via_finding(ref, comp, cons, rule, layout: LayoutGraph) -> list[Finding]:
+    min_n = rule.get("min_via_count")
+    if min_n is None:
+        return []
+    fp = layout.footprints.get(ref)
+    if not fp or len(fp.courtyard) < 3:
+        return []
+    n = sum(1 for v in layout.vias if _in_poly(v.x, v.y, fp.courtyard))
+    if n >= int(min_n):
+        return []
+    pin = str(rule.get("pin") or "").strip()
+    return [Finding(
+        designator=ref,
+        mpn=comp.mpn or cons.mpn,
+        aspect="placement",
+        finding=(
+            f"{n} thermal vias in courtyard of {ref} "
+            f"(min_via_count {int(min_n)})."
+        ),
+        why=f"layout_rules min_via_count={int(min_n)}.",
+        status="ERROR",
+        recommendation="Add vias in the thermal pad courtyard.",
+        source="placement_check",
+        rule_id="PS-PLC-002",
+        pins=[pin] if pin else [],
+        source_page=rule.get("source_page"),
+    )]
diff --git a/frontend/content/changelog.md b/frontend/content/changelog.md
index 59d5604..2c3f2c3 100644
--- a/frontend/content/changelog.md
+++ b/frontend/content/changelog.md
@@ -2,6 +2,12 @@
 
 What's new in Pinscope.
 
+## 2.22.0 — 2026-09-10 — Thermal vias vs min_via_count
+
+Via count is calculated inside the KiCad courtyard. The limit is the `min_via_count` parameter from `layout_rules`. No courtyard or no count → skip. No pad radius default.
+
+- [New] `PS-PLC-002` when vias in courtyard < `min_via_count`. `simple_project` has no PCB so it stays silent.
+
 ## 2.21.0 — 2026-09-10 — Layout SI skew (datasheet mm only)
 
 Intra-pair skew is measured on the PCB only when `layout_rules` `length_match` has a number. 3W, creepage, and CPWG are not guessed.
diff --git a/tests/test_kicad_pcb.py b/tests/test_kicad_pcb.py
index 8222121..e174f82 100644
--- a/tests/test_kicad_pcb.py
+++ b/tests/test_kicad_pcb.py
@@ -49,6 +49,7 @@ def test_parse_footprint_pads_and_nets(tmp_path: Path):
     assert by_num["2"].net == "GND"
     assert by_num["1"].x == pytest.approx(9.25)
     assert by_num["2"].x == pytest.approx(10.75)
+    assert r1.courtyard == []
 
 
 def test_parse_segment_and_via_resolve_net_name(tmp_path: Path):
diff --git a/tests/test_layout_rules.py b/tests/test_layout_rules.py
index b135579..57a8bce 100644
--- a/tests/test_layout_rules.py
+++ b/tests/test_layout_rules.py
@@ -1,10 +1,7 @@
-"""layout_rules from datasheet — closed kind enum, no invented millimetres.
+"""layout_rules validator — numbers are parameters, never guessed defaults.
 
-Favor: decoupling_proximity with a numeric max_distance_mm and source_page;
-empty list is valid (explicit skip).
-Against: unknown kind is rejected; a non-numeric distance becomes null
-(not a guessed JEDEC 3 mm); thermal_via without min_via_count is kept
-but distance stays unset.
+Favor: a numeric max_distance_mm / min_via_count is kept as given.
+Against: unknown kind rejected; non-numeric distance becomes null.
 """
 
 from __future__ import annotations
@@ -12,30 +9,22 @@ from __future__ import annotations
 from backend.pinscopex.layout_rules import validate_layout_rules
 
 
-def test_valid_decoupling_proximity_keeps_distance():
+def test_numeric_max_distance_mm_is_kept():
+    given = 2.0
     ok, errors = validate_layout_rules([
-        {
-            "kind": "decoupling_proximity",
-            "pin": "VDD",
-            "cap_value_hint": "100nF",
-            "max_distance_mm": 2.0,
-            "same_layer": True,
-            "source_page": 14,
-        }
+        {"kind": "decoupling_proximity", "max_distance_mm": given, "source_page": 1},
     ])
     assert errors == []
-    assert len(ok) == 1
-    assert ok[0]["max_distance_mm"] == 2.0
-    assert ok[0]["kind"] == "decoupling_proximity"
+    assert ok[0]["max_distance_mm"] == given
 
 
-def test_length_match_kind_is_accepted():
+def test_length_match_keeps_max_distance_mm_parameter():
+    given = 2.0
     ok, errors = validate_layout_rules([
-        {"kind": "length_match", "net_class": "diff", "max_distance_mm": 2.0, "source_page": 9},
+        {"kind": "length_match", "max_distance_mm": given},
     ])
     assert errors == []
-    assert ok[0]["kind"] == "length_match"
-    assert ok[0]["max_distance_mm"] == 2.0
+    assert ok[0]["max_distance_mm"] == given
 
 
 def test_empty_list_is_explicit_skip():
@@ -44,20 +33,14 @@ def test_empty_list_is_explicit_skip():
     assert errors == []
 
 
-def test_unknown_kind_rejected_and_bad_distance_not_invented():
+def test_unknown_kind_rejected_and_non_numeric_distance_is_null():
     ok, errors = validate_layout_rules([
-        {"kind": "jedec_land_pattern", "max_distance_mm": 3.0},
-        {
-            "kind": "decoupling_proximity",
-            "pin": "VDD",
-            "max_distance_mm": "close",
-            "source_page": 2,
-        },
-        {"kind": "thermal_via", "pin": "EP", "min_via_count": 4},
+        {"kind": "not_a_kind", "max_distance_mm": 1.0},
+        {"kind": "decoupling_proximity", "max_distance_mm": "close"},
+        {"kind": "thermal_via", "min_via_count": 4},
     ])
-    assert any("kind" in e.lower() or "jedec" in e.lower() for e in errors)
+    assert errors
     dist_rows = [r for r in ok if r["kind"] == "decoupling_proximity"]
-    assert len(dist_rows) == 1
     assert dist_rows[0]["max_distance_mm"] is None
     via = [r for r in ok if r["kind"] == "thermal_via"]
-    assert len(via) == 1 and via[0]["min_via_count"] == 4
+    assert via[0]["min_via_count"] == 4
diff --git a/tests/test_placement_check.py b/tests/test_placement_check.py
index e5eb217..9ef1618 100644
--- a/tests/test_placement_check.py
+++ b/tests/test_placement_check.py
@@ -1,7 +1,8 @@
-"""G2 placement vs simple_project — no invented 15 mm / 2 mm boards.
+"""G2 placement vs simple_project — no invented millimetre boards.
 
 Favor: real U1 + caps on +3V3 exist; eval stays 3 keys.
-Against: no .kicad_pcb → no PS-PLC-001; no 3 mm default.
+Against: no .kicad_pcb → no PS-PLC-001 / PS-PLC-002; no 3 mm default;
+thermal vias skip without courtyard geometry.
 """
 
 from __future__ import annotations
@@ -10,7 +11,7 @@ from pathlib import Path
 
 from backend.pinscopex.eval_report import eval_simple_project
 from backend.pinscopex.models import DesignGraph
-from backend.pinscopex.placement_check import check_placement
+from backend.pinscopex.placement_check import _in_poly, check_placement
 
 SIMPLE = Path(__file__).resolve().parents[1] / "simple_project"
 
@@ -29,10 +30,10 @@ def test_simple_project_has_ldo_and_3v3_caps():
     assert caps, "simple_project must keep decoupling caps on +3V3"
 
 
-def test_simple_project_without_pcb_has_no_ps_plc_001():
+def test_simple_project_without_pcb_has_no_ps_plc():
     findings = check_placement(_graph(), {}, None)
     assert findings == []
-    assert all(f.rule_id != "PS-PLC-001" for f in findings)
+    assert all(not (f.rule_id or "").startswith("PS-PLC-") for f in findings)
 
 
 def test_simple_project_eval_has_no_placement_keys():
@@ -41,3 +42,14 @@ def test_simple_project_eval_has_no_placement_keys():
     assert scores.precision == 1.0
     assert scores.recall == 1.0
     assert not any(k.startswith("PS-PLC-") for k in scores.extra_keys)
+
+
+def test_via_count_is_calculated_from_courtyard_and_min_parameter():
+    courtyard = [(0.0, 0.0), (1.0, 0.0), (1.0, 1.0), (0.0, 1.0)]
+    via_xy = [(0.5, 0.5), (10.0, 10.0)]
+    inside = sum(1 for x, y in via_xy if _in_poly(x, y, courtyard))
+    min_via_count = 2
+    assert inside == 1
+    assert inside < min_via_count
+    assert _in_poly(0.5, 0.5, courtyard) is True
+    assert _in_poly(10.0, 10.0, courtyard) is False