diff --git a/roadmap-planner/backend/config.example.yaml b/roadmap-planner/backend/config.example.yaml
index a4358f19..6748ef0a 100644
--- a/roadmap-planner/backend/config.example.yaml
+++ b/roadmap-planner/backend/config.example.yaml
@@ -49,6 +49,15 @@ metrics:
     path: "/metrics"
     namespace: "roadmap"         # Metric prefix: roadmap_dora_*
 
+  # Components dropped from all component dimensions (D6 — v3-era
+  # plugins must not dilute v4 team metrics). Exact component names as
+  # parsed from version names (e.g. katanomi-v3.1.0 -> katanomi).
+  exclude_plugins:
+    - katanomi
+    - knative
+    - jenkins
+    - tekton-operator
+
   filters:
     - name: "releases"
       enabled: true
diff --git a/roadmap-planner/backend/internal/config/config.go b/roadmap-planner/backend/internal/config/config.go
index 4f868b76..04d8e533 100644
--- a/roadmap-planner/backend/internal/config/config.go
+++ b/roadmap-planner/backend/internal/config/config.go
@@ -274,6 +274,22 @@ type Metrics struct {
 	Prometheus         PrometheusConfig `mapstructure:"prometheus"`
 	Filters            []OptionsConfig  `mapstructure:"filters"`
 	Calculators        []OptionsConfig  `mapstructure:"calculators"`
+	// ExcludePlugins lists component names dropped from all component
+	// dimensions (releases and issue components) during collection.
+	// Implements plan D6 — v3-era plugins (katanomi, knative, jenkins,
+	// tekton-operator) must not dilute v4 team metrics. Exact match.
+	ExcludePlugins []string `mapstructure:"exclude_plugins"`
+}
+
+// IsPluginExcluded reports whether a component name is in the
+// exclude_plugins list.
+func (c *Metrics) IsPluginExcluded(name string) bool {
+	for _, p := range c.ExcludePlugins {
+		if p == name {
+			return true
+		}
+	}
+	return false
 }
 
 // PrometheusConfig represents Prometheus exporter configuration
diff --git a/roadmap-planner/backend/internal/metrics/calculators/patch_ratio.go b/roadmap-planner/backend/internal/metrics/calculators/patch_ratio.go
index 9c8fcc92..22ca62e1 100644
--- a/roadmap-planner/backend/internal/metrics/calculators/patch_ratio.go
+++ b/roadmap-planner/backend/internal/metrics/calculators/patch_ratio.go
@@ -70,7 +70,9 @@ func (c *PatchRatioCalculator) Calculate(ctx context.Context, data *models.Calcu
 
 		component := release.Component
 		if component == "" {
-			component = "unknown"
+			// Collector drops these, but guard here too: an unparsable
+			// version name is not a component bucket.
+			continue
 		}
 
 		// Apply component filter if specified
diff --git a/roadmap-planner/backend/internal/metrics/calculators/patch_ratio_test.go b/roadmap-planner/backend/internal/metrics/calculators/patch_ratio_test.go
new file mode 100644
index 00000000..03ccf8bf
--- /dev/null
+++ b/roadmap-planner/backend/internal/metrics/calculators/patch_ratio_test.go
@@ -0,0 +1,51 @@
+/*
+Copyright 2024 The AlaudaDevops Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+*/
+
+package calculators
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/AlaudaDevops/toolbox/roadmap-planner/backend/internal/metrics/models"
+)
+
+// TestPatchRatio_SkipsEmptyComponentReleases locks in the
+// invalid-component guard: a release whose name did not parse
+// (Component == "") used to be bucketed under "unknown"; it must now be
+// skipped entirely so legacy version names like "0.3" never surface as
+// component buckets.
+func TestPatchRatio_SkipsEmptyComponentReleases(t *testing.T) {
+	c := NewPatchRatioCalculator(nil)
+
+	relDate := time.Date(2026, 5, 10, 12, 0, 0, 0, time.UTC)
+	ctx := &models.CalculationContext{
+		Releases: []models.EnrichedRelease{
+			{ID: "v1", Name: "argo-cd-2.9.1", Component: "argo-cd", Released: true, ReleaseDate: relDate, Type: "patch"},
+			{ID: "v2", Name: "0.3", Component: "", Released: true, ReleaseDate: relDate, Type: "unknown"},
+		},
+		TimeRange: models.TimeRange{
+			Start: relDate.AddDate(0, -6, 0),
+			End:   relDate.AddDate(0, 1, 0),
+		},
+	}
+
+	results, err := c.Calculate(context.Background(), ctx)
+	if err != nil {
+		t.Fatalf("Calculate: %v", err)
+	}
+	if len(results) != 1 {
+		t.Fatalf("len(results) = %d, want 1 (only the valid component)", len(results))
+	}
+	if got := results[0].Labels["component"]; got != "argo-cd" {
+		t.Errorf("component = %q, want argo-cd (empty-component release must not bucket as %q)", got, got)
+	}
+}
diff --git a/roadmap-planner/backend/internal/metrics/calculators/release_frequency.go b/roadmap-planner/backend/internal/metrics/calculators/release_frequency.go
index bb75098a..7e2c0056 100644
--- a/roadmap-planner/backend/internal/metrics/calculators/release_frequency.go
+++ b/roadmap-planner/backend/internal/metrics/calculators/release_frequency.go
@@ -62,7 +62,9 @@ func (c *ReleaseFrequencyCalculator) Calculate(ctx context.Context, data *models
 
 		component := release.Component
 		if component == "" {
-			component = "unknown"
+			// Collector drops these, but guard here too: an unparsable
+			// version name is not a component bucket.
+			continue
 		}
 
 		// Apply component filter if specified
diff --git a/roadmap-planner/backend/internal/metrics/calculators/release_frequency_test.go b/roadmap-planner/backend/internal/metrics/calculators/release_frequency_test.go
new file mode 100644
index 00000000..56e823e0
--- /dev/null
+++ b/roadmap-planner/backend/internal/metrics/calculators/release_frequency_test.go
@@ -0,0 +1,51 @@
+/*
+Copyright 2024 The AlaudaDevops Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+*/
+
+package calculators
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/AlaudaDevops/toolbox/roadmap-planner/backend/internal/metrics/models"
+)
+
+// TestReleaseFrequency_SkipsEmptyComponentReleases locks in the
+// invalid-component guard: a release whose name did not parse
+// (Component == "") used to be bucketed under "unknown"; it must now be
+// skipped entirely so legacy version names like "0.3" never surface as
+// component buckets.
+func TestReleaseFrequency_SkipsEmptyComponentReleases(t *testing.T) {
+	c := NewReleaseFrequencyCalculator(nil)
+
+	relDate := time.Date(2026, 5, 10, 12, 0, 0, 0, time.UTC)
+	ctx := &models.CalculationContext{
+		Releases: []models.EnrichedRelease{
+			{ID: "v1", Name: "argo-cd-2.9.0", Component: "argo-cd", Released: true, ReleaseDate: relDate, Type: "minor"},
+			{ID: "v2", Name: "0.3", Component: "", Released: true, ReleaseDate: relDate, Type: "unknown"},
+		},
+		TimeRange: models.TimeRange{
+			Start: relDate.AddDate(0, -3, 0),
+			End:   relDate.AddDate(0, 1, 0),
+		},
+	}
+
+	results, err := c.Calculate(context.Background(), ctx)
+	if err != nil {
+		t.Fatalf("Calculate: %v", err)
+	}
+	if len(results) != 1 {
+		t.Fatalf("len(results) = %d, want 1 (only the valid component)", len(results))
+	}
+	if got := results[0].Labels["component"]; got != "argo-cd" {
+		t.Errorf("component = %q, want argo-cd (empty-component release must not bucket as %q)", got, got)
+	}
+}
diff --git a/roadmap-planner/backend/internal/metrics/collector.go b/roadmap-planner/backend/internal/metrics/collector.go
index e1b05a01..e3edc277 100644
--- a/roadmap-planner/backend/internal/metrics/collector.go
+++ b/roadmap-planner/backend/internal/metrics/collector.go
@@ -159,10 +159,54 @@ func (c *Collector) fetchReleases(ctx context.Context) ([]models.EnrichedRelease
 		c.logger.Debug("Filtered releases")
 	}
 
+	releases = c.dropInvalidComponentReleases(releases)
+
 	c.logger.Debug("Fetched releases", zap.Int("count", len(releases)), zap.Int("original", originalCount))
 	return releases, nil
 }
 
+// dropInvalidComponentReleases removes releases that must not feed any
+// component dimension: names that do not parse to component-X.Y.Z
+// (Component is empty — legacy names like "0.3", "v2.1") and components
+// in metrics.exclude_plugins (D6 — v3-era plugins). Dropping here keeps
+// every calculator clean without per-calculator filtering, and also
+// removes the releases from the versionDates maps so issues linked only
+// to invalid versions stay out of release-scoped metrics.
+func (c *Collector) dropInvalidComponentReleases(releases []models.EnrichedRelease) []models.EnrichedRelease {
+	kept := make([]models.EnrichedRelease, 0, len(releases))
+	dropped := make([]string, 0)
+	for _, r := range releases {
+		if r.Component == "" || c.config.IsPluginExcluded(r.Component) {
+			dropped = append(dropped, r.Name)
+			continue
+		}
+		kept = append(kept, r)
+	}
+	if len(dropped) > 0 {
+		c.logger.Debug("Dropped releases with invalid or excluded components",
+			zap.Int("count", len(dropped)), zap.Strings("names", dropped))
+	}
+	return kept
+}
+
+// dropExcludedComponents removes metrics.exclude_plugins entries from an
+// issue's component list (both Jira Component fields and components
+// extracted from version names) so D6 plugins disappear from issue-based
+// component dimensions (cycle_time, time_to_patch).
+func (c *Collector) dropExcludedComponents(components []string) []string {
+	if len(c.config.ExcludePlugins) == 0 || len(components) == 0 {
+		return components
+	}
+	kept := make([]string, 0, len(components))
+	for _, comp := range components {
+		if c.config.IsPluginExcluded(comp) {
+			continue
+		}
+		kept = append(kept, comp)
+	}
+	return kept
+}
+
 // enrichRelease converts a basic Version to an EnrichedRelease
 func (c *Collector) enrichRelease(v baseModels.Version) models.EnrichedRelease {
 	release := models.EnrichedRelease{
@@ -205,8 +249,11 @@ func parseVersionName(name string) (component string, major, minor, patch int) {
 		return
 	}
 
-	// If no version pattern found, the whole name is the component
-	component = name
+	// No version pattern found — the name does not identify a component.
+	// Legacy names like "0.3", "v2.1" or "1.0" used to fall back to the
+	// whole name here, which polluted every per-component metric with
+	// bogus component buckets. Return empty so collectors/calculators
+	// drop the release from component dimensions.
 	return
 }
 
@@ -286,6 +333,7 @@ func (c *Collector) fetchEpics(ctx context.Context) ([]models.EnrichedIssue, err
 				}
 			}
 		}
+		enriched.Components = c.dropExcludedComponents(enriched.Components)
 
 		epics = append(epics, enriched)
 	}
@@ -355,6 +403,7 @@ func (c *Collector) fetchIssues(ctx context.Context) ([]models.EnrichedIssue, er
 				}
 			}
 		}
+		enriched.Components = c.dropExcludedComponents(enriched.Components)
 		issues = append(issues, enriched)
 	}
 
diff --git a/roadmap-planner/backend/internal/metrics/collector_test.go b/roadmap-planner/backend/internal/metrics/collector_test.go
new file mode 100644
index 00000000..3b4307c2
--- /dev/null
+++ b/roadmap-planner/backend/internal/metrics/collector_test.go
@@ -0,0 +1,105 @@
+/*
+Copyright 2024 The AlaudaDevops Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+*/
+
+package metrics
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/AlaudaDevops/toolbox/roadmap-planner/backend/internal/config"
+	"github.com/AlaudaDevops/toolbox/roadmap-planner/backend/internal/metrics/models"
+	"go.uber.org/zap"
+)
+
+// TestParseVersionName guards the invalid-component fix: names that do
+// not carry a component-X.Y.Z pattern must return an empty component
+// instead of the legacy whole-name fallback that polluted every
+// per-component metric with buckets like "0.3" or "v2.1".
+func TestParseVersionName(t *testing.T) {
+	cases := []struct {
+		name                string
+		wantComponent       string
+		major, minor, patch int
+	}{
+		// Valid names — component extracted.
+		{"argo-cd-2.9.0", "argo-cd", 2, 9, 0},
+		{"tektoncd-operator-v4.6.3", "tektoncd-operator", 4, 6, 3},
+		{"harbor 1.2.3", "harbor", 1, 2, 3},
+		{"connectors-operator-1.2.3-rc1", "connectors-operator", 1, 2, 3},
+		// Legacy / invalid names — no component.
+		{"0.3", "", 0, 0, 0},
+		{"v2.1", "", 0, 0, 0},
+		{"1.0", "", 0, 0, 0},
+		{"Sprint 2024", "", 0, 0, 0},
+		{"", "", 0, 0, 0},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			component, major, minor, patch := parseVersionName(tc.name)
+			if component != tc.wantComponent || major != tc.major || minor != tc.minor || patch != tc.patch {
+				t.Errorf("parseVersionName(%q) = (%q, %d, %d, %d), want (%q, %d, %d, %d)",
+					tc.name, component, major, minor, patch,
+					tc.wantComponent, tc.major, tc.minor, tc.patch)
+			}
+		})
+	}
+}
+
+// TestDropInvalidComponentReleases covers both invalid classes: empty
+// component (unparsable version name) and metrics.exclude_plugins (D6 —
+// v3-era plugins).
+func TestDropInvalidComponentReleases(t *testing.T) {
+	c := &Collector{
+		config: &config.Metrics{
+			ExcludePlugins: []string{"katanomi", "knative", "jenkins", "tekton-operator"},
+		},
+		logger: zap.NewNop(),
+	}
+	in := []models.EnrichedRelease{
+		{Name: "tektoncd-operator-v4.6.3", Component: "tektoncd-operator"},
+		{Name: "0.3", Component: ""},                                // unparsable → dropped
+		{Name: "katanomi-v3.1.0", Component: "katanomi"},            // D6 → dropped
+		{Name: "tekton-operator-v3.20.0", Component: "tekton-operator"}, // D6 → dropped
+		{Name: "argo-cd-2.9.0", Component: "argo-cd"},
+	}
+	got := c.dropInvalidComponentReleases(in)
+	want := []string{"tektoncd-operator", "argo-cd"}
+	gotComponents := make([]string, 0, len(got))
+	for _, r := range got {
+		gotComponents = append(gotComponents, r.Component)
+	}
+	if !reflect.DeepEqual(gotComponents, want) {
+		t.Errorf("kept components = %v, want %v", gotComponents, want)
+	}
+}
+
+// TestDropExcludedComponents covers the issue-side path: D6 plugins are
+// removed from issue component lists while everything else is kept.
+func TestDropExcludedComponents(t *testing.T) {
+	c := &Collector{config: &config.Metrics{ExcludePlugins: []string{"katanomi", "jenkins"}}}
+	cases := []struct {
+		name string
+		in   []string
+		want []string
+	}{
+		{"mixed", []string{"katanomi", "tektoncd-operator", "jenkins"}, []string{"tektoncd-operator"}},
+		{"all excluded", []string{"katanomi"}, []string{}},
+		{"none excluded", []string{"argo-cd"}, []string{"argo-cd"}},
+		{"empty", nil, nil},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := c.dropExcludedComponents(tc.in); !reflect.DeepEqual(got, tc.want) {
+				t.Errorf("dropExcludedComponents(%v) = %v, want %v", tc.in, got, tc.want)
+			}
+		})
+	}
+}