diff --git a/workspace-server/internal/handlers/workspace_broadcast.go b/workspace-server/internal/handlers/workspace_broadcast.go
index 27ce7a8ea..b213cfdfe 100644
--- a/workspace-server/internal/handlers/workspace_broadcast.go
+++ b/workspace-server/internal/handlers/workspace_broadcast.go
@@ -85,15 +85,15 @@ func (h *BroadcastHandler) Broadcast(c *gin.Context) {
 	var orgRootID string
 	err = db.DB.QueryRowContext(ctx, `
 		WITH RECURSIVE org_chain AS (
-			SELECT id, parent_id, id AS root_id
+			SELECT id, parent_id
 			FROM workspaces
 			WHERE id = $1
 			UNION ALL
-			SELECT w.id, w.parent_id, c.root_id
+			SELECT w.id, w.parent_id
 			FROM workspaces w
 			JOIN org_chain c ON w.id = c.parent_id
 		)
-		SELECT root_id FROM org_chain WHERE parent_id IS NULL LIMIT 1
+		SELECT id AS root_id FROM org_chain WHERE parent_id IS NULL LIMIT 1
 	`, senderID).Scan(&orgRootID)
 	if err != nil {
 		log.Printf("Broadcast: org root lookup for %s: %v", senderID, err)
diff --git a/workspace-server/internal/handlers/workspace_broadcast_org_root_integration_test.go b/workspace-server/internal/handlers/workspace_broadcast_org_root_integration_test.go
new file mode 100644
index 000000000..ad52c385e
--- /dev/null
+++ b/workspace-server/internal/handlers/workspace_broadcast_org_root_integration_test.go
@@ -0,0 +1,144 @@
+//go:build integration
+// +build integration
+
+// workspace_broadcast_org_root_integration_test.go — REAL Postgres
+// regression test for #1959: the Broadcast org-root recursive CTE.
+//
+// Run with:
+//
+//   INTEGRATION_DB_URL="postgres://postgres:test@localhost:55432/molecule?sslmode=disable" \
+//     go test -tags=integration ./internal/handlers/ -run Integration_BroadcastOrgRoot -v
+//
+// CI: piggybacks on .github/workflows/handlers-postgres-integration.yml
+// (path-filter includes workspace-server/internal/handlers/**).
+//
+// Why this is NOT a sqlmock test
+// ------------------------------
+// The unit tests in workspace_broadcast_test.go use sqlmock, which
+// returns whatever rows the test stubs — it CANNOT execute the
+// recursive CTE, so it cannot catch the #1959 bug where the anchor
+// pinned `id AS root_id` to the SENDER's own id and carried it
+// unchanged up the chain. With that bug a non-root sender resolved
+// ITSELF as the org root (wrong broadcast scoping). Only a real
+// Postgres can prove the corrected CTE resolves UP to the true
+// null-parent ancestor.
+//
+// The query under test is copied verbatim from Broadcast() in
+// workspace_broadcast.go; if that query changes, this test must be
+// updated in lockstep (it is the real-artifact gate for the fix).
+
+package handlers
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/google/uuid"
+	_ "github.com/lib/pq"
+)
+
+// orgRootCTE is the exact org-root resolution query from Broadcast().
+// Kept here verbatim so the test fails loudly if the handler regresses
+// to the #1959 sender-id-pinned form.
+const orgRootCTE = `
+	WITH RECURSIVE org_chain AS (
+		SELECT id, parent_id
+		FROM workspaces
+		WHERE id = $1
+		UNION ALL
+		SELECT w.id, w.parent_id
+		FROM workspaces w
+		JOIN org_chain c ON w.id = c.parent_id
+	)
+	SELECT id AS root_id FROM org_chain WHERE parent_id IS NULL LIMIT 1
+`
+
+func integrationDB_BroadcastOrgRoot(t *testing.T) *sql.DB {
+	t.Helper()
+	url := os.Getenv("INTEGRATION_DB_URL")
+	if url == "" {
+		t.Skip("INTEGRATION_DB_URL not set; skipping (see file header)")
+	}
+	conn, err := sql.Open("postgres", url)
+	if err != nil {
+		t.Fatalf("open: %v", err)
+	}
+	if err := conn.Ping(); err != nil {
+		t.Fatalf("ping: %v", err)
+	}
+	t.Cleanup(func() { conn.Close() })
+	return conn
+}
+
+// TestIntegration_BroadcastOrgRoot_NonRootSenderResolvesToRoot builds a
+// real three-level org chain in Postgres:
+//
+//	root  (parent_id = NULL)
+//	└── mid   (parent_id = root)
+//	    └── leaf  (parent_id = mid)   ← non-root sender
+//
+// and runs the handler's org-root CTE for each node. Every node — root,
+// mid, and leaf — MUST resolve to `root`. Under the #1959 bug the leaf
+// (and mid) resolved to themselves; this test pins the fix.
+func TestIntegration_BroadcastOrgRoot_NonRootSenderResolvesToRoot(t *testing.T) {
+	conn := integrationDB_BroadcastOrgRoot(t)
+	ctx := context.Background()
+
+	prefix := fmt.Sprintf("itest-bcastroot-%s", uuid.New().String()[:8])
+	t.Cleanup(func() {
+		if _, err := conn.ExecContext(ctx,
+			`DELETE FROM workspaces WHERE name LIKE $1`, prefix+"%"); err != nil {
+			t.Logf("cleanup (non-fatal): %v", err)
+		}
+	})
+
+	rootID := uuid.New().String()
+	midID := uuid.New().String()
+	leafID := uuid.New().String()
+
+	// root — parent_id NULL.
+	if _, err := conn.ExecContext(ctx, `
+		INSERT INTO workspaces (id, name, tier, runtime, status, parent_id)
+		VALUES ($1, $2, 2, 'claude-code', 'running', NULL)
+	`, rootID, prefix+"-root"); err != nil {
+		t.Fatalf("seed root: %v", err)
+	}
+	// mid — child of root.
+	if _, err := conn.ExecContext(ctx, `
+		INSERT INTO workspaces (id, name, tier, runtime, status, parent_id)
+		VALUES ($1, $2, 2, 'claude-code', 'running', $3)
+	`, midID, prefix+"-mid", rootID); err != nil {
+		t.Fatalf("seed mid: %v", err)
+	}
+	// leaf — child of mid (a non-root, non-direct-child sender).
+	if _, err := conn.ExecContext(ctx, `
+		INSERT INTO workspaces (id, name, tier, runtime, status, parent_id)
+		VALUES ($1, $2, 2, 'claude-code', 'running', $3)
+	`, leafID, prefix+"-leaf", midID); err != nil {
+		t.Fatalf("seed leaf: %v", err)
+	}
+
+	cases := []struct {
+		name     string
+		senderID string
+	}{
+		{"root sender resolves to itself", rootID},
+		{"mid sender resolves to root", midID},
+		{"leaf (deep non-root) sender resolves to root", leafID},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			var got string
+			if err := conn.QueryRowContext(ctx, orgRootCTE, tc.senderID).Scan(&got); err != nil {
+				t.Fatalf("org-root CTE for %s: %v", tc.senderID, err)
+			}
+			if got != rootID {
+				t.Errorf("org root for sender %s = %s; want %s (the true null-parent ancestor) — #1959 regression: a non-root sender resolved to the wrong root",
+					tc.senderID, got, rootID)
+			}
+		})
+	}
+}