diff --git a/profile/sources.toml b/profile/sources.toml
index 78821fe..c57feb8 100644
--- a/profile/sources.toml
+++ b/profile/sources.toml
@@ -237,10 +237,16 @@ name = "NPR Politics"
 url = "https://feeds.npr.org/1014/rss.xml"
 bucket = "npr"
 
+# Ohio Capital Journal and Kentucky Lantern are both States Newsroom affiliates
+# and syndicate the same national desk -- they carried 10 byte-identical
+# headlines in a single poll, more than any other source pair in the config.
+# One bucket, so their shared copy reads as one confirmation rather than two.
+# They still contribute genuinely independent state-level reporting; the cost of
+# merging is slight under-counting there, which is the safe direction.
 [[source]]
 name = "Ohio Capital Journal"
 url = "https://ohiocapitaljournal.com/feed/"
-bucket = "ohio-capital-journal"
+bucket = "states-newsroom"
 poll_interval_secs = 3600
 
 [[source]]
@@ -258,7 +264,7 @@ poll_interval_secs = 3600
 [[source]]
 name = "Kentucky Lantern"
 url = "https://kentuckylantern.com/feed/"
-bucket = "kentucky-lantern"
+bucket = "states-newsroom"
 poll_interval_secs = 3600
 
 # ------------------------------------------------------------ italy / mexico --
diff --git a/tests/test_cluster.py b/tests/test_cluster.py
index 5d369ff..5b59831 100644
--- a/tests/test_cluster.py
+++ b/tests/test_cluster.py
@@ -79,3 +79,20 @@ def test_assignment_is_idempotent(con):
     assert a[0].cluster_id == b[0].cluster_id
     n = con.execute("SELECT COUNT(*) c FROM cluster_members").fetchone()["c"]
     assert n == 1, "re-assigning an item must not duplicate membership"
+
+
+def test_syndicated_partners_in_one_bucket_count_once(con):
+    """Regression: Ohio Capital Journal and Kentucky Lantern are both States
+    Newsroom and carried 10 identical headlines in one poll. Configured as
+    separate buckets they would have doubled the corroboration signal."""
+    v = unit(1, 0, 0)
+    for sid, name in (("sn1", "Ohio Capital Journal"), ("sn2", "Kentucky Lantern")):
+        store.upsert_source(con, id=sid, name=name, url=f"http://{sid}", kind="rss",
+                            bucket="states-newsroom", weight=1.0, prominence=0,
+                            enabled=1, poll_interval_secs=900)
+    rows = [add(con, "s1i", "sn1", "2026-01-01T00:00:00+00:00", "hs1"),
+            add(con, "s2i", "sn2", "2026-01-01T00:30:00+00:00", "hs2")]
+    out = cluster.assign(con, rows, {"hs1": v, "hs2": v})
+    assert out[0].cluster_id == out[1].cluster_id
+    assert cluster.bucket_count(con, out[0].cluster_id) == 1, (
+        "syndicated partners must not read as independent confirmation")