diff --git a/lib/go/camli/mysqlindexer/dbschema.go b/lib/go/camli/mysqlindexer/dbschema.go
index e54df81e9..5cb6f9163 100644
--- a/lib/go/camli/mysqlindexer/dbschema.go
+++ b/lib/go/camli/mysqlindexer/dbschema.go
@@ -18,7 +18,7 @@ package mysqlindexer
 
 import ()
 
-const requiredSchemaVersion = 11
+const requiredSchemaVersion = 12
 
 func SchemaVersion() int {
 	return requiredSchemaVersion
@@ -87,5 +87,13 @@ INDEX (permanode))`,
 		`CREATE TABLE meta (
 metakey VARCHAR(255) NOT NULL PRIMARY KEY,
 value VARCHAR(255) NOT NULL)`,
+
+		// Map from blobref (of ASCII armored public key) to keyid
+		`CREATE TABLE signerkeyid (
+blobref VARCHAR(128) NOT NULL,
+PRIMARY KEY (blobref),
+keyid   VARCHAR(128) NOT NULL,
+INDEX (keyid)
+)`,
 	}
 }
diff --git a/lib/go/camli/mysqlindexer/receive.go b/lib/go/camli/mysqlindexer/receive.go
index ddc412b1e..9c933a8de 100644
--- a/lib/go/camli/mysqlindexer/receive.go
+++ b/lib/go/camli/mysqlindexer/receive.go
@@ -196,6 +196,11 @@ func (mi *Indexer) populateClaim(client *mysql.Client, blobRef *blobref.BlobRef,
 		if vr.Verify() {
 			verifiedKeyId = vr.SignerKeyId
 			log.Printf("mysqlindex: verified claim %s from %s", blobRef, verifiedKeyId)
+
+			if err = execSQL(client, "INSERT IGNORE INTO signerkeyid (blobref, keyid) "+
+				"VALUES (?, ?)", vr.CamliSigner.String(), verifiedKeyId); err != nil {
+				return
+			}
 		} else {
 			log.Printf("mysqlindex: verification failure on claim %s: %v", blobRef, vr.Err)
 		}