diff --git a/lib/dns/db.c b/lib/dns/db.c
index 358ec710d8..7b575faaf2 100644
--- a/lib/dns/db.c
+++ b/lib/dns/db.c
@@ -668,7 +668,8 @@ dns_db_findrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
 	REQUIRE(node != NULL);
 	REQUIRE(DNS_RDATASET_VALID(rdataset));
 	REQUIRE(!dns_rdataset_isassociated(rdataset));
-	REQUIRE(covers == 0 || type == dns_rdatatype_rrsig);
+	REQUIRE(covers == dns_rdatatype_none || type == dns_rdatatype_rrsig ||
+		type == dns_rdatatype_sig);
 	REQUIRE(type != dns_rdatatype_any);
 	REQUIRE(sigrdataset == NULL ||
 		(DNS_RDATASET_VALID(sigrdataset) &&