diff --git a/include/bitcoin/database/impl/query/consensus/consensus_states.ipp b/include/bitcoin/database/impl/query/consensus/consensus_states.ipp
index 48df52c3e..867b95ac5 100644
--- a/include/bitcoin/database/impl/query/consensus/consensus_states.ipp
+++ b/include/bitcoin/database/impl/query/consensus/consensus_states.ipp
@@ -236,7 +236,8 @@ bool CLASS::set_block_confirmable(const header_link& link) NOEXCEPT
 TEMPLATE
 bool CLASS::set_block_unconfirmable(const header_link& link) NOEXCEPT
 {
-    return set_block_state(link, block_state::unconfirmable);
+    return !store_.mark_unconfirmable() ||
+        set_block_state(link, block_state::unconfirmable);
 }
 
 TEMPLATE
diff --git a/include/bitcoin/database/impl/store/store.ipp b/include/bitcoin/database/impl/store/store.ipp
index 12b83e41a..740b1d555 100644
--- a/include/bitcoin/database/impl/store/store.ipp
+++ b/include/bitcoin/database/impl/store/store.ipp
@@ -238,6 +238,12 @@ bool CLASS::turbo() const NOEXCEPT
     return configuration_.turbo;
 }
 
+TEMPLATE
+bool CLASS::mark_unconfirmable() const NOEXCEPT
+{
+    return configuration_.mark_unconfirmable;
+}
+
 TEMPLATE
 uint8_t CLASS::interval_depth() const NOEXCEPT
 {
diff --git a/include/bitcoin/database/query.hpp b/include/bitcoin/database/query.hpp
index 3ece0caaa..df946ce3f 100644
--- a/include/bitcoin/database/query.hpp
+++ b/include/bitcoin/database/query.hpp
@@ -582,6 +582,10 @@ class query
     bool set_signatures(const threshold& group, size_t set,
         const header_link& link) NOEXCEPT;
 
+    // TODO:
+    bool purge_signatures() NOEXCEPT { return {}; };
+    bool verify_signatures(header_links& ) NOEXCEPT { return {}; };
+
     /// Confirmation.
     /// -----------------------------------------------------------------------
     /// These are not used in consensus confirmation.
diff --git a/include/bitcoin/database/settings.hpp b/include/bitcoin/database/settings.hpp
index 5a7371db1..6909744a9 100644
--- a/include/bitcoin/database/settings.hpp
+++ b/include/bitcoin/database/settings.hpp
@@ -42,6 +42,9 @@ struct BCD_API settings
     /// Enable concurrency in individual client-server queries.
     bool turbo{ false };
 
+    /// Mark blocks as unconfirmable (disorganize vs. stall).
+    bool mark_unconfirmable{ true };
+
     /// Depth of electrum merkle tree interval caching.
     uint16_t interval_depth{ max_uint8 };
 
diff --git a/include/bitcoin/database/store.hpp b/include/bitcoin/database/store.hpp
index b2a9187ab..73e4a3be8 100644
--- a/include/bitcoin/database/store.hpp
+++ b/include/bitcoin/database/store.hpp
@@ -86,6 +86,9 @@ class store
     /// Allows full throttle concurrent query execution (may use 100% CPU).
     bool turbo() const NOEXCEPT;
 
+    /// Mark blocks as unconfirmable (disorganize vs. stall), configuration.
+    bool mark_unconfirmable() const NOEXCEPT;
+
     /// Depth of electrum merkle tree interval caching.
     uint8_t interval_depth() const NOEXCEPT;
 
diff --git a/test/settings.cpp b/test/settings.cpp
index aa0cffc79..390640b13 100644
--- a/test/settings.cpp
+++ b/test/settings.cpp
@@ -24,6 +24,7 @@ BOOST_AUTO_TEST_CASE(settings__construct__default__expected)
 {
     database::settings configuration;
     BOOST_REQUIRE_EQUAL(configuration.turbo, false);
+    BOOST_REQUIRE_EQUAL(configuration.mark_unconfirmable, true);
     BOOST_REQUIRE_EQUAL(configuration.interval_depth, 255u);
     BOOST_REQUIRE_EQUAL(configuration.path, "bitcoin");