diff --git a/src/data/AmendmentCenter.cpp b/src/data/AmendmentCenter.cpp
index 3bcebb589..2a3051c81 100644
--- a/src/data/AmendmentCenter.cpp
+++ b/src/data/AmendmentCenter.cpp
@@ -98,14 +98,26 @@ AmendmentCenter::AmendmentCenter(std::shared_ptr<data::BackendInterface> const&
                 .name = name,
                 .feature = Amendment::getAmendmentId(name),
                 .isSupportedByXRPL = support != ripple::AmendmentSupport::Unsupported,
-                .isSupportedByClio =
-                    rg::find(supportedAmendments(), name) != rg::end(supportedAmendments()),
+                .isSupportedByClio = rg::contains(supportedAmendments(), name),
                 .isRetired = support == ripple::AmendmentSupport::Retired
             };
         }),
         std::back_inserter(all_)
     );
 
+    // Mix in amendments that Clio registered but libXRPL no longer knows about (deleted upstream).
+    for (auto const& name : supportedAmendments()) {
+        if (not rg::contains(all_, name, &Amendment::name)) {
+            all_.push_back({
+                .name = name,
+                .feature = Amendment::getAmendmentId(name),
+                .isSupportedByXRPL = false,
+                .isSupportedByClio = true,
+                .isRetired = true,
+            });
+        }
+    }
+
     for (auto const& am : all_ | vs::filter([](auto const& am) { return am.isSupportedByClio; }))
         supported_.insert_or_assign(am.name, am);
 }
diff --git a/src/rpc/handlers/Feature.cpp b/src/rpc/handlers/Feature.cpp
index 3c152cd35..663593a26 100644
--- a/src/rpc/handlers/Feature.cpp
+++ b/src/rpc/handlers/Feature.cpp
@@ -64,7 +64,7 @@ FeatureHandler::process(FeatureHandler::Input const& input, Context const& ctx)
             return Output::Feature{
                 .name = feature.name,
                 .key = ripple::to_string(feature.feature),
-                .supported = feature.isSupportedByClio,
+                .supported = feature.isSupportedByClio and feature.isSupportedByXRPL,
             };
         }
     );
diff --git a/tests/unit/data/AmendmentCenterTests.cpp b/tests/unit/data/AmendmentCenterTests.cpp
index aa2834aa5..5dd1265a0 100644
--- a/tests/unit/data/AmendmentCenterTests.cpp
+++ b/tests/unit/data/AmendmentCenterTests.cpp
@@ -37,8 +37,9 @@ TEST_F(AmendmentCenterTest, AllAmendmentsFromLibXRPLAreSupported)
             << "XRPL amendment not supported by Clio: " << name;
     }
 
-    ASSERT_EQ(amendmentCenter.getSupported().size(), ripple::allAmendments().size());
-    ASSERT_EQ(amendmentCenter.getAll().size(), ripple::allAmendments().size());
+    // We support at least all the amendments currently exposed by libXRPL
+    ASSERT_GE(amendmentCenter.getSupported().size(), ripple::allAmendments().size());
+    ASSERT_GE(amendmentCenter.getAll().size(), ripple::allAmendments().size());
 }
 
 TEST_F(AmendmentCenterTest, Accessors)
@@ -147,6 +148,32 @@ TEST_F(AmendmentCenterTest, IsEnabledReturnsVectorOfFalseWhenNoAmendments)
     });
 }
 
+TEST_F(AmendmentCenterTest, DeletedLibXRPLAmendmentIsNotKnownToLibXRPL)
+{
+    // OwnerPaysFee was removed from libXRPL in 2.6.0; confirm it's not present upstream
+    EXPECT_FALSE(ripple::allAmendments().contains(std::string{Amendments::OwnerPaysFee}));
+}
+
+TEST_F(AmendmentCenterTest, DeletedLibXRPLAmendmentIsPresentInGetAllWithCorrectFlags)
+{
+    auto const& all = amendmentCenter.getAll();
+    auto const it = std::ranges::find(all, std::string{Amendments::OwnerPaysFee}, &Amendment::name);
+
+    ASSERT_NE(
+        it, all.end()
+    ) << "OwnerPaysFee must be present in getAll() even after libXRPL deleted it";
+    EXPECT_FALSE(it->isSupportedByXRPL);
+    EXPECT_TRUE(it->isSupportedByClio);
+    EXPECT_TRUE(it->isRetired);
+}
+
+TEST_F(AmendmentCenterTest, DeletedLibXRPLAmendmentIsSupportedByClio)
+{
+    // Clio still registers OwnerPaysFee so isSupported() and getSupported() must include it
+    EXPECT_TRUE(amendmentCenter.isSupported(Amendments::OwnerPaysFee));
+    EXPECT_TRUE(amendmentCenter.getSupported().contains(std::string{Amendments::OwnerPaysFee}));
+}
+
 TEST(AmendmentTest, GenerateAmendmentId)
 {
     // https://xrpl.org/known-amendments.html#disallowincoming refer to the published id
diff --git a/tests/unit/rpc/handlers/FeatureTests.cpp b/tests/unit/rpc/handlers/FeatureTests.cpp
index 144f3cfa3..93f3b72e6 100644
--- a/tests/unit/rpc/handlers/FeatureTests.cpp
+++ b/tests/unit/rpc/handlers/FeatureTests.cpp
@@ -14,6 +14,7 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 #include <xrpl/basics/base_uint.h>
+#include <xrpl/basics/strHex.h>
 
 #include <optional>
 #include <string>
@@ -386,6 +387,102 @@ TEST_F(RPCFeatureHandlerTest, BadFeaturePath)
     });
 }
 
+TEST_F(RPCFeatureHandlerTest, DeletedLibXRPLAmendmentQueryByNameReturnsSupportedFalse)
+{
+    auto const ownerPaysFeeKey =
+        ripple::to_string(data::Amendment::getAmendmentId(Amendments::OwnerPaysFee));
+    auto const all = std::vector<data::Amendment>{{
+        .name = Amendments::OwnerPaysFee,
+        .feature = data::Amendment::getAmendmentId(Amendments::OwnerPaysFee),
+        .isSupportedByXRPL = false,
+        .isSupportedByClio = true,
+        .isRetired = true,
+    }};
+    auto const keys = std::vector<data::AmendmentKey>{Amendments::OwnerPaysFee};
+    auto const enabled = std::vector<bool>{false};
+
+    EXPECT_CALL(*mockAmendmentCenterPtr_, getAll).WillOnce(testing::ReturnRef(all));
+    EXPECT_CALL(*mockAmendmentCenterPtr_, isEnabled(testing::_, keys, kSEQ))
+        .WillOnce(testing::Return(enabled));
+
+    auto const ledgerHeader = createLedgerHeader(kLEDGER_HASH, kSEQ);
+    EXPECT_CALL(*backend_, fetchLedgerBySequence).WillOnce(testing::Return(ledgerHeader));
+
+    auto const expectedOutput = fmt::format(
+        R"JSON({{
+            "{}": {{
+                "name": "OwnerPaysFee",
+                "enabled": false,
+                "supported": false
+            }},
+            "ledger_hash": "{}",
+            "ledger_index": {},
+            "validated": true
+        }})JSON",
+        ownerPaysFeeKey,
+        kLEDGER_HASH,
+        kSEQ
+    );
+
+    runSpawn([this, &expectedOutput](auto yield) {
+        auto const handler = AnyHandler{FeatureHandler{backend_, mockAmendmentCenterPtr_}};
+        auto const output = handler.process(
+            boost::json::parse(R"JSON({"feature": "OwnerPaysFee"})JSON"), Context{yield}
+        );
+
+        ASSERT_TRUE(output);
+        EXPECT_EQ(*output.result, boost::json::parse(expectedOutput));
+    });
+}
+
+TEST_F(RPCFeatureHandlerTest, DeletedLibXRPLAmendmentQueryByHashReturnsSupportedFalse)
+{
+    auto const ownerPaysFeeKey =
+        ripple::to_string(data::Amendment::getAmendmentId(Amendments::OwnerPaysFee));
+    auto const all = std::vector<data::Amendment>{{
+        .name = Amendments::OwnerPaysFee,
+        .feature = data::Amendment::getAmendmentId(Amendments::OwnerPaysFee),
+        .isSupportedByXRPL = false,
+        .isSupportedByClio = true,
+        .isRetired = true,
+    }};
+    auto const keys = std::vector<data::AmendmentKey>{Amendments::OwnerPaysFee};
+    auto const enabled = std::vector<bool>{true};
+
+    EXPECT_CALL(*mockAmendmentCenterPtr_, getAll).WillOnce(testing::ReturnRef(all));
+    EXPECT_CALL(*mockAmendmentCenterPtr_, isEnabled(testing::_, keys, kSEQ))
+        .WillOnce(testing::Return(enabled));
+
+    auto const ledgerHeader = createLedgerHeader(kLEDGER_HASH, kSEQ);
+    EXPECT_CALL(*backend_, fetchLedgerBySequence).WillOnce(testing::Return(ledgerHeader));
+
+    auto const expectedOutput = fmt::format(
+        R"JSON({{
+            "{}": {{
+                "name": "OwnerPaysFee",
+                "enabled": true,
+                "supported": false
+            }},
+            "ledger_hash": "{}",
+            "ledger_index": {},
+            "validated": true
+        }})JSON",
+        ownerPaysFeeKey,
+        kLEDGER_HASH,
+        kSEQ
+    );
+
+    runSpawn([this, &ownerPaysFeeKey, &expectedOutput](auto yield) {
+        auto const handler = AnyHandler{FeatureHandler{backend_, mockAmendmentCenterPtr_}};
+        auto const req =
+            boost::json::parse(fmt::format(R"JSON({{"feature": "{}"}})JSON", ownerPaysFeeKey));
+        auto const output = handler.process(req, Context{yield});
+
+        ASSERT_TRUE(output);
+        EXPECT_EQ(*output.result, boost::json::parse(expectedOutput));
+    });
+}
+
 TEST_F(RPCFeatureHandlerTest, SuccessPathWithMultipleResults)
 {
     auto const all = std::vector<data::Amendment>{