diff --git a/test/algorithms/overlay/multi_overlay_cases.hpp b/test/algorithms/overlay/multi_overlay_cases.hpp
index fea936d4f..956518323 100644
--- a/test/algorithms/overlay/multi_overlay_cases.hpp
+++ b/test/algorithms/overlay/multi_overlay_cases.hpp
@@ -475,4 +475,12 @@ static std::string ticket_11674[2] =
         "MULTIPOLYGON(((528 3218,528 2498,1734 1406,2556 1522,1734 1784,528 3218)),((4610 2288,5340 1178,5340 1832,4609 2289,4140 3002,2934 1574,2555 1521,2934 1400,4140 2582,4610 2288)))",
     };
 
+static std::string bug_21155501[2] =
+    {
+        "MULTIPOLYGON(((-8.3935546875 27.449790329784214,4.9658203125 18.729501999072138,11.8212890625 23.563987128451217,9.7119140625 25.48295117535531,9.8876953125 31.728167146023935,8.3056640625 32.99023555965106,8.5693359375 37.16031654673677,-1.8896484375 35.60371874069731,-0.5712890625 32.02670629333614,-8.9208984375 29.458731185355344,-8.3935546875 27.449790329784214)))",
+        "MULTIPOLYGON(((4.9658203125 18.729501999072138,-3.4868710311820115 24.246968623627644,8.3589904332912 33.833614418115445,8.3056640625 32.99023555965106,9.8876953125 31.728167146023935,9.7119140625 25.48295117535531,11.8212890625 23.563987128451217,4.9658203125 18.729501999072138)),((-3.88714525609152 24.508246314579743,-8.3935546875 27.449790329784214,-8.9208984375 29.458731185355344,-0.5712890625 32.02670629333614,-1.8896484375 35.60371874069731,8.5693359375 37.16031654673677,8.362166569827938 33.883846345901595,-3.88714525609152 24.508246314579743)))",
+    };
+
+
+
 #endif // BOOST_GEOMETRY_TEST_MULTI_OVERLAY_CASES_HPP
diff --git a/test/algorithms/set_operations/difference/difference.cpp b/test/algorithms/set_operations/difference/difference.cpp
index 5d90607aa..64a119c9c 100644
--- a/test/algorithms/set_operations/difference/difference.cpp
+++ b/test/algorithms/set_operations/difference/difference.cpp
@@ -40,33 +40,6 @@
 #endif
 
 
-template <typename CoordinateType>
-void test_bug21155501()
-{
-    typedef bg::model::point<CoordinateType,2,bg::cs::cartesian> point_type;
-    typedef bg::model::polygon
-        <
-        point_type, /*ClockWise*/false, /*Closed*/false
-        > polygon_type;
-    typedef bg::model::multi_polygon<polygon_type> multipolygon_type;
-
-    polygon_type g1;
-    bg::read_wkt("POLYGON((-8.3935546875 27.449790329784214,4.9658203125 18.729501999072138,11.8212890625 23.563987128451217,9.7119140625 25.48295117535531,9.8876953125 31.728167146023935,8.3056640625 32.99023555965106,8.5693359375 37.16031654673677,-1.8896484375 35.60371874069731,-0.5712890625 32.02670629333614,-8.9208984375 29.458731185355344,-8.3935546875 27.449790329784214))", g1);
-    multipolygon_type g2;
-    bg::read_wkt("MULTIPOLYGON(((4.9658203125 18.729501999072138,-3.4868710311820115 24.246968623627644,8.3589904332912 33.833614418115445,8.3056640625 32.99023555965106,9.8876953125 31.728167146023935,9.7119140625 25.48295117535531,11.8212890625 23.563987128451217,4.9658203125 18.729501999072138)),((-3.88714525609152 24.508246314579743,-8.3935546875 27.449790329784214,-8.9208984375 29.458731185355344,-0.5712890625 32.02670629333614,-1.8896484375 35.60371874069731,8.5693359375 37.16031654673677,8.362166569827938 33.883846345901595,-3.88714525609152 24.508246314579743)))", g2);
-    bg::correct(g1);
-    bg::correct(g2);
-
-    multipolygon_type diff12, diff21, sym_diff;
-    bg::difference(g1, g2, diff12);
-    bg::difference(g2, g1, diff21);
-    bg::sym_difference(g1, g2, sym_diff);
-
-    BOOST_CHECK(bg::is_valid(diff12));
-    BOOST_CHECK(bg::is_valid(diff21));
-    BOOST_CHECK(bg::is_valid(sym_diff));
-}
-
 template <typename P>
 void test_all()
 {
@@ -555,10 +528,6 @@ int test_main(int, char* [])
 
     test_specific<bg::model::d2::point_xy<int>, false, false>();
 
-#ifdef BOOST_GEOMETRY_TEST_INCLUDE_FAILING_TESTS
-    test_bug21155501<double>();
-#endif
-
 #if ! defined(BOOST_GEOMETRY_TEST_ONLY_ONE_TYPE)
     test_all<bg::model::d2::point_xy<float> >();
 
diff --git a/test/algorithms/set_operations/difference/difference_multi.cpp b/test/algorithms/set_operations/difference/difference_multi.cpp
index 9a758f73f..339902c70 100644
--- a/test/algorithms/set_operations/difference/difference_multi.cpp
+++ b/test/algorithms/set_operations/difference/difference_multi.cpp
@@ -146,6 +146,23 @@ void test_areal()
             tolerance(0.001));
 #endif
 
+    {
+        // Bug 21155501
+
+        // POSTGIS areas: 3.75893745345145, 2.5810000723917e-15
+
+        ut_settings settings;
+#ifdef BOOST_GEOMETRY_TEST_INCLUDE_FAILING_TESTS
+        settings.test_validity = true;
+#endif
+        test_one<Polygon, MultiPolygon, MultiPolygon>("bug_21155501",
+            bug_21155501[0], bug_21155501[1],
+                1, 9, 3.758937,
+                0, 0, 0.0,
+                settings);
+
+    }
+
     /* TODO: fix
     test_one<Polygon, MultiPolygon, MultiPolygon>("case_101_multi",
         case_101_multi[0], case_101_multi[1],