diff --git a/src/gf.c b/src/gf.c
index 5b7a412c38255..a388e15d08742 100644
--- a/src/gf.c
+++ b/src/gf.c
@@ -78,9 +78,7 @@ static int cache_match_by_type(jl_value_t **types, size_t n, jl_tupletype_t *sig
             }
         }
         jl_value_t *a = types[i];
-        if (jl_is_datatype(a) && jl_is_datatype(decl) &&
-                 ((jl_datatype_t*)decl)->name == jl_type_type->name &&
-                 ((jl_datatype_t*)a   )->name == jl_type_type->name) {
+        if (jl_is_type_type(a) && jl_is_type_type(decl)) {
             jl_value_t *tp0 = jl_tparam0(decl);
             if (tp0 == (jl_value_t*)jl_typetype_tvar) {
                 // in the case of Type{T}, the types don't have
@@ -522,6 +520,22 @@ static jl_function_t *cache_method(jl_methtable_t *mt, jl_tupletype_t *type,
         }
         if (set_to_any || isstaged) {
         }
+        else if (jl_is_type_type(elt) && jl_is_typector(jl_tparam0(elt)) &&
+                 decl_i == (jl_value_t*)jl_typector_type) {
+            // TypeConstructors are problematic because they can be alternate
+            // representations of any type. If we matched this method because
+            // it matched the leaf type TypeConstructor, then don't
+            // cache something different since that doesn't necessarily actually apply
+            jl_svecset(newparams, i, jl_typector_type);
+        }
+        else if (jl_is_type_type(elt) && decl_i == (jl_value_t*)jl_datatype_type) {
+            // similarly, if we matched Type{T<:Any}::DataType,
+            // then we don't want to cache it that way
+            // since lookup will think we matched ::Type{T}
+            // and that is quite a different thing
+            jl_svecset(newparams, i, jl_datatype_type);
+            need_guard_entries = 1; // DataType has a UID so its precedence in the cache may be too high
+        }
         else if (jl_is_type_type(elt) && jl_is_type_type(jl_tparam0(elt)) &&
                  // give up on specializing static parameters for Type{Type{Type{...}}}
                  (jl_is_type_type(jl_tparam0(jl_tparam0(elt))) ||
diff --git a/test/core.jl b/test/core.jl
index d54065089cfeb..29a5447f2d87f 100644
--- a/test/core.jl
+++ b/test/core.jl
@@ -174,6 +174,25 @@ let T = TypeVar(:T, Tuple{Vararg{RangeIndex}}, true)
     @test  args_morespecific(t2, t1)
 end
 
+# issue #11840
+f11840(::Type) = "Type"
+f11840(::DataType) = "DataType"
+@test f11840(Type) == "DataType"
+@test f11840(AbstractVector) == "Type"
+
+g11840(::DataType) = 1
+g11840(::Type) = 2
+@test g11840(Vector.body) == 1
+@test g11840(Vector) == 2
+@test g11840(Vector.body) == 1
+
+h11840(::DataType) = '1'
+h11840(::Type) = '2'
+h11840(::TypeConstructor) = '3'
+@test h11840(Vector) == '3'
+@test h11840(Vector.body) == '1'
+@test h11840(Vector) == '3'
+
 # join
 @test typejoin(Int8,Int16) === Signed
 @test typejoin(Int,AbstractString) === Any