diff --git a/internal/gen/tests/example/v1/validations.pb.go b/internal/gen/tests/example/v1/validations.pb.go
index d747d34..4917f40 100644
--- a/internal/gen/tests/example/v1/validations.pb.go
+++ b/internal/gen/tests/example/v1/validations.pb.go
@@ -651,87 +651,6 @@ func (x *FieldOfTypeAny) GetAny() *anypb.Any {
 	return nil
 }
 
-type RequiredOneof struct {
-	state         protoimpl.MessageState
-	sizeCache     protoimpl.SizeCache
-	unknownFields protoimpl.UnknownFields
-
-	// Types that are assignable to RequiredOneof:
-	//
-	//	*RequiredOneof_Fld_1
-	//	*RequiredOneof_Fld_2
-	RequiredOneof isRequiredOneof_RequiredOneof `protobuf_oneof:"required_oneof"`
-}
-
-func (x *RequiredOneof) Reset() {
-	*x = RequiredOneof{}
-	if protoimpl.UnsafeEnabled {
-		mi := &file_tests_example_v1_validations_proto_msgTypes[11]
-		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
-		ms.StoreMessageInfo(mi)
-	}
-}
-
-func (x *RequiredOneof) String() string {
-	return protoimpl.X.MessageStringOf(x)
-}
-
-func (*RequiredOneof) ProtoMessage() {}
-
-func (x *RequiredOneof) ProtoReflect() protoreflect.Message {
-	mi := &file_tests_example_v1_validations_proto_msgTypes[11]
-	if protoimpl.UnsafeEnabled && x != nil {
-		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
-		if ms.LoadMessageInfo() == nil {
-			ms.StoreMessageInfo(mi)
-		}
-		return ms
-	}
-	return mi.MessageOf(x)
-}
-
-// Deprecated: Use RequiredOneof.ProtoReflect.Descriptor instead.
-func (*RequiredOneof) Descriptor() ([]byte, []int) {
-	return file_tests_example_v1_validations_proto_rawDescGZIP(), []int{11}
-}
-
-func (m *RequiredOneof) GetRequiredOneof() isRequiredOneof_RequiredOneof {
-	if m != nil {
-		return m.RequiredOneof
-	}
-	return nil
-}
-
-func (x *RequiredOneof) GetFld_1() string {
-	if x, ok := x.GetRequiredOneof().(*RequiredOneof_Fld_1); ok {
-		return x.Fld_1
-	}
-	return ""
-}
-
-func (x *RequiredOneof) GetFld_2() *fieldmaskpb.FieldMask {
-	if x, ok := x.GetRequiredOneof().(*RequiredOneof_Fld_2); ok {
-		return x.Fld_2
-	}
-	return nil
-}
-
-type isRequiredOneof_RequiredOneof interface {
-	isRequiredOneof_RequiredOneof()
-}
-
-type RequiredOneof_Fld_1 struct {
-	Fld_1 string `protobuf:"bytes,1,opt,name=fld_1,json=fld1,proto3,oneof"`
-}
-
-type RequiredOneof_Fld_2 struct {
-	Fld_2 *fieldmaskpb.FieldMask `protobuf:"bytes,2,opt,name=fld_2,json=fld2,proto3,oneof"`
-}
-
-func (*RequiredOneof_Fld_1) isRequiredOneof_RequiredOneof() {}
-
-func (*RequiredOneof_Fld_2) isRequiredOneof_RequiredOneof() {}
-
 var File_tests_example_v1_validations_proto protoreflect.FileDescriptor
 
 var file_tests_example_v1_validations_proto_rawDesc = []byte{
@@ -875,28 +794,21 @@ var file_tests_example_v1_validations_proto_rawDesc = []byte{
 	0x79, 0x5f, 0x74, 0x79, 0x70, 0x65, 0x12, 0x16, 0x74, 0x68, 0x69, 0x73, 0x20, 0x73, 0x68, 0x6f,
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-	0x5f, 0x32, 0x18, 0x02, 0x20, 0x01, 0x28, 0x0b, 0x32, 0x1a, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c,
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-	0x50, 0x01, 0x5a, 0x4c, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x62,
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-	0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
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+	0x64, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x73, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01, 0x5a, 0x4c,
+	0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x62, 0x75, 0x66, 0x62, 0x75,
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+	0x61, 0x6d, 0x70, 0x6c, 0x65, 0x5c, 0x56, 0x31, 0xe2, 0x02, 0x1c, 0x54, 0x65, 0x73, 0x74, 0x73,
+	0x5c, 0x45, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x5c, 0x56, 0x31, 0x5c, 0x47, 0x50, 0x42, 0x4d,
+	0x65, 0x74, 0x61, 0x64, 0x61, 0x74, 0x61, 0xea, 0x02, 0x12, 0x54, 0x65, 0x73, 0x74, 0x73, 0x3a,
+	0x3a, 0x45, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x3a, 0x3a, 0x56, 0x31, 0x62, 0x06, 0x70, 0x72,
+	0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
@@ -911,7 +823,7 @@ func file_tests_example_v1_validations_proto_rawDescGZIP() []byte {
 	return file_tests_example_v1_validations_proto_rawDescData
 }
 
-var file_tests_example_v1_validations_proto_msgTypes = make([]protoimpl.MessageInfo, 15)
+var file_tests_example_v1_validations_proto_msgTypes = make([]protoimpl.MessageInfo, 14)
 var file_tests_example_v1_validations_proto_goTypes = []interface{}{
 	(*HasMsgExprs)(nil),                             // 0: tests.example.v1.HasMsgExprs
 	(*SelfRecursive)(nil),                           // 1: tests.example.v1.SelfRecursive
@@ -924,13 +836,12 @@ var file_tests_example_v1_validations_proto_goTypes = []interface{}{
 	(*MultipleStepsTransitiveFieldConstraints)(nil), // 8: tests.example.v1.MultipleStepsTransitiveFieldConstraints
 	(*Simple)(nil),                                  // 9: tests.example.v1.Simple
 	(*FieldOfTypeAny)(nil),                          // 10: tests.example.v1.FieldOfTypeAny
-	(*RequiredOneof)(nil),                           // 11: tests.example.v1.RequiredOneof
-	nil,                                             // 12: tests.example.v1.MsgHasMap.Int32mapEntry
-	nil,                                             // 13: tests.example.v1.MsgHasMap.StringMapEntry
-	nil,                                             // 14: tests.example.v1.MsgHasMap.MessageMapEntry
-	(*fieldmaskpb.FieldMask)(nil),                   // 15: google.protobuf.FieldMask
-	(*apipb.Api)(nil),                               // 16: google.protobuf.Api
-	(*anypb.Any)(nil),                               // 17: google.protobuf.Any
+	nil,                                             // 11: tests.example.v1.MsgHasMap.Int32mapEntry
+	nil,                                             // 12: tests.example.v1.MsgHasMap.StringMapEntry
+	nil,                                             // 13: tests.example.v1.MsgHasMap.MessageMapEntry
+	(*fieldmaskpb.FieldMask)(nil),                   // 14: google.protobuf.FieldMask
+	(*apipb.Api)(nil),                               // 15: google.protobuf.Api
+	(*anypb.Any)(nil),                               // 16: google.protobuf.Any
 }
 var file_tests_example_v1_validations_proto_depIdxs = []int32{
 	1,  // 0: tests.example.v1.SelfRecursive.turtle:type_name -> tests.example.v1.SelfRecursive
@@ -938,19 +849,18 @@ var file_tests_example_v1_validations_proto_depIdxs = []int32{
 	2,  // 2: tests.example.v1.LoopRecursiveB.a:type_name -> tests.example.v1.LoopRecursiveA
 	0,  // 3: tests.example.v1.MsgHasOneof.msg:type_name -> tests.example.v1.HasMsgExprs
 	0,  // 4: tests.example.v1.MsgHasRepeated.z:type_name -> tests.example.v1.HasMsgExprs
-	12, // 5: tests.example.v1.MsgHasMap.int32map:type_name -> tests.example.v1.MsgHasMap.Int32mapEntry
-	13, // 6: tests.example.v1.MsgHasMap.string_map:type_name -> tests.example.v1.MsgHasMap.StringMapEntry
-	14, // 7: tests.example.v1.MsgHasMap.message_map:type_name -> tests.example.v1.MsgHasMap.MessageMapEntry
-	15, // 8: tests.example.v1.TransitiveFieldConstraint.mask:type_name -> google.protobuf.FieldMask
-	16, // 9: tests.example.v1.MultipleStepsTransitiveFieldConstraints.api:type_name -> google.protobuf.Api
-	17, // 10: tests.example.v1.FieldOfTypeAny.any:type_name -> google.protobuf.Any
-	15, // 11: tests.example.v1.RequiredOneof.fld_2:type_name -> google.protobuf.FieldMask
-	2,  // 12: tests.example.v1.MsgHasMap.MessageMapEntry.value:type_name -> tests.example.v1.LoopRecursiveA
-	13, // [13:13] is the sub-list for method output_type
-	13, // [13:13] is the sub-list for method input_type
-	13, // [13:13] is the sub-list for extension type_name
-	13, // [13:13] is the sub-list for extension extendee
-	0,  // [0:13] is the sub-list for field type_name
+	11, // 5: tests.example.v1.MsgHasMap.int32map:type_name -> tests.example.v1.MsgHasMap.Int32mapEntry
+	12, // 6: tests.example.v1.MsgHasMap.string_map:type_name -> tests.example.v1.MsgHasMap.StringMapEntry
+	13, // 7: tests.example.v1.MsgHasMap.message_map:type_name -> tests.example.v1.MsgHasMap.MessageMapEntry
+	14, // 8: tests.example.v1.TransitiveFieldConstraint.mask:type_name -> google.protobuf.FieldMask
+	15, // 9: tests.example.v1.MultipleStepsTransitiveFieldConstraints.api:type_name -> google.protobuf.Api
+	16, // 10: tests.example.v1.FieldOfTypeAny.any:type_name -> google.protobuf.Any
+	2,  // 11: tests.example.v1.MsgHasMap.MessageMapEntry.value:type_name -> tests.example.v1.LoopRecursiveA
+	12, // [12:12] is the sub-list for method output_type
+	12, // [12:12] is the sub-list for method input_type
+	12, // [12:12] is the sub-list for extension type_name
+	12, // [12:12] is the sub-list for extension extendee
+	0,  // [0:12] is the sub-list for field type_name
 }
 
 func init() { file_tests_example_v1_validations_proto_init() }
@@ -1091,35 +1001,19 @@ func file_tests_example_v1_validations_proto_init() {
 				return nil
 			}
 		}
-		file_tests_example_v1_validations_proto_msgTypes[11].Exporter = func(v interface{}, i int) interface{} {
-			switch v := v.(*RequiredOneof); i {
-			case 0:
-				return &v.state
-			case 1:
-				return &v.sizeCache
-			case 2:
-				return &v.unknownFields
-			default:
-				return nil
-			}
-		}
 	}
 	file_tests_example_v1_validations_proto_msgTypes[4].OneofWrappers = []interface{}{
 		(*MsgHasOneof_X)(nil),
 		(*MsgHasOneof_Y)(nil),
 		(*MsgHasOneof_Msg)(nil),
 	}
-	file_tests_example_v1_validations_proto_msgTypes[11].OneofWrappers = []interface{}{
-		(*RequiredOneof_Fld_1)(nil),
-		(*RequiredOneof_Fld_2)(nil),
-	}
 	type x struct{}
 	out := protoimpl.TypeBuilder{
 		File: protoimpl.DescBuilder{
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_tests_example_v1_validations_proto_rawDesc,
 			NumEnums:      0,
-			NumMessages:   15,
+			NumMessages:   14,
 			NumExtensions: 0,
 			NumServices:   0,
 		},
diff --git a/proto/tests/example/v1/validations.proto b/proto/tests/example/v1/validations.proto
index 708b9d2..f5b7307 100644
--- a/proto/tests/example/v1/validations.proto
+++ b/proto/tests/example/v1/validations.proto
@@ -153,11 +153,3 @@ message FieldOfTypeAny {
     expression: "this == this"
   }];
 }
-
-message RequiredOneof {
-  oneof required_oneof {
-    option (buf.validate.oneof).required = true;
-    string fld_1 = 1;
-    google.protobuf.FieldMask fld_2 = 2;
-  }
-}
diff --git a/validator_test.go b/validator_test.go
index e11ee73..d2aeff9 100644
--- a/validator_test.go
+++ b/validator_test.go
@@ -167,65 +167,3 @@ func TestValidator_Validate_FieldOfTypeAny(t *testing.T) {
 	err = val.Validate(msg)
 	require.NoError(t, err)
 }
-
-func TestValidator_RequiredOneof(t *testing.T) {
-	t.Parallel()
-	val, err := New()
-	require.NoError(t, err)
-
-	tests := []struct {
-		msg   *pb.RequiredOneof
-		exErr bool
-	}{
-		{
-			&pb.RequiredOneof{},
-			true,
-		},
-		{
-			&pb.RequiredOneof{
-				RequiredOneof: &pb.RequiredOneof_Fld_2{
-					// nil FieldMask is empty.
-					Fld_2: nil,
-				},
-			},
-			true,
-		},
-		{
-			&pb.RequiredOneof{
-				RequiredOneof: &pb.RequiredOneof_Fld_2{
-					// this passes `required`
-					Fld_2: &fieldmaskpb.FieldMask{},
-				},
-			},
-			false,
-		},
-		{
-			&pb.RequiredOneof{
-				RequiredOneof: &pb.RequiredOneof_Fld_1{
-					// empty string does not pass `required` as a normal field,
-					// and it shouldn't pass it here either.
-					Fld_1: "",
-				},
-			},
-			true,
-		},
-		{
-			&pb.RequiredOneof{
-				RequiredOneof: &pb.RequiredOneof_Fld_1{
-					// passes `required`
-					Fld_1: "foo",
-				},
-			},
-			false,
-		},
-	}
-	for _, test := range tests {
-		test := test
-		err = val.Validate(test.msg)
-		if test.exErr {
-			require.Error(t, err)
-		} else {
-			require.NoError(t, err)
-		}
-	}
-}