diff --git a/experimental/ir/lower_features.go b/experimental/ir/lower_features.go
index 8fd7aed2..d527bb6a 100644
--- a/experimental/ir/lower_features.go
+++ b/experimental/ir/lower_features.go
@@ -278,25 +278,33 @@ func validateAllFeatures(file *File, r *report.Report) {
 			parent:  parent,
 		}))
 
+		// Oneof features must be resolved before member features, since a field
+		// declared inside a oneof inherits from the oneof.
+		for oneof := range seq.Values(ty.Oneofs()) {
+			features := oneof.Options().Field(builtins.OneofFeatures)
+			validateFeatures(features.AsMessage(), r)
+			oneof.Raw().features = id.ID[FeatureSet](file.arenas.features.NewCompressed(rawFeatureSet{
+				options: features.ID(),
+				parent:  ty.Raw().features,
+			}))
+		}
 		for member := range seq.Values(ty.Members()) {
 			option := builtins.FieldFeatures
 			if member.IsEnumValue() {
 				option = builtins.EnumFeatures
 			}
 
+			// A field belonging to a oneof inherits features from the oneof.
+			parent := ty.Raw().features
+			if oneof := member.Oneof(); !oneof.IsZero() {
+				parent = oneof.Raw().features
+			}
+
 			features := member.Options().Field(option)
 			validateFeatures(features.AsMessage(), r)
 			member.Raw().features = id.ID[FeatureSet](file.arenas.features.NewCompressed(rawFeatureSet{
 				options: features.ID(),
-				parent:  ty.Raw().features,
-			}))
-		}
-		for oneof := range seq.Values(ty.Oneofs()) {
-			features := oneof.Options().Field(builtins.OneofFeatures)
-			validateFeatures(features.AsMessage(), r)
-			oneof.Raw().features = id.ID[FeatureSet](file.arenas.features.NewCompressed(rawFeatureSet{
-				options: features.ID(),
-				parent:  ty.Raw().features,
+				parent:  parent,
 			}))
 		}
 		for extns := range seq.Values(ty.ExtensionRanges()) {
diff --git a/experimental/ir/testdata/editions/naming_style_2024_bad.proto b/experimental/ir/testdata/editions/naming_style_2024_bad.proto
index 5c7962f8..049add12 100644
--- a/experimental/ir/testdata/editions/naming_style_2024_bad.proto
+++ b/experimental/ir/testdata/editions/naming_style_2024_bad.proto
@@ -13,6 +13,7 @@ message my_message {
   string field__name = 6; // Consecutive underscores
   oneof TestChoice {      // PascalCase oneof
     string choice_a = 7;
+    string badChoice = 8; // camelCase field name
   }
 }
 
diff --git a/experimental/ir/testdata/editions/naming_style_2024_bad.proto.fds.yaml b/experimental/ir/testdata/editions/naming_style_2024_bad.proto.fds.yaml
index 42cf1a8a..6f1f96a9 100644
--- a/experimental/ir/testdata/editions/naming_style_2024_bad.proto.fds.yaml
+++ b/experimental/ir/testdata/editions/naming_style_2024_bad.proto.fds.yaml
@@ -40,6 +40,12 @@ file:
       type: TYPE_STRING
       oneof_index: 0
       json_name: "choiceA"
+    - name: "badChoice"
+      number: 8
+      label: LABEL_OPTIONAL
+      type: TYPE_STRING
+      oneof_index: 0
+      json_name: "badChoice"
     oneof_decl: [{ name: "TestChoice" }]
   - name: "LegacyStyleMessage"
     field:
diff --git a/experimental/ir/testdata/editions/naming_style_2024_bad.proto.stderr.txt b/experimental/ir/testdata/editions/naming_style_2024_bad.proto.stderr.txt
index 11db7faa..1baa5286 100644
--- a/experimental/ir/testdata/editions/naming_style_2024_bad.proto.stderr.txt
+++ b/experimental/ir/testdata/editions/naming_style_2024_bad.proto.stderr.txt
@@ -71,106 +71,114 @@ error: oneof name should be snake_case
    |
    = help: STYLE2024 requires oneof names to be snake_case (e.g., my_choice)
 
+error: field name should be snake_case
+  --> testdata/editions/naming_style_2024_bad.proto:16:12
+   |
+16 |     string badChoice = 8; // camelCase field name
+   |            ^^^^^^^^^ this name violates STYLE2024
+   |
+   = help: STYLE2024 requires field names to be snake_case (e.g., my_field)
+
 error: enum type name should be PascalCase
-  --> testdata/editions/naming_style_2024_bad.proto:19:6
+  --> testdata/editions/naming_style_2024_bad.proto:20:6
    |
-19 | enum my_enum {
+20 | enum my_enum {
    |      ^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires enum names to be PascalCase (e.g., MyEnum)
 
 error: enum value name should be SCREAMING_SNAKE_CASE
-  --> testdata/editions/naming_style_2024_bad.proto:20:3
+  --> testdata/editions/naming_style_2024_bad.proto:21:3
    |
-20 |   unspecified = 0; // lowercase enum value
+21 |   unspecified = 0; // lowercase enum value
    |   ^^^^^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires enum value names to be SCREAMING_SNAKE_CASE (e.g.,
            MY_VALUE)
 
 error: enum value name should be SCREAMING_SNAKE_CASE
-  --> testdata/editions/naming_style_2024_bad.proto:21:3
+  --> testdata/editions/naming_style_2024_bad.proto:22:3
    |
-21 |   valueOne = 1;    // camelCase enum value
+22 |   valueOne = 1;    // camelCase enum value
    |   ^^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires enum value names to be SCREAMING_SNAKE_CASE (e.g.,
            MY_VALUE)
 
 error: enum value name should be SCREAMING_SNAKE_CASE
-  --> testdata/editions/naming_style_2024_bad.proto:22:3
+  --> testdata/editions/naming_style_2024_bad.proto:23:3
    |
-22 |   _VALUE = 2;      // Leading underscore
+23 |   _VALUE = 2;      // Leading underscore
    |   ^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires enum value names to be SCREAMING_SNAKE_CASE (e.g.,
            MY_VALUE)
 
 error: enum value name should be SCREAMING_SNAKE_CASE
-  --> testdata/editions/naming_style_2024_bad.proto:23:3
+  --> testdata/editions/naming_style_2024_bad.proto:24:3
    |
-23 |   VALUE_ = 3;      // Trailing underscore
+24 |   VALUE_ = 3;      // Trailing underscore
    |   ^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires enum value names to be SCREAMING_SNAKE_CASE (e.g.,
            MY_VALUE)
 
 error: enum values have the same name with the `my_enum` prefix removed
-  --> testdata/editions/naming_style_2024_bad.proto:23:3
+  --> testdata/editions/naming_style_2024_bad.proto:24:3
    |
-22 |   _VALUE = 2;      // Leading underscore
+23 |   _VALUE = 2;      // Leading underscore
    |   ------ this implies canonical name `Value`
-23 |   VALUE_ = 3;      // Trailing underscore
+24 |   VALUE_ = 3;      // Trailing underscore
    |   ^^^^^^ this also implies that name
 
 error: enum value name should be SCREAMING_SNAKE_CASE
-  --> testdata/editions/naming_style_2024_bad.proto:24:3
+  --> testdata/editions/naming_style_2024_bad.proto:25:3
    |
-24 |   VALUE_1 = 4;     // Underscore followed by number
+25 |   VALUE_1 = 4;     // Underscore followed by number
    |   ^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires enum value names to be SCREAMING_SNAKE_CASE (e.g.,
            MY_VALUE)
 
 error: service name should be PascalCase
-  --> testdata/editions/naming_style_2024_bad.proto:27:9
+  --> testdata/editions/naming_style_2024_bad.proto:28:9
    |
-27 | service My_Service { // Snake_Case service name
+28 | service My_Service { // Snake_Case service name
    |         ^^^^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires service names to be PascalCase (e.g., MyService)
 
 error: RPC method name should be PascalCase
-  --> testdata/editions/naming_style_2024_bad.proto:28:7
+  --> testdata/editions/naming_style_2024_bad.proto:29:7
    |
-28 |   rpc test_method(my_message) returns (my_message); // snake_case RPC method names
+29 |   rpc test_method(my_message) returns (my_message); // snake_case RPC method names
    |       ^^^^^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires RPC method names to be PascalCase (e.g.,
            GetMessage)
 
 error: field name should be snake_case
-  --> testdata/editions/naming_style_2024_bad.proto:36:10
+  --> testdata/editions/naming_style_2024_bad.proto:37:10
    |
-36 |   string BadField = 2 [features.enforce_naming_style = STYLE2024];
+37 |   string BadField = 2 [features.enforce_naming_style = STYLE2024];
    |          ^^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires field names to be snake_case (e.g., my_field)
 
 error: message type name should be PascalCase
-  --> testdata/editions/naming_style_2024_bad.proto:37:11
+  --> testdata/editions/naming_style_2024_bad.proto:38:11
    |
-37 |   message bad_nested {
+38 |   message bad_nested {
    |           ^^^^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires message names to be PascalCase (e.g., MyMessage)
 
 error: field name should be snake_case
-  --> testdata/editions/naming_style_2024_bad.proto:40:12
+  --> testdata/editions/naming_style_2024_bad.proto:41:12
    |
-40 |     string _bad_field = 1;
+41 |     string _bad_field = 1;
    |            ^^^^^^^^^^ this name violates STYLE2024
    |
    = help: STYLE2024 requires field names to be snake_case (e.g., my_field)
 
-encountered 21 errors
+encountered 22 errors
diff --git a/experimental/ir/testdata/editions/naming_style_2024_bad.proto.symtab.yaml b/experimental/ir/testdata/editions/naming_style_2024_bad.proto.symtab.yaml
index 6e92658d..5b30cbf1 100644
--- a/experimental/ir/testdata/editions/naming_style_2024_bad.proto.symtab.yaml
+++ b/experimental/ir/testdata/editions/naming_style_2024_bad.proto.symtab.yaml
@@ -66,54 +66,59 @@ tables:
       file: "testdata/editions/naming_style_2024_bad.proto"
       index: 7
       visible: true
+    - fqn: "Buf.Test.my_message.badChoice"
+      kind: KIND_FIELD
+      file: "testdata/editions/naming_style_2024_bad.proto"
+      index: 8
+      visible: true
     - fqn: "Buf.Test.LegacyStyleMessage._allowed"
       kind: KIND_FIELD
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 13
+      index: 14
       visible: true
     - fqn: "Buf.Test.LegacyStyleMessage.BadField"
       kind: KIND_FIELD
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 14
+      index: 15
       visible: true
       options.message.fields:
         "features": { message.fields: { "enforce_naming_style": { i32: 1 } } }
     - fqn: "Buf.Test.LegacyStyleMessage.bad_nested._bad_field"
       kind: KIND_FIELD
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 15
+      index: 16
       visible: true
     - fqn: "Buf.Test.LegacyStyleMessage.bad_nested._another_field"
       kind: KIND_FIELD
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 16
+      index: 17
       visible: true
       options.message.fields:
         "features": { message.fields: { "enforce_naming_style": { i32: 2 } } }
     - fqn: "Buf.Test.unspecified"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 8
+      index: 9
       visible: true
     - fqn: "Buf.Test.valueOne"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 9
+      index: 10
       visible: true
     - fqn: "Buf.Test._VALUE"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 10
+      index: 11
       visible: true
     - fqn: "Buf.Test.VALUE_"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 11
+      index: 12
       visible: true
     - fqn: "Buf.Test.VALUE_1"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_bad.proto"
-      index: 12
+      index: 13
       visible: true
     - fqn: "Buf.Test.my_message.TestChoice"
       kind: KIND_ONEOF
diff --git a/experimental/ir/testdata/editions/naming_style_2024_ok.proto b/experimental/ir/testdata/editions/naming_style_2024_ok.proto
index 89fb81be..640b385c 100644
--- a/experimental/ir/testdata/editions/naming_style_2024_ok.proto
+++ b/experimental/ir/testdata/editions/naming_style_2024_ok.proto
@@ -41,6 +41,8 @@ message bad_message_but_ok {
 
   oneof BadChoice {
     string opt_a = 4;
+    int32 BadName = 5;    // PascalCase, allowed inherited STYLE_LEGACY.
+    int32 anotherBad = 6; // camelCase, allowed inherited STYLE_LEGACY.
   }
 
   // Nested message inherits STYLE_LEGACY from parent
@@ -51,6 +53,13 @@ message bad_message_but_ok {
   message GoodNested {
     option features.enforce_naming_style = STYLE2024;
     string good_field = 1; // Must follow STYLE2024 rules
+
+    oneof BadChoice {
+      option features.enforce_naming_style = STYLE_LEGACY;
+
+      int32 oneof_e_1 = 2; // Underscore-before-digit, allowed under STYLE_LEGACY.
+      int32 oneofE2 = 3;   // camelCase, allowed under STYLE_LEGACY.
+    }
   }
 }
 
diff --git a/experimental/ir/testdata/editions/naming_style_2024_ok.proto.fds.yaml b/experimental/ir/testdata/editions/naming_style_2024_ok.proto.fds.yaml
index 2b7ac5e8..7a5fef89 100644
--- a/experimental/ir/testdata/editions/naming_style_2024_ok.proto.fds.yaml
+++ b/experimental/ir/testdata/editions/naming_style_2024_ok.proto.fds.yaml
@@ -60,6 +60,18 @@ file:
       type: TYPE_STRING
       oneof_index: 0
       json_name: "optA"
+    - name: "BadName"
+      number: 5
+      label: LABEL_OPTIONAL
+      type: TYPE_INT32
+      oneof_index: 0
+      json_name: "BadName"
+    - name: "anotherBad"
+      number: 6
+      label: LABEL_OPTIONAL
+      type: TYPE_INT32
+      oneof_index: 0
+      json_name: "anotherBad"
     nested_type:
     - name: "nested_message"
       field:
@@ -75,6 +87,21 @@ file:
         label: LABEL_OPTIONAL
         type: TYPE_STRING
         json_name: "goodField"
+      - name: "oneof_e_1"
+        number: 2
+        label: LABEL_OPTIONAL
+        type: TYPE_INT32
+        oneof_index: 0
+        json_name: "oneofE1"
+      - name: "oneofE2"
+        number: 3
+        label: LABEL_OPTIONAL
+        type: TYPE_INT32
+        oneof_index: 0
+        json_name: "oneofE2"
+      oneof_decl:
+      - name: "BadChoice"
+        options.features.enforce_naming_style: STYLE_LEGACY
       options.features.enforce_naming_style: STYLE2024
     oneof_decl: [{ name: "BadChoice" }]
     options.features.enforce_naming_style: STYLE_LEGACY
diff --git a/experimental/ir/testdata/editions/naming_style_2024_ok.proto.symtab.yaml b/experimental/ir/testdata/editions/naming_style_2024_ok.proto.symtab.yaml
index 61f2aa76..88c03104 100644
--- a/experimental/ir/testdata/editions/naming_style_2024_ok.proto.symtab.yaml
+++ b/experimental/ir/testdata/editions/naming_style_2024_ok.proto.symtab.yaml
@@ -93,16 +93,36 @@ tables:
       file: "testdata/editions/naming_style_2024_ok.proto"
       index: 14
       visible: true
-    - fqn: "buf.test.bad_message_but_ok.nested_message.AnyName"
+    - fqn: "buf.test.bad_message_but_ok.BadName"
       kind: KIND_FIELD
       file: "testdata/editions/naming_style_2024_ok.proto"
       index: 15
       visible: true
-    - fqn: "buf.test.bad_message_but_ok.GoodNested.good_field"
+    - fqn: "buf.test.bad_message_but_ok.anotherBad"
       kind: KIND_FIELD
       file: "testdata/editions/naming_style_2024_ok.proto"
       index: 16
       visible: true
+    - fqn: "buf.test.bad_message_but_ok.nested_message.AnyName"
+      kind: KIND_FIELD
+      file: "testdata/editions/naming_style_2024_ok.proto"
+      index: 17
+      visible: true
+    - fqn: "buf.test.bad_message_but_ok.GoodNested.good_field"
+      kind: KIND_FIELD
+      file: "testdata/editions/naming_style_2024_ok.proto"
+      index: 18
+      visible: true
+    - fqn: "buf.test.bad_message_but_ok.GoodNested.oneof_e_1"
+      kind: KIND_FIELD
+      file: "testdata/editions/naming_style_2024_ok.proto"
+      index: 19
+      visible: true
+    - fqn: "buf.test.bad_message_but_ok.GoodNested.oneofE2"
+      kind: KIND_FIELD
+      file: "testdata/editions/naming_style_2024_ok.proto"
+      index: 20
+      visible: true
     - fqn: "buf.test.MY_ENUM_UNSPECIFIED"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_ok.proto"
@@ -126,17 +146,17 @@ tables:
     - fqn: "buf.test.unspecified"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_ok.proto"
-      index: 17
+      index: 21
       visible: true
     - fqn: "buf.test.valueOne"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_ok.proto"
-      index: 18
+      index: 22
       visible: true
     - fqn: "buf.test._VALUE"
       kind: KIND_ENUM_VALUE
       file: "testdata/editions/naming_style_2024_ok.proto"
-      index: 19
+      index: 23
       visible: true
     - fqn: "buf.test.MyMessage.my_choice"
       kind: KIND_ONEOF
@@ -148,6 +168,13 @@ tables:
       file: "testdata/editions/naming_style_2024_ok.proto"
       index: 2
       visible: true
+    - fqn: "buf.test.bad_message_but_ok.GoodNested.BadChoice"
+      kind: KIND_ONEOF
+      file: "testdata/editions/naming_style_2024_ok.proto"
+      index: 3
+      visible: true
+      options.message.fields:
+        "features": { message.fields: { "enforce_naming_style": { i32: 2 } } }
     - fqn: "buf.test.MyService"
       kind: 9
       file: "testdata/editions/naming_style_2024_ok.proto"