diff --git a/Cargo.lock b/Cargo.lock
index 029fba529c85a..51f328bea6faf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -11995,6 +11995,7 @@ dependencies = [
  "itertools 0.13.0",
  "move-binary-format",
  "move-core-types",
+ "parking_lot 0.12.1",
  "proptest",
  "rand 0.7.3",
  "serde",
diff --git a/aptos-move/aptos-vm/src/verifier/transaction_arg_validation.rs b/aptos-move/aptos-vm/src/verifier/transaction_arg_validation.rs
index d6a96952a88e7..97ed268e84641 100644
--- a/aptos-move/aptos-vm/src/verifier/transaction_arg_validation.rs
+++ b/aptos-move/aptos-vm/src/verifier/transaction_arg_validation.rs
@@ -190,7 +190,10 @@ pub(crate) fn validate_combine_signer_and_txn_args(
     Ok(combined_args)
 }
 
-// Return whether the argument is valid/allowed and whether it needs construction.
+/// Returns true if the argument is valid (that is, it is a primitive type or a struct with a
+/// known constructor function). Otherwise, (for structs without constructors, signers or
+/// references) returns false. An error is returned in cases when a struct type is encountered and
+/// its name cannot be queried for some reason.
 pub(crate) fn is_valid_txn_arg(
     session: &SessionExt,
     module_storage: &impl AptosModuleStorage,
@@ -202,12 +205,21 @@ pub(crate) fn is_valid_txn_arg(
     match ty {
         Bool | U8 | U16 | U32 | U64 | U128 | U256 | Address => true,
         Vector(inner) => is_valid_txn_arg(session, module_storage, inner, allowed_structs),
-        Struct { idx, .. } | StructInstantiation { idx, .. } => session
-            .fetch_struct_ty_by_idx(*idx, module_storage)
-            .is_some_and(|st| {
-                let full_name = format!("{}::{}", st.module.short_str_lossless(), st.name);
-                allowed_structs.contains_key(&full_name)
-            }),
+        Struct { .. } | StructInstantiation { .. } => {
+            // Note: Original behavior was to return false even if the module loading fails (e.g.,
+            //       if struct does not exist. This preserves it.
+            session
+                .get_struct_name(ty, module_storage)
+                .ok()
+                .flatten()
+                .is_some_and(|(module_id, identifier)| {
+                    allowed_structs.contains_key(&format!(
+                        "{}::{}",
+                        module_id.short_str_lossless(),
+                        identifier
+                    ))
+                })
+        },
         Signer | Reference(_) | MutableReference(_) | TyParam(_) => false,
     }
 }
@@ -340,12 +352,16 @@ pub(crate) fn recursively_construct_arg(
                 len -= 1;
             }
         },
-        Struct { idx, .. } | StructInstantiation { idx, .. } => {
-            let st = session
-                .fetch_struct_ty_by_idx(*idx, module_storage)
+        Struct { .. } | StructInstantiation { .. } => {
+            let (module_id, identifier) = session
+                .get_struct_name(ty, module_storage)
+                .map_err(|_| {
+                    // Note: The original behaviour was to map all errors to an invalid signature
+                    //       error, here we want to preserve it for now.
+                    invalid_signature()
+                })?
                 .ok_or_else(invalid_signature)?;
-
-            let full_name = format!("{}::{}", st.module.short_str_lossless(), st.name);
+            let full_name = format!("{}::{}", module_id.short_str_lossless(), identifier);
             let constructor = allowed_structs
                 .get(&full_name)
                 .ok_or_else(invalid_signature)?;
diff --git a/third_party/move/move-vm/integration-tests/Cargo.toml b/third_party/move/move-vm/integration-tests/Cargo.toml
index 9a592c082f8e3..e88fc6987a0c0 100644
--- a/third_party/move/move-vm/integration-tests/Cargo.toml
+++ b/third_party/move/move-vm/integration-tests/Cargo.toml
@@ -21,7 +21,7 @@ move-core-types = { workspace = true }
 move-stdlib = { path = "../../move-stdlib" }
 move-vm-runtime = { workspace = true, features = ["testing"] }
 move-vm-test-utils = { workspace = true }
-move-vm-types = { workspace = true }
+move-vm-types = { workspace = true, features = ["testing"] }
 smallvec = { workspace = true }
 tempfile = { workspace = true }
 
diff --git a/third_party/move/move-vm/integration-tests/src/tests/module_storage_tests.rs b/third_party/move/move-vm/integration-tests/src/tests/module_storage_tests.rs
index 7e17e4bb44af9..6b7471e835b5f 100644
--- a/third_party/move/move-vm/integration-tests/src/tests/module_storage_tests.rs
+++ b/third_party/move/move-vm/integration-tests/src/tests/module_storage_tests.rs
@@ -15,7 +15,10 @@ use move_vm_runtime::{
 };
 use move_vm_test_utils::InMemoryStorage;
 use move_vm_types::{
-    loaded_data::runtime_types::{AbilityInfo, StructIdentifier, StructNameIndex, TypeBuilder},
+    loaded_data::{
+        runtime_types::{AbilityInfo, StructIdentifier, TypeBuilder},
+        struct_name_indexing::StructNameIndex,
+    },
     value_serde::FunctionValueExtension,
 };
 use std::str::FromStr;
@@ -74,7 +77,7 @@ fn test_function_value_extension() {
     let foo_ty = types.pop().unwrap();
     let name = module_storage
         .runtime_environment()
-        .idx_to_struct_name_for_test(StructNameIndex(0))
+        .idx_to_struct_name_for_test(StructNameIndex::new(0))
         .unwrap();
     assert_eq!(name, StructIdentifier {
         module: test_id.clone(),
@@ -84,8 +87,10 @@ fn test_function_value_extension() {
         foo_ty,
         ty_builder
             .create_ref_ty(
-                &ty_builder
-                    .create_struct_ty(StructNameIndex(0), AbilityInfo::struct_(AbilitySet::EMPTY)),
+                &ty_builder.create_struct_ty(
+                    StructNameIndex::new(0),
+                    AbilityInfo::struct_(AbilitySet::EMPTY)
+                ),
                 false
             )
             .unwrap()
@@ -121,7 +126,7 @@ fn test_function_value_extension() {
     let bar_ty = types.pop().unwrap();
     let name = module_storage
         .runtime_environment()
-        .idx_to_struct_name_for_test(StructNameIndex(1))
+        .idx_to_struct_name_for_test(StructNameIndex::new(1))
         .unwrap();
     assert_eq!(name, StructIdentifier {
         module: other_test_id,
@@ -130,7 +135,7 @@ fn test_function_value_extension() {
     assert_eq!(
         bar_ty,
         ty_builder.create_struct_ty(
-            StructNameIndex(1),
+            StructNameIndex::new(1),
             AbilityInfo::struct_(AbilitySet::from_u8(Ability::Drop as u8).unwrap())
         )
     );
diff --git a/third_party/move/move-vm/runtime/src/loader/mod.rs b/third_party/move/move-vm/runtime/src/loader/mod.rs
index 2753b3775b850..fe5ec818db599 100644
--- a/third_party/move/move-vm/runtime/src/loader/mod.rs
+++ b/third_party/move/move-vm/runtime/src/loader/mod.rs
@@ -28,10 +28,15 @@ use move_core_types::{
     value::MoveTypeLayout,
     vm_status::StatusCode,
 };
+use move_vm_metrics::{Timer, VM_TIMER};
 use move_vm_types::{
     gas::GasMeter,
-    loaded_data::runtime_types::{AbilityInfo, StructNameIndex, StructType, Type},
+    loaded_data::{
+        runtime_types::{AbilityInfo, StructType, Type},
+        struct_name_indexing::StructNameIndex,
+    },
     sha3_256,
+    value_serde::FunctionValueExtension,
 };
 use parking_lot::{Mutex, RwLock};
 use std::{
@@ -39,6 +44,7 @@ use std::{
     hash::Hash,
     sync::Arc,
 };
+use type_loader::intern_type;
 use typed_arena::Arena;
 
 mod access_specifier_loader;
@@ -51,8 +57,7 @@ use crate::{
     loader::modules::{StructVariantInfo, VariantFieldInfo},
     native_functions::NativeFunctions,
     storage::{
-        loader::LoaderV2, module_storage::FunctionValueExtensionAdapter,
-        struct_name_index_map::StructNameIndexMap, ty_cache::StructInfoCache,
+        loader::LoaderV2, module_storage::FunctionValueExtensionAdapter, ty_cache::StructInfoCache,
         ty_layout_converter::LoaderLayoutConverter, ty_tag_converter::TypeTagConverter,
     },
 };
@@ -64,14 +69,12 @@ use move_binary_format::file_format::{
     StructVariantHandleIndex, StructVariantInstantiationIndex, TypeParameterIndex,
     VariantFieldHandleIndex, VariantFieldInstantiationIndex, VariantIndex,
 };
-use move_vm_metrics::{Timer, VM_TIMER};
-use move_vm_types::{
-    loaded_data::runtime_types::{DepthFormula, StructLayout, TypeBuilder},
-    value_serde::FunctionValueExtension,
+use move_vm_types::loaded_data::{
+    runtime_types::{DepthFormula, StructLayout, TypeBuilder},
+    struct_name_indexing::StructNameIndexMap,
 };
 pub use script::Script;
 pub(crate) use script::ScriptCache;
-use type_loader::intern_type;
 
 type ScriptHash = [u8; 32];
 
diff --git a/third_party/move/move-vm/runtime/src/loader/modules.rs b/third_party/move/move-vm/runtime/src/loader/modules.rs
index 388363f1ded0e..db0f27e24a5f3 100644
--- a/third_party/move/move-vm/runtime/src/loader/modules.rs
+++ b/third_party/move/move-vm/runtime/src/loader/modules.rs
@@ -9,7 +9,6 @@ use crate::{
         BinaryCache,
     },
     native_functions::NativeFunctions,
-    storage::struct_name_index_map::StructNameIndexMap,
 };
 use move_binary_format::{
     access::ModuleAccess,
@@ -29,8 +28,9 @@ use move_core_types::{
     vm_status::StatusCode,
 };
 use move_vm_metrics::{Timer, VM_TIMER};
-use move_vm_types::loaded_data::runtime_types::{
-    StructIdentifier, StructLayout, StructNameIndex, StructType, Type,
+use move_vm_types::loaded_data::{
+    runtime_types::{StructIdentifier, StructLayout, StructType, Type},
+    struct_name_indexing::{StructNameIndex, StructNameIndexMap},
 };
 use parking_lot::RwLock;
 use std::{
@@ -575,7 +575,6 @@ impl Module {
     ) -> PartialVMResult<StructType> {
         let struct_handle = module.struct_handle_at(struct_def.struct_handle);
         let abilities = struct_handle.abilities;
-        let name = module.identifier_at(struct_handle.name).to_owned();
         let ty_params = struct_handle.type_parameters.clone();
         let layout = match &struct_def.field_information {
             StructFieldInformation::Native => unreachable!("native structs have been removed"),
@@ -613,8 +612,6 @@ impl Module {
             abilities,
             ty_params,
             idx: struct_name_table[struct_def.struct_handle.0 as usize],
-            module: module.self_id(),
-            name,
         })
     }
 
diff --git a/third_party/move/move-vm/runtime/src/loader/script.rs b/third_party/move/move-vm/runtime/src/loader/script.rs
index cddfdea0f3548..7c3b9beac6c54 100644
--- a/third_party/move/move-vm/runtime/src/loader/script.rs
+++ b/third_party/move/move-vm/runtime/src/loader/script.rs
@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 
 use super::{intern_type, BinaryCache, Function, FunctionHandle, FunctionInstantiation};
-use crate::{loader::ScriptHash, storage::struct_name_index_map::StructNameIndexMap};
+use crate::loader::ScriptHash;
 use move_binary_format::{
     access::ScriptAccess,
     binary_views::BinaryIndexedView,
@@ -13,6 +13,7 @@ use move_core_types::{identifier::Identifier, language_storage::ModuleId, vm_sta
 use move_vm_types::loaded_data::{
     runtime_access_specifier::AccessSpecifier,
     runtime_types::{StructIdentifier, Type},
+    struct_name_indexing::StructNameIndexMap,
 };
 use std::{collections::BTreeMap, ops::Deref, sync::Arc};
 
diff --git a/third_party/move/move-vm/runtime/src/loader/type_loader.rs b/third_party/move/move-vm/runtime/src/loader/type_loader.rs
index c37a7513e4856..dbea652d3c703 100644
--- a/third_party/move/move-vm/runtime/src/loader/type_loader.rs
+++ b/third_party/move/move-vm/runtime/src/loader/type_loader.rs
@@ -7,7 +7,10 @@ use move_binary_format::{
     file_format::SignatureToken,
 };
 use move_core_types::vm_status::StatusCode;
-use move_vm_types::loaded_data::runtime_types::{AbilityInfo, StructNameIndex, Type};
+use move_vm_types::loaded_data::{
+    runtime_types::{AbilityInfo, Type},
+    struct_name_indexing::StructNameIndex,
+};
 use triomphe::Arc as TriompheArc;
 
 /// Converts a signature token into the in memory type representation used by the MoveVM.
diff --git a/third_party/move/move-vm/runtime/src/session.rs b/third_party/move/move-vm/runtime/src/session.rs
index 7799a95b2953c..831c1e93e696d 100644
--- a/third_party/move/move-vm/runtime/src/session.rs
+++ b/third_party/move/move-vm/runtime/src/session.rs
@@ -18,17 +18,17 @@ use move_core_types::{
     account_address::AccountAddress,
     effects::{ChangeSet, Changes},
     gas_algebra::NumBytes,
-    identifier::IdentStr,
+    identifier::{IdentStr, Identifier},
     language_storage::{ModuleId, TypeTag},
     value::MoveTypeLayout,
     vm_status::StatusCode,
 };
 use move_vm_types::{
     gas::GasMeter,
-    loaded_data::runtime_types::{StructNameIndex, StructType, Type, TypeBuilder},
+    loaded_data::runtime_types::{Type, TypeBuilder},
     values::{GlobalValue, Value},
 };
-use std::{borrow::Borrow, collections::BTreeSet, sync::Arc};
+use std::{borrow::Borrow, collections::BTreeSet};
 
 pub struct Session<'r, 'l> {
     pub(crate) move_vm: &'l MoveVM,
@@ -527,16 +527,28 @@ impl<'r, 'l> Session<'r, 'l> {
         self.move_vm.runtime.loader().ty_builder()
     }
 
-    pub fn fetch_struct_ty_by_idx(
+    /// If type is a (generic or non-generic) struct or enum, returns its name. Otherwise, returns
+    /// [None].
+    pub fn get_struct_name(
         &self,
-        idx: StructNameIndex,
-        module_storage: &impl ModuleStorage,
-    ) -> Option<Arc<StructType>> {
-        self.move_vm
-            .runtime
-            .loader()
-            .fetch_struct_ty_by_idx(idx, &self.module_store, module_storage)
-            .ok()
+        ty: &Type,
+        module_storage: &dyn ModuleStorage,
+    ) -> PartialVMResult<Option<(ModuleId, Identifier)>> {
+        use Type::*;
+
+        Ok(match ty {
+            Struct { idx, .. } | StructInstantiation { idx, .. } => {
+                let struct_identifier = self
+                    .move_vm
+                    .runtime
+                    .loader()
+                    .struct_name_index_map(module_storage)
+                    .idx_to_struct_name(*idx)?;
+                Some((struct_identifier.module, struct_identifier.name))
+            },
+            Bool | U8 | U16 | U32 | U64 | U128 | U256 | Address | Signer | TyParam(_)
+            | Vector(_) | Reference(_) | MutableReference(_) => None,
+        })
     }
 
     pub fn check_type_tag_dependencies_and_charge_gas(
diff --git a/third_party/move/move-vm/runtime/src/storage/environment.rs b/third_party/move/move-vm/runtime/src/storage/environment.rs
index 678c7ad35f935..057b1be157fb9 100644
--- a/third_party/move/move-vm/runtime/src/storage/environment.rs
+++ b/third_party/move/move-vm/runtime/src/storage/environment.rs
@@ -6,8 +6,8 @@ use crate::{
     loader::check_natives,
     native_functions::{NativeFunction, NativeFunctions},
     storage::{
-        struct_name_index_map::StructNameIndexMap, ty_cache::StructInfoCache,
-        ty_tag_converter::TypeTagCache, verified_module_cache::VERIFIED_MODULES_V2,
+        ty_cache::StructInfoCache, ty_tag_converter::TypeTagCache,
+        verified_module_cache::VERIFIED_MODULES_V2,
     },
     Module, Script,
 };
@@ -26,8 +26,11 @@ use move_core_types::{
     vm_status::{sub_status::unknown_invariant_violation::EPARANOID_FAILURE, StatusCode},
 };
 use move_vm_metrics::{Timer, VM_TIMER};
+use move_vm_types::loaded_data::struct_name_indexing::StructNameIndexMap;
 #[cfg(any(test, feature = "testing"))]
-use move_vm_types::loaded_data::runtime_types::{StructIdentifier, StructNameIndex};
+use move_vm_types::loaded_data::{
+    runtime_types::StructIdentifier, struct_name_indexing::StructNameIndex,
+};
 use std::sync::Arc;
 
 /// [MoveVM] runtime environment encapsulating different configurations. Shared between the VM and
diff --git a/third_party/move/move-vm/runtime/src/storage/mod.rs b/third_party/move/move-vm/runtime/src/storage/mod.rs
index 134f241346d94..72e42aa2f7ff4 100644
--- a/third_party/move/move-vm/runtime/src/storage/mod.rs
+++ b/third_party/move/move-vm/runtime/src/storage/mod.rs
@@ -2,7 +2,6 @@
 // SPDX-License-Identifier: Apache-2.0
 
 pub(crate) mod loader;
-pub(crate) mod struct_name_index_map;
 pub(crate) mod ty_cache;
 pub(crate) mod ty_tag_converter;
 mod verified_module_cache;
diff --git a/third_party/move/move-vm/runtime/src/storage/ty_cache.rs b/third_party/move/move-vm/runtime/src/storage/ty_cache.rs
index 8ca1aae3361c4..53091a720cef9 100644
--- a/third_party/move/move-vm/runtime/src/storage/ty_cache.rs
+++ b/third_party/move/move-vm/runtime/src/storage/ty_cache.rs
@@ -1,10 +1,12 @@
 // Copyright (c) The Move Contributors
 // SPDX-License-Identifier: Apache-2.0
 
-use crate::storage::struct_name_index_map::StructNameIndexMap;
 use move_binary_format::errors::{PartialVMError, PartialVMResult};
 use move_core_types::{language_storage::StructTag, value::MoveTypeLayout, vm_status::StatusCode};
-use move_vm_types::loaded_data::runtime_types::{DepthFormula, StructNameIndex, Type};
+use move_vm_types::loaded_data::{
+    runtime_types::{DepthFormula, Type},
+    struct_name_indexing::{StructNameIndex, StructNameIndexMap},
+};
 use parking_lot::RwLock;
 
 /// Layout information of a single struct instantiation.
diff --git a/third_party/move/move-vm/runtime/src/storage/ty_layout_converter.rs b/third_party/move/move-vm/runtime/src/storage/ty_layout_converter.rs
index 22bdb610c005b..b65abc96e70ab 100644
--- a/third_party/move/move-vm/runtime/src/storage/ty_layout_converter.rs
+++ b/third_party/move/move-vm/runtime/src/storage/ty_layout_converter.rs
@@ -4,10 +4,7 @@
 use crate::{
     config::VMConfig,
     loader::{LegacyModuleStorageAdapter, Loader, PseudoGasContext, VALUE_DEPTH_MAX},
-    storage::{
-        struct_name_index_map::StructNameIndexMap, ty_cache::StructInfoCache,
-        ty_tag_converter::TypeTagConverter,
-    },
+    storage::{ty_cache::StructInfoCache, ty_tag_converter::TypeTagConverter},
     ModuleStorage,
 };
 use move_binary_format::errors::{PartialVMError, PartialVMResult};
@@ -16,7 +13,10 @@ use move_core_types::{
     value::{IdentifierMappingKind, MoveFieldLayout, MoveStructLayout, MoveTypeLayout},
     vm_status::StatusCode,
 };
-use move_vm_types::loaded_data::runtime_types::{StructLayout, StructNameIndex, StructType, Type};
+use move_vm_types::loaded_data::{
+    runtime_types::{StructLayout, StructType, Type},
+    struct_name_indexing::{StructNameIndex, StructNameIndexMap},
+};
 use std::sync::Arc;
 
 /// Maximal nodes which are allowed when converting to layout. This includes the types of
diff --git a/third_party/move/move-vm/runtime/src/storage/ty_tag_converter.rs b/third_party/move/move-vm/runtime/src/storage/ty_tag_converter.rs
index b082ccaa63d19..00d502aec39d3 100644
--- a/third_party/move/move-vm/runtime/src/storage/ty_tag_converter.rs
+++ b/third_party/move/move-vm/runtime/src/storage/ty_tag_converter.rs
@@ -7,7 +7,7 @@ use move_core_types::{
     language_storage::{StructTag, TypeTag},
     vm_status::StatusCode,
 };
-use move_vm_types::loaded_data::runtime_types::{StructNameIndex, Type};
+use move_vm_types::loaded_data::{runtime_types::Type, struct_name_indexing::StructNameIndex};
 use parking_lot::RwLock;
 use std::collections::{hash_map::Entry, HashMap};
 
@@ -239,24 +239,26 @@ mod tests {
     fn test_type_tag_cache() {
         let cache = TypeTagCache::empty();
         assert!(cache.cache.read().is_empty());
-        assert!(cache.get_struct_tag(&StructNameIndex(0), &[]).is_none());
+        assert!(cache
+            .get_struct_tag(&StructNameIndex::new(0), &[])
+            .is_none());
 
         let tag = PricedStructTag {
             struct_tag: StructTag::from_str("0x1::foo::Foo").unwrap(),
             pseudo_gas_cost: 10,
         };
-        assert!(cache.insert_struct_tag(&StructNameIndex(0), &[], &tag));
+        assert!(cache.insert_struct_tag(&StructNameIndex::new(0), &[], &tag));
 
         let tag = PricedStructTag {
             struct_tag: StructTag::from_str("0x1::foo::Foo").unwrap(),
             // Set different cost to check.
             pseudo_gas_cost: 100,
         };
-        assert!(!cache.insert_struct_tag(&StructNameIndex(0), &[], &tag));
+        assert!(!cache.insert_struct_tag(&StructNameIndex::new(0), &[], &tag));
 
         assert_eq!(cache.cache.read().len(), 1);
         let cost = cache
-            .get_struct_tag(&StructNameIndex(0), &[])
+            .get_struct_tag(&StructNameIndex::new(0), &[])
             .unwrap()
             .pseudo_gas_cost;
         assert_eq!(cost, 10);
@@ -344,8 +346,6 @@ mod tests {
                 constraints: AbilitySet::EMPTY,
                 is_phantom: false,
             }],
-            name: Identifier::new("Foo").unwrap(),
-            module: ModuleId::new(AccountAddress::TWO, Identifier::new("foo").unwrap()),
         };
         let generic_struct_ty = ty_builder
             .create_struct_instantiation_ty(&struct_ty, &[Type::TyParam(0)], &[bool_vec_ty])
diff --git a/third_party/move/move-vm/types/Cargo.toml b/third_party/move/move-vm/types/Cargo.toml
index 858a924fc1641..7e70d23dccdae 100644
--- a/third_party/move/move-vm/types/Cargo.toml
+++ b/third_party/move/move-vm/types/Cargo.toml
@@ -20,6 +20,7 @@ hashbrown = { workspace = true }
 itertools = { workspace = true }
 move-binary-format = { workspace = true }
 move-core-types = { workspace = true }
+parking_lot = { workspace = true }
 proptest = { workspace = true, optional = true }
 serde = { workspace = true, features = ["derive", "rc"] }
 sha3 = { workspace = true }
diff --git a/third_party/move/move-vm/types/src/code/errors.rs b/third_party/move/move-vm/types/src/code/errors.rs
index 54bfd5a8e5fa7..1a276e2f939ee 100644
--- a/third_party/move/move-vm/types/src/code/errors.rs
+++ b/third_party/move/move-vm/types/src/code/errors.rs
@@ -1,17 +1,6 @@
 // Copyright (c) The Move Contributors
 // SPDX-License-Identifier: Apache-2.0
 
-#[macro_export]
-macro_rules! panic_error {
-    ($msg:expr) => {{
-        println!("[Error] panic detected: {}", $msg);
-        move_binary_format::errors::PartialVMError::new(
-            move_core_types::vm_status::StatusCode::DELAYED_FIELD_OR_BLOCKSTM_CODE_INVARIANT_ERROR,
-        )
-        .with_message(format!("Panic detected: {:?}", $msg))
-    }};
-}
-
 #[macro_export]
 macro_rules! module_storage_error {
     ($addr:expr, $name:expr, $err:ident) => {
diff --git a/third_party/move/move-vm/types/src/loaded_data/mod.rs b/third_party/move/move-vm/types/src/loaded_data/mod.rs
index 50ceaba95ca0e..d650a543423b9 100644
--- a/third_party/move/move-vm/types/src/loaded_data/mod.rs
+++ b/third_party/move/move-vm/types/src/loaded_data/mod.rs
@@ -9,3 +9,4 @@ pub mod runtime_access_specifier;
 #[cfg(test)]
 mod runtime_access_specifiers_prop_tests;
 pub mod runtime_types;
+pub mod struct_name_indexing;
diff --git a/third_party/move/move-vm/types/src/loaded_data/runtime_types.rs b/third_party/move/move-vm/types/src/loaded_data/runtime_types.rs
index 60a648056d999..76f6dbce6d79f 100644
--- a/third_party/move/move-vm/types/src/loaded_data/runtime_types.rs
+++ b/third_party/move/move-vm/types/src/loaded_data/runtime_types.rs
@@ -4,6 +4,7 @@
 
 #![allow(clippy::non_canonical_partial_ord_impl)]
 
+use crate::loaded_data::struct_name_indexing::StructNameIndex;
 use derivative::Derivative;
 use itertools::Itertools;
 use move_binary_format::{
@@ -12,8 +13,6 @@ use move_binary_format::{
         SignatureToken, StructHandle, StructTypeParameter, TypeParameterIndex, VariantIndex,
     },
 };
-#[cfg(test)]
-use move_core_types::account_address::AccountAddress;
 use move_core_types::{
     ability::{Ability, AbilitySet},
     identifier::Identifier,
@@ -133,8 +132,6 @@ pub struct StructType {
     pub phantom_ty_params_mask: SmallBitVec,
     pub abilities: AbilitySet,
     pub ty_params: Vec<StructTypeParameter>,
-    pub name: Identifier,
-    pub module: ModuleId,
 }
 
 #[derive(Debug, Clone, Eq, Hash, PartialEq)]
@@ -249,20 +246,15 @@ impl StructType {
     #[cfg(test)]
     pub fn for_test() -> StructType {
         Self {
-            idx: StructNameIndex(0),
+            idx: StructNameIndex::new(0),
             layout: StructLayout::Single(vec![]),
             phantom_ty_params_mask: SmallBitVec::new(),
             abilities: AbilitySet::EMPTY,
             ty_params: vec![],
-            name: Identifier::new("Foo").unwrap(),
-            module: ModuleId::new(AccountAddress::ONE, Identifier::new("foo").unwrap()),
         }
     }
 }
 
-#[derive(Debug, Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
-pub struct StructNameIndex(pub usize);
-
 #[derive(Debug, Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct StructIdentifier {
     pub module: ModuleId,
@@ -751,7 +743,7 @@ impl fmt::Display for Type {
             Address => f.write_str("address"),
             Signer => f.write_str("signer"),
             Vector(et) => write!(f, "vector<{}>", et),
-            Struct { idx, ability: _ } => write!(f, "s#{}", idx.0),
+            Struct { idx, ability: _ } => write!(f, "s#{}", idx),
             StructInstantiation {
                 idx,
                 ty_args,
@@ -759,7 +751,7 @@ impl fmt::Display for Type {
             } => write!(
                 f,
                 "s#{}<{}>",
-                idx.0,
+                idx,
                 ty_args.iter().map(|t| t.to_string()).join(",")
             ),
             Reference(t) => write!(f, "&{}", t),
@@ -1221,7 +1213,7 @@ mod unit_tests {
 
     fn struct_instantiation_ty_for_test(ty_args: Vec<Type>) -> Type {
         Type::StructInstantiation {
-            idx: StructNameIndex(0),
+            idx: StructNameIndex::new(0),
             ability: AbilityInfo::struct_(AbilitySet::EMPTY),
             ty_args: TriompheArc::new(ty_args),
         }
@@ -1229,7 +1221,7 @@ mod unit_tests {
 
     fn struct_ty_for_test() -> Type {
         Type::Struct {
-            idx: StructNameIndex(0),
+            idx: StructNameIndex::new(0),
             ability: AbilityInfo::struct_(AbilitySet::EMPTY),
         }
     }
@@ -1372,7 +1364,7 @@ mod unit_tests {
 
     #[test]
     fn test_create_struct_ty() {
-        let idx = StructNameIndex(0);
+        let idx = StructNameIndex::new(0);
         let ability_info = AbilityInfo::struct_(AbilitySet::EMPTY);
 
         // Limits are not relevant here.
diff --git a/third_party/move/move-vm/runtime/src/storage/struct_name_index_map.rs b/third_party/move/move-vm/types/src/loaded_data/struct_name_indexing.rs
similarity index 85%
rename from third_party/move/move-vm/runtime/src/storage/struct_name_index_map.rs
rename to third_party/move/move-vm/types/src/loaded_data/struct_name_indexing.rs
index 98329a6845a73..0da5bf8936a07 100644
--- a/third_party/move/move-vm/runtime/src/storage/struct_name_index_map.rs
+++ b/third_party/move/move-vm/types/src/loaded_data/struct_name_indexing.rs
@@ -1,14 +1,41 @@
 // Copyright (c) The Move Contributors
 // SPDX-License-Identifier: Apache-2.0
 
+use crate::loaded_data::runtime_types::StructIdentifier;
 use move_binary_format::errors::PartialVMResult;
 use move_core_types::language_storage::{StructTag, TypeTag};
-use move_vm_types::{
-    loaded_data::runtime_types::{StructIdentifier, StructNameIndex},
-    panic_error,
-};
 use parking_lot::RwLock;
-use std::{collections::BTreeMap, sync::Arc};
+use std::{collections::BTreeMap, fmt::Formatter, sync::Arc};
+
+macro_rules! panic_error {
+    ($msg:expr) => {{
+        println!("[Error] panic detected: {}", $msg);
+        move_binary_format::errors::PartialVMError::new(
+            move_core_types::vm_status::StatusCode::DELAYED_FIELD_OR_BLOCKSTM_CODE_INVARIANT_ERROR,
+        )
+        .with_message(format!("Panic detected: {:?}", $msg))
+    }};
+}
+
+/// Represents a unique identifier for the struct name. Note that this index has no public
+/// constructor - the only way to construct it is via [StructNameIndexMap].
+#[derive(Debug, Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub struct StructNameIndex(usize);
+
+impl StructNameIndex {
+    /// Creates a new index for testing purposes only. For production, indices must always be
+    /// created by the data structure that uses them to intern struct names.
+    #[cfg(any(test, feature = "testing"))]
+    pub fn new(idx: usize) -> Self {
+        Self(idx)
+    }
+}
+
+impl std::fmt::Display for StructNameIndex {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
 
 #[derive(Clone)]
 struct IndexMap<T: Clone + Ord> {
@@ -19,11 +46,11 @@ struct IndexMap<T: Clone + Ord> {
 /// A data structure to cache struct identifiers (address, module name, struct name) and use
 /// indices instead, to save on the memory consumption and avoid unnecessary cloning. It
 /// guarantees that the same struct name identifier always corresponds to a unique index.
-pub(crate) struct StructNameIndexMap(RwLock<IndexMap<StructIdentifier>>);
+pub struct StructNameIndexMap(RwLock<IndexMap<StructIdentifier>>);
 
 impl StructNameIndexMap {
     /// Returns an empty map with no entries.
-    pub(crate) fn empty() -> Self {
+    pub fn empty() -> Self {
         Self(RwLock::new(IndexMap {
             forward_map: BTreeMap::new(),
             backward_map: vec![],
@@ -31,7 +58,7 @@ impl StructNameIndexMap {
     }
 
     /// Flushes the cached struct names and indices.
-    pub(crate) fn flush(&self) {
+    pub fn flush(&self) {
         let mut index_map = self.0.write();
         index_map.backward_map.clear();
         index_map.forward_map.clear();
@@ -40,7 +67,7 @@ impl StructNameIndexMap {
     /// Maps the struct identifier into an index. If the identifier already exists returns the
     /// corresponding index. This function guarantees that for any struct identifiers A and B,
     /// if A == B, they have the same indices.
-    pub(crate) fn struct_name_to_idx(
+    pub fn struct_name_to_idx(
         &self,
         struct_name: &StructIdentifier,
     ) -> PartialVMResult<StructNameIndex> {
@@ -88,7 +115,7 @@ impl StructNameIndexMap {
 
     /// Returns the reference of the struct name corresponding to the index. Here, we wrap the
     /// name into an [Arc] to ensure that the lock is released.
-    pub(crate) fn idx_to_struct_name_ref(
+    pub fn idx_to_struct_name_ref(
         &self,
         idx: StructNameIndex,
     ) -> PartialVMResult<Arc<StructIdentifier>> {
@@ -98,10 +125,7 @@ impl StructNameIndexMap {
 
     /// Returns the clone of the struct name corresponding to the index. The clone ensures that the
     /// lock is released before the control returns to the caller.
-    pub(crate) fn idx_to_struct_name(
-        &self,
-        idx: StructNameIndex,
-    ) -> PartialVMResult<StructIdentifier> {
+    pub fn idx_to_struct_name(&self, idx: StructNameIndex) -> PartialVMResult<StructIdentifier> {
         let index_map = self.0.read();
         Ok(Self::idx_to_struct_name_helper(&index_map, idx)?
             .as_ref()
@@ -109,7 +133,7 @@ impl StructNameIndexMap {
     }
 
     /// Returns the struct tag corresponding to the struct name and the provided type arguments.
-    pub(crate) fn idx_to_struct_tag(
+    pub fn idx_to_struct_tag(
         &self,
         idx: StructNameIndex,
         ty_args: Vec<TypeTag>,
@@ -126,7 +150,7 @@ impl StructNameIndexMap {
 
     /// Returns the number of cached entries. Asserts that the number of cached indices is equal to
     /// the number of cached struct names.
-    pub(crate) fn checked_len(&self) -> PartialVMResult<usize> {
+    pub fn checked_len(&self) -> PartialVMResult<usize> {
         let (forward_map_len, backward_map_len) = {
             let index_map = self.0.read();
             (index_map.forward_map.len(), index_map.backward_map.len())
@@ -145,7 +169,6 @@ impl StructNameIndexMap {
     }
 }
 
-// Only used by V1 loader.
 impl Clone for StructNameIndexMap {
     fn clone(&self) -> Self {
         Self(RwLock::new(self.0.read().clone()))
@@ -171,7 +194,7 @@ mod test {
     #[test]
     fn test_index_map_must_contain_idx() {
         let struct_name_idx_map = StructNameIndexMap::empty();
-        assert_err!(struct_name_idx_map.idx_to_struct_name_ref(StructNameIndex(0)));
+        assert_err!(struct_name_idx_map.idx_to_struct_name_ref(StructNameIndex::new(0)));
     }
 
     #[test]