diff --git a/identity_iota_core/src/rebased/assets/asset.rs b/identity_iota_core/src/rebased/assets/asset.rs
index 525cefb5f..866bf9be2 100644
--- a/identity_iota_core/src/rebased/assets/asset.rs
+++ b/identity_iota_core/src/rebased/assets/asset.rs
@@ -24,7 +24,6 @@ use iota_sdk::types::base_types::SequenceNumber;
 use iota_sdk::types::id::UID;
 use iota_sdk::types::object::Owner;
 use iota_sdk::types::TypeTag;
-use iota_sdk::IotaClient;
 use move_core_types::ident_str;
 use move_core_types::language_storage::StructTag;
 use secret_storage::Signer;
@@ -69,7 +68,7 @@ where
   T: DeserializeOwned,
 {
   /// Resolves an [`AuthenticatedAsset`] by its ID `id`.
-  pub async fn get_by_id(id: ObjectID, client: &IotaClient) -> Result<Self, Error> {
+  pub async fn get_by_id<S>(id: ObjectID, client: &IdentityClient<S>) -> Result<Self, Error> {
     let res = client
       .read_api()
       .get_object_with_options(id, IotaObjectDataOptions::new().with_content())
@@ -89,7 +88,7 @@ where
 }
 
 impl<T> AuthenticatedAsset<T> {
-  async fn object_ref(&self, client: &IotaClient) -> Result<ObjectRef, Error> {
+  async fn object_ref<S>(&self, client: &IdentityClient<S>) -> Result<ObjectRef, Error> {
     client
       .read_api()
       .get_object_with_options(self.id(), IotaObjectDataOptions::default())
@@ -259,7 +258,7 @@ impl MoveType for TransferProposal {
 
 impl TransferProposal {
   /// Resolves a [`TransferProposal`] by its ID `id`.
-  pub async fn get_by_id(id: ObjectID, client: &IotaClient) -> Result<Self, Error> {
+  pub async fn get_by_id<S>(id: ObjectID, client: &IdentityClient<S>) -> Result<Self, Error> {
     let res = client
       .read_api()
       .get_object_with_options(id, IotaObjectDataOptions::new().with_content())
@@ -294,7 +293,7 @@ impl TransferProposal {
       })
   }
 
-  async fn asset_metadata(&self, client: &IotaClient) -> anyhow::Result<(ObjectRef, TypeTag)> {
+  async fn asset_metadata<S>(&self, client: &IdentityClient<S>) -> anyhow::Result<(ObjectRef, TypeTag)> {
     let res = client
       .read_api()
       .get_object_with_options(self.asset_id, IotaObjectDataOptions::default().with_type())
@@ -318,7 +317,7 @@ impl TransferProposal {
     Ok((asset_ref, param_type))
   }
 
-  async fn initial_shared_version(&self, client: &IotaClient) -> anyhow::Result<SequenceNumber> {
+  async fn initial_shared_version<S>(&self, client: &IdentityClient<S>) -> anyhow::Result<SequenceNumber> {
     let owner = client
       .read_api()
       .get_object_with_options(*self.id.object_id(), IotaObjectDataOptions::default().with_owner())
diff --git a/identity_iota_core/src/rebased/client/full_client.rs b/identity_iota_core/src/rebased/client/full_client.rs
index 0a43c288b..1aa7b70e4 100644
--- a/identity_iota_core/src/rebased/client/full_client.rs
+++ b/identity_iota_core/src/rebased/client/full_client.rs
@@ -102,7 +102,7 @@ impl<S> Deref for IdentityClient<S> {
 
 impl<S> IdentityClient<S>
 where
-  S: Signer<IotaKeySignature>,
+  S: Signer<IotaKeySignature> + Sync,
 {
   pub async fn new(client: IdentityClientReadOnly, signer: S) -> Result<Self, Error> {
     let public_key = signer
diff --git a/identity_iota_core/src/rebased/error.rs b/identity_iota_core/src/rebased/error.rs
index e537e22a9..c2fd24b51 100644
--- a/identity_iota_core/src/rebased/error.rs
+++ b/identity_iota_core/src/rebased/error.rs
@@ -65,4 +65,7 @@ pub enum Error {
   /// An error caused by either a connection issue or an invalid RPC call.
   #[error("RPC error: {0}")]
   RpcError(String),
+  /// An error caused by a bcs serialization or deserialization.
+  #[error("BCS error: {0}")]
+  BcsError(#[from] bcs::Error),
 }