diff --git a/messages/src/decorators/attachment.rs b/messages/src/decorators/attachment.rs
index 8f867c0289..203a39ba32 100644
--- a/messages/src/decorators/attachment.rs
+++ b/messages/src/decorators/attachment.rs
@@ -1,7 +1,6 @@
 use chrono::{DateTime, Utc};
 use serde::{Deserialize, Serialize};
 use serde_json::Value;
-use shared_vcx::maybe_known::MaybeKnown;
 use typed_builder::TypedBuilder;
 use url::Url;
 
@@ -59,22 +58,6 @@ pub enum AttachmentType {
     Links(Vec<Url>),
 }
 
-#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, TypedBuilder)]
-#[serde(rename_all = "snake_case")]
-pub struct AttachmentFormatSpecifier<F> {
-    pub attach_id: String,
-    pub format: MaybeKnown<F>,
-}
-
-#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, TypedBuilder)]
-#[serde(rename_all = "snake_case")]
-pub struct OptionalIdAttachmentFormatSpecifier<F> {
-    #[builder(default)]
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub attach_id: Option<String>,
-    pub format: MaybeKnown<F>,
-}
-
 #[cfg(test)]
 #[allow(clippy::unwrap_used)]
 #[allow(clippy::field_reassign_with_default)]
diff --git a/messages/src/lib.rs b/messages/src/lib.rs
index f19daadac4..46ea11b5f9 100644
--- a/messages/src/lib.rs
+++ b/messages/src/lib.rs
@@ -17,8 +17,8 @@ use derive_more::From;
 use misc::utils;
 use msg_fields::protocols::{
     cred_issuance::{v1::CredentialIssuanceV1, v2::CredentialIssuanceV2, CredentialIssuance},
-    present_proof::{v2::PresentProofV2, PresentProof},
     pickup::Pickup,
+    present_proof::{v2::PresentProofV2, PresentProof},
 };
 use msg_types::{
     cred_issuance::CredentialIssuanceType, present_proof::PresentProofType,
diff --git a/messages/src/msg_fields/protocols/common/attachment_format_specifier.rs b/messages/src/msg_fields/protocols/common/attachment_format_specifier.rs
new file mode 100644
index 0000000000..1bf91efc5d
--- /dev/null
+++ b/messages/src/msg_fields/protocols/common/attachment_format_specifier.rs
@@ -0,0 +1,23 @@
+use serde::{Deserialize, Serialize};
+use shared_vcx::maybe_known::MaybeKnown;
+use typed_builder::TypedBuilder;
+
+/// Specifies that a particular Attachment, with the id of `attach_id`, has the format of `format`.
+#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, TypedBuilder)]
+#[serde(rename_all = "snake_case")]
+pub struct AttachmentFormatSpecifier<F> {
+    pub attach_id: String,
+    pub format: MaybeKnown<F>,
+}
+
+/// If `attach_id` is not [None], this specifies that a particular Attachment, with the id of
+/// `attach_id`, has the format of `format`. If `attach_id` is [None], this structure is used to
+/// indicate that a particular attachment `format` is supported by the sender of the message.
+#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, TypedBuilder)]
+#[serde(rename_all = "snake_case")]
+pub struct OptionalIdAttachmentFormatSpecifier<F> {
+    #[builder(default)]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub attach_id: Option<String>,
+    pub format: MaybeKnown<F>,
+}
diff --git a/messages/src/msg_fields/protocols/common/mod.rs b/messages/src/msg_fields/protocols/common/mod.rs
new file mode 100644
index 0000000000..72073c81b1
--- /dev/null
+++ b/messages/src/msg_fields/protocols/common/mod.rs
@@ -0,0 +1 @@
+pub mod attachment_format_specifier;
diff --git a/messages/src/msg_fields/protocols/cred_issuance/v2/issue_credential.rs b/messages/src/msg_fields/protocols/cred_issuance/v2/issue_credential.rs
index 03544a3af5..228e07b7c6 100644
--- a/messages/src/msg_fields/protocols/cred_issuance/v2/issue_credential.rs
+++ b/messages/src/msg_fields/protocols/cred_issuance/v2/issue_credential.rs
@@ -2,12 +2,8 @@ use serde::{Deserialize, Serialize};
 use typed_builder::TypedBuilder;
 
 use crate::{
-    decorators::{
-        attachment::{Attachment, AttachmentFormatSpecifier},
-        please_ack::PleaseAck,
-        thread::Thread,
-        timing::Timing,
-    },
+    decorators::{attachment::Attachment, please_ack::PleaseAck, thread::Thread, timing::Timing},
+    msg_fields::protocols::common::attachment_format_specifier::AttachmentFormatSpecifier,
     msg_parts::MsgParts,
 };
 
diff --git a/messages/src/msg_fields/protocols/cred_issuance/v2/offer_credential.rs b/messages/src/msg_fields/protocols/cred_issuance/v2/offer_credential.rs
index 0d0db70072..f5bb521c43 100644
--- a/messages/src/msg_fields/protocols/cred_issuance/v2/offer_credential.rs
+++ b/messages/src/msg_fields/protocols/cred_issuance/v2/offer_credential.rs
@@ -3,11 +3,8 @@ use typed_builder::TypedBuilder;
 
 use super::CredentialPreviewV2;
 use crate::{
-    decorators::{
-        attachment::{Attachment, AttachmentFormatSpecifier},
-        thread::Thread,
-        timing::Timing,
-    },
+    decorators::{attachment::Attachment, thread::Thread, timing::Timing},
+    msg_fields::protocols::common::attachment_format_specifier::AttachmentFormatSpecifier,
     msg_parts::MsgParts,
 };
 
diff --git a/messages/src/msg_fields/protocols/cred_issuance/v2/propose_credential.rs b/messages/src/msg_fields/protocols/cred_issuance/v2/propose_credential.rs
index ec8b32f43f..54864668e0 100644
--- a/messages/src/msg_fields/protocols/cred_issuance/v2/propose_credential.rs
+++ b/messages/src/msg_fields/protocols/cred_issuance/v2/propose_credential.rs
@@ -3,11 +3,8 @@ use typed_builder::TypedBuilder;
 
 use super::CredentialPreviewV2;
 use crate::{
-    decorators::{
-        attachment::{Attachment, AttachmentFormatSpecifier},
-        thread::Thread,
-        timing::Timing,
-    },
+    decorators::{attachment::Attachment, thread::Thread, timing::Timing},
+    msg_fields::protocols::common::attachment_format_specifier::AttachmentFormatSpecifier,
     msg_parts::MsgParts,
 };
 
diff --git a/messages/src/msg_fields/protocols/cred_issuance/v2/request_credential.rs b/messages/src/msg_fields/protocols/cred_issuance/v2/request_credential.rs
index 811ea24e3b..d4d590129c 100644
--- a/messages/src/msg_fields/protocols/cred_issuance/v2/request_credential.rs
+++ b/messages/src/msg_fields/protocols/cred_issuance/v2/request_credential.rs
@@ -2,11 +2,8 @@ use serde::{Deserialize, Serialize};
 use typed_builder::TypedBuilder;
 
 use crate::{
-    decorators::{
-        attachment::{Attachment, AttachmentFormatSpecifier},
-        thread::Thread,
-        timing::Timing,
-    },
+    decorators::{attachment::Attachment, thread::Thread, timing::Timing},
+    msg_fields::protocols::common::attachment_format_specifier::AttachmentFormatSpecifier,
     msg_parts::MsgParts,
 };
 
diff --git a/messages/src/msg_fields/protocols/mod.rs b/messages/src/msg_fields/protocols/mod.rs
index bae4e6a82c..ae5b4a78ad 100644
--- a/messages/src/msg_fields/protocols/mod.rs
+++ b/messages/src/msg_fields/protocols/mod.rs
@@ -1,4 +1,5 @@
 pub mod basic_message;
+pub mod common;
 pub mod connection;
 pub mod cred_issuance;
 pub mod discover_features;
diff --git a/messages/src/msg_fields/protocols/present_proof/v2/present.rs b/messages/src/msg_fields/protocols/present_proof/v2/present.rs
index 9c6c9b6087..4d1bb76d79 100644
--- a/messages/src/msg_fields/protocols/present_proof/v2/present.rs
+++ b/messages/src/msg_fields/protocols/present_proof/v2/present.rs
@@ -2,12 +2,8 @@ use serde::{Deserialize, Serialize};
 use typed_builder::TypedBuilder;
 
 use crate::{
-    decorators::{
-        attachment::{Attachment, AttachmentFormatSpecifier},
-        please_ack::PleaseAck,
-        thread::Thread,
-        timing::Timing,
-    },
+    decorators::{attachment::Attachment, please_ack::PleaseAck, thread::Thread, timing::Timing},
+    msg_fields::protocols::common::attachment_format_specifier::AttachmentFormatSpecifier,
     msg_parts::MsgParts,
 };
 
diff --git a/messages/src/msg_fields/protocols/present_proof/v2/propose.rs b/messages/src/msg_fields/protocols/present_proof/v2/propose.rs
index 98c83174f1..5342323489 100644
--- a/messages/src/msg_fields/protocols/present_proof/v2/propose.rs
+++ b/messages/src/msg_fields/protocols/present_proof/v2/propose.rs
@@ -2,11 +2,8 @@ use serde::{Deserialize, Serialize};
 use typed_builder::TypedBuilder;
 
 use crate::{
-    decorators::{
-        attachment::{Attachment, OptionalIdAttachmentFormatSpecifier},
-        thread::Thread,
-        timing::Timing,
-    },
+    decorators::{attachment::Attachment, thread::Thread, timing::Timing},
+    msg_fields::protocols::common::attachment_format_specifier::OptionalIdAttachmentFormatSpecifier,
     msg_parts::MsgParts,
 };
 
diff --git a/messages/src/msg_fields/protocols/present_proof/v2/request.rs b/messages/src/msg_fields/protocols/present_proof/v2/request.rs
index 9cf34870cb..c204dce398 100644
--- a/messages/src/msg_fields/protocols/present_proof/v2/request.rs
+++ b/messages/src/msg_fields/protocols/present_proof/v2/request.rs
@@ -2,11 +2,8 @@ use serde::{Deserialize, Serialize};
 use typed_builder::TypedBuilder;
 
 use crate::{
-    decorators::{
-        attachment::{Attachment, AttachmentFormatSpecifier},
-        thread::Thread,
-        timing::Timing,
-    },
+    decorators::{attachment::Attachment, thread::Thread, timing::Timing},
+    msg_fields::protocols::common::attachment_format_specifier::AttachmentFormatSpecifier,
     msg_parts::MsgParts,
 };
 
diff --git a/messages/src/msg_types/registry.rs b/messages/src/msg_types/registry.rs
index d0c77459a2..addd216948 100644
--- a/messages/src/msg_types/registry.rs
+++ b/messages/src/msg_types/registry.rs
@@ -4,21 +4,24 @@ use lazy_static::lazy_static;
 use shared_vcx::maybe_known::MaybeKnown;
 
 use super::{role::Role, Protocol};
-use crate::msg_types::{protocols::{
-    basic_message::BasicMessageTypeV1,
-    connection::ConnectionTypeV1,
-    cred_issuance::{CredentialIssuanceTypeV1, CredentialIssuanceTypeV2},
-    discover_features::DiscoverFeaturesTypeV1,
-    notification::NotificationTypeV1,
-    out_of_band::OutOfBandTypeV1,
-    pickup::PickupTypeV2,
-    present_proof::PresentProofTypeV1,
-    report_problem::ReportProblemTypeV1,
-    revocation::RevocationTypeV2,
-    routing::RoutingTypeV1,
-    signature::SignatureTypeV1,
-    trust_ping::TrustPingTypeV1,
-}, present_proof::PresentProofTypeV2};
+use crate::msg_types::{
+    present_proof::PresentProofTypeV2,
+    protocols::{
+        basic_message::BasicMessageTypeV1,
+        connection::ConnectionTypeV1,
+        cred_issuance::{CredentialIssuanceTypeV1, CredentialIssuanceTypeV2},
+        discover_features::DiscoverFeaturesTypeV1,
+        notification::NotificationTypeV1,
+        out_of_band::OutOfBandTypeV1,
+        pickup::PickupTypeV2,
+        present_proof::PresentProofTypeV1,
+        report_problem::ReportProblemTypeV1,
+        revocation::RevocationTypeV2,
+        routing::RoutingTypeV1,
+        signature::SignatureTypeV1,
+        trust_ping::TrustPingTypeV1,
+    },
+};
 type RegistryMap = HashMap<(&'static str, u8), Vec<RegistryEntry>>;
 
 /// An entry in the protocol registry.