diff --git a/sync-server/src/app_state/database.rs b/sync-server/src/app_state/database.rs
index 9fa76234..a3273724 100644
--- a/sync-server/src/app_state/database.rs
+++ b/sync-server/src/app_state/database.rs
@@ -443,6 +443,7 @@ impl Database {
             r#"
             select
                 vault_update_id,
+                creation_vault_update_id,
                 document_id as "document_id: Hyphenated",
                 relative_path,
                 updated_date as "updated_date: chrono::DateTime<Utc>",
@@ -474,6 +475,7 @@ impl Database {
                     user_id: row.user_id,
                     device_id: row.device_id,
                     content_size: row.content_size.unwrap_or(0),
+                    is_new_file: row.creation_vault_update_id == row.vault_update_id,
                 })
                 .collect()
         })
@@ -491,6 +493,7 @@ impl Database {
             r#"
             select
                 vault_update_id,
+                creation_vault_update_id,
                 document_id as "document_id: Hyphenated",
                 relative_path,
                 updated_date as "updated_date: chrono::DateTime<Utc>",
@@ -526,6 +529,7 @@ impl Database {
                     user_id: row.user_id,
                     device_id: row.device_id,
                     content_size: row.content_size.unwrap_or(0),
+                    is_new_file: row.creation_vault_update_id == row.vault_update_id,
                 })
                 .collect()
         })
@@ -750,6 +754,7 @@ impl Database {
             r#"
             select
                 vault_update_id,
+                creation_vault_update_id,
                 document_id as "document_id: Hyphenated",
                 relative_path,
                 updated_date as "updated_date: chrono::DateTime<Utc>",
@@ -783,6 +788,7 @@ impl Database {
                     user_id: row.user_id,
                     device_id: row.device_id,
                     content_size: row.content_size.unwrap_or(0),
+                    is_new_file: row.creation_vault_update_id == row.vault_update_id,
                 })
                 .collect()
         })
@@ -805,6 +811,7 @@ impl Database {
             user_id: row.user_id,
             device_id: row.device_id,
             content_size: row.content_size.unwrap_or(0),
+            is_new_file: row.creation_vault_update_id == row.vault_update_id,
         };
 
         if let Some(before) = before_update_id {
@@ -813,6 +820,7 @@ impl Database {
                 r#"
                 select
                     vault_update_id,
+                    creation_vault_update_id,
                     document_id as "document_id: Hyphenated",
                     relative_path,
                     updated_date as "updated_date: chrono::DateTime<Utc>",
@@ -845,6 +853,7 @@ impl Database {
                 r#"
                 select
                     vault_update_id,
+                    creation_vault_update_id,
                     document_id as "document_id: Hyphenated",
                     relative_path,
                     updated_date as "updated_date: chrono::DateTime<Utc>",
diff --git a/sync-server/src/app_state/database/models.rs b/sync-server/src/app_state/database/models.rs
index b0e19c49..89867067 100644
--- a/sync-server/src/app_state/database/models.rs
+++ b/sync-server/src/app_state/database/models.rs
@@ -46,10 +46,14 @@ pub struct DocumentVersionWithoutContent {
 
     #[ts(type = "number")]
     pub content_size: u64,
+
+    /// True iff this is the first version of the document
+    pub is_new_file: bool,
 }
 
 impl From<StoredDocumentVersion> for DocumentVersionWithoutContent {
     fn from(value: StoredDocumentVersion) -> Self {
+        let is_new_file = value.creation_vault_update_id == value.vault_update_id;
         Self {
             vault_update_id: value.vault_update_id,
             document_id: value.document_id,
@@ -59,6 +63,7 @@ impl From<StoredDocumentVersion> for DocumentVersionWithoutContent {
             user_id: value.user_id,
             device_id: value.device_id,
             content_size: value.content.len() as u64,
+            is_new_file,
         }
     }
 }
@@ -82,6 +87,7 @@ pub struct DocumentVersion {
 #[derive(Debug)]
 pub struct VaultHistoryRow {
     pub vault_update_id: VaultUpdateId,
+    pub creation_vault_update_id: VaultUpdateId,
     pub document_id: DocumentId,
     pub relative_path: String,
     pub updated_date: DateTime<Utc>,
diff --git a/sync-server/src/server/create_document.rs b/sync-server/src/server/create_document.rs
index 8230ea46..f1780143 100644
--- a/sync-server/src/server/create_document.rs
+++ b/sync-server/src/server/create_document.rs
@@ -89,7 +89,7 @@ pub async fn create_document(
                     Vec::new(),
                     vault_id,
                     latest_version.document_id,
-                    &request.relative_path,
+                    Some(&request.relative_path),
                     new_content,
                     user,
                     device_id,
diff --git a/sync-server/src/server/requests.rs b/sync-server/src/server/requests.rs
index e0468edc..232e514d 100644
--- a/sync-server/src/server/requests.rs
+++ b/sync-server/src/server/requests.rs
@@ -22,7 +22,9 @@ pub struct CreateDocumentVersion {
 #[derive(Debug, TryFromMultipart)]
 pub struct UpdateBinaryDocumentVersion {
     pub parent_version_id: VaultUpdateId,
-    pub relative_path: String,
+    // None on a content-only edit; Some on a user rename. When None,
+    // the server keeps the document at its current path.
+    pub relative_path: Option<String>,
 
     #[form_data(limit = "unlimited")]
     pub content: FieldData<Bytes>,
@@ -35,7 +37,9 @@ pub struct UpdateTextDocumentVersion {
     #[ts(type = "number")]
     pub parent_version_id: VaultUpdateId,
 
-    pub relative_path: String,
+    // None on a content-only edit; Some on a user rename. When None,
+    // the server keeps the document at its current path.
+    pub relative_path: Option<String>,
 
     #[ts(type = "Array<number | string>")]
     pub content: Vec<NumberOrText>,
diff --git a/sync-server/src/server/update_document.rs b/sync-server/src/server/update_document.rs
index 8b9c3bf5..5e86055d 100644
--- a/sync-server/src/server/update_document.rs
+++ b/sync-server/src/server/update_document.rs
@@ -66,7 +66,7 @@ pub async fn update_binary(
         parent_document.content,
         vault_id,
         document_id,
-        &request.relative_path,
+        request.relative_path.as_deref(),
         content,
         user,
         device_id,
@@ -112,7 +112,7 @@ pub async fn update_text(
         parent_document.content,
         vault_id,
         document_id,
-        &request.relative_path,
+        request.relative_path.as_deref(),
         content,
         user,
         device_id,
@@ -157,7 +157,7 @@ pub async fn update_document(
     parent_content: Vec<u8>,
     vault_id: VaultId,
     document_id: DocumentId,
-    relative_path: &str,
+    relative_path: Option<&str>,
     content: Vec<u8>,
     user: User,
     device_id: DeviceIdHeader,
@@ -166,7 +166,10 @@ pub async fn update_document(
 ) -> Result<Json<DocumentUpdateResponse>, SyncServerError> {
     debug!("Updating document `{document_id}` in vault `{vault_id}`");
 
-    let sanitized_relative_path = sanitize_path(relative_path).map_err(client_error)?;
+    let sanitized_relative_path = relative_path
+        .map(sanitize_path)
+        .transpose()
+        .map_err(client_error)?;
 
     let last_update_id = state
         .database
@@ -202,9 +205,12 @@ pub async fn update_document(
     }
 
     // Return the latest version if the content and path are the same as the latest
-    // version
-    if content == latest_version.content && sanitized_relative_path == latest_version.relative_path
-    {
+    // version. A missing relative_path means "keep current path", so the path
+    // is implicitly unchanged.
+    let path_unchanged = sanitized_relative_path
+        .as_deref()
+        .is_none_or(|p| p == latest_version.relative_path);
+    if content == latest_version.content && path_unchanged {
         info!(
             "Document content is the same as the latest version for `{document_id}`, skipping update"
         );
@@ -219,8 +225,14 @@ pub async fn update_document(
         )));
     }
 
+    // For mergability, use whichever path the new version will live at — the
+    // requested rename target if the client sent one, otherwise the existing
+    // server-side path.
+    let mergable_check_path = sanitized_relative_path
+        .as_deref()
+        .unwrap_or(&latest_version.relative_path);
     let are_all_participants_mergable = is_file_type_mergable(
-        &sanitized_relative_path,
+        mergable_check_path,
         &state.config.server.mergeable_file_extensions,
     ) && !is_binary(&parent_content)
         && !is_binary(&latest_version.content)
@@ -263,33 +275,36 @@ pub async fn update_document(
         (content, false) // false means that the client doesn't need to refetch the file as we can ensure the remote and local versions are the same as LWW is the merging method for binary files
     };
 
-    // Rename resolution: only apply the client's rename if the document's path
-    // hasn't changed since this client's parent version. Check the parent
-    // version's path against the latest version's path. If they differ, another
-    // client already renamed the document — keep the latest path (first rename
-    // wins). Content changes from both clients are still merged correctly via
-    // the 3-way reconcile above, independent of which rename wins.
-    let new_relative_path = if parent_relative_path == latest_version.relative_path
-        && sanitized_relative_path != latest_version.relative_path
-    {
-        let new_path = find_first_available_path(
-            &vault_id,
-            &sanitized_relative_path,
-            &state.database,
-            &mut transaction,
-        )
-        .await
-        .map_err(server_error)?;
+    // Rename resolution: only apply the client's rename if (a) the client
+    // requested one (`sanitized_relative_path` is `Some`) and (b) the
+    // document's path hasn't changed since this client's parent version.
+    // If the parent and latest paths differ, another client already renamed
+    // the document — keep the latest path (first rename wins). Content
+    // changes from both clients are still merged correctly via the 3-way
+    // reconcile above, independent of which rename wins. A missing
+    // relative_path means "keep current path" (content-only edit).
+    let new_relative_path = match sanitized_relative_path.as_deref() {
+        Some(requested) if parent_relative_path == latest_version.relative_path
+            && requested != latest_version.relative_path =>
+        {
+            let new_path = find_first_available_path(
+                &vault_id,
+                requested,
+                &state.database,
+                &mut transaction,
+            )
+            .await
+            .map_err(server_error)?;
 
-        if new_path != sanitized_relative_path {
-            info!(
-                "Document already exists at new location: `{sanitized_relative_path}` when trying to update it in vault `{vault_id}`, deconflicting by creating at `{new_path}`"
-            );
+            if new_path != requested {
+                info!(
+                    "Document already exists at new location: `{requested}` when trying to update it in vault `{vault_id}`, deconflicting by creating at `{new_path}`"
+                );
+            }
+
+            new_path
         }
-
-        new_path
-    } else {
-        latest_version.relative_path.clone()
+        _ => latest_version.relative_path.clone(),
     };
 
     let new_version = StoredDocumentVersion {