diff --git a/java/lance-jni/src/blocking_dataset.rs b/java/lance-jni/src/blocking_dataset.rs
index ee8de347ad7..aa56d54de95 100644
--- a/java/lance-jni/src/blocking_dataset.rs
+++ b/java/lance-jni/src/blocking_dataset.rs
@@ -631,6 +631,7 @@ fn create_dataset<'local>(
         &storage_options_obj,
         &initial_bases,
         &target_bases,
+        &JObject::null(), // allow_external_blob_outside_bases not used for Dataset.write()
     )?;
 
     // Set up namespace commit handler and storage options provider if namespace is provided
diff --git a/java/lance-jni/src/fragment.rs b/java/lance-jni/src/fragment.rs
index 05b72c58a51..3b2a7ba6b22 100644
--- a/java/lance-jni/src/fragment.rs
+++ b/java/lance-jni/src/fragment.rs
@@ -89,15 +89,16 @@ pub extern "system" fn Java_org_lance_Fragment_createWithFfiArray<'local>(
     dataset_uri: JString,
     arrow_array_addr: jlong,
     arrow_schema_addr: jlong,
-    max_rows_per_file: JObject,     // Optional<Integer>
-    max_rows_per_group: JObject,    // Optional<Integer>
-    max_bytes_per_file: JObject,    // Optional<Long>
-    mode: JObject,                  // Optional<String>
-    enable_stable_row_ids: JObject, // Optional<Boolean>
-    data_storage_version: JObject,  // Optional<String>
-    storage_options_obj: JObject,   // Map<String, String>
-    namespace_obj: JObject,         // LanceNamespace (can be null)
-    table_id_obj: JObject,          // List<String> (can be null)
+    max_rows_per_file: JObject,                 // Optional<Integer>
+    max_rows_per_group: JObject,                // Optional<Integer>
+    max_bytes_per_file: JObject,                // Optional<Long>
+    mode: JObject,                              // Optional<String>
+    enable_stable_row_ids: JObject,             // Optional<Boolean>
+    data_storage_version: JObject,              // Optional<String>
+    storage_options_obj: JObject,               // Map<String, String>
+    namespace_obj: JObject,                     // LanceNamespace (can be null)
+    table_id_obj: JObject,                      // List<String> (can be null)
+    allow_external_blob_outside_bases: JObject, // Optional<Boolean>
 ) -> JObject<'local> {
     ok_or_throw_with_return!(
         env,
@@ -115,6 +116,7 @@ pub extern "system" fn Java_org_lance_Fragment_createWithFfiArray<'local>(
             storage_options_obj,
             namespace_obj,
             table_id_obj,
+            allow_external_blob_outside_bases,
         ),
         JObject::default()
     )
@@ -126,15 +128,16 @@ fn inner_create_with_ffi_array<'local>(
     dataset_uri: JString,
     arrow_array_addr: jlong,
     arrow_schema_addr: jlong,
-    max_rows_per_file: JObject,     // Optional<Integer>
-    max_rows_per_group: JObject,    // Optional<Integer>
-    max_bytes_per_file: JObject,    // Optional<Long>
-    mode: JObject,                  // Optional<String>
-    enable_stable_row_ids: JObject, // Optional<Boolean>
-    data_storage_version: JObject,  // Optional<String>
-    storage_options_obj: JObject,   // Map<String, String>
-    namespace_obj: JObject,         // LanceNamespace (can be null)
-    table_id_obj: JObject,          // List<String> (can be null)
+    max_rows_per_file: JObject,                 // Optional<Integer>
+    max_rows_per_group: JObject,                // Optional<Integer>
+    max_bytes_per_file: JObject,                // Optional<Long>
+    mode: JObject,                              // Optional<String>
+    enable_stable_row_ids: JObject,             // Optional<Boolean>
+    data_storage_version: JObject,              // Optional<String>
+    storage_options_obj: JObject,               // Map<String, String>
+    namespace_obj: JObject,                     // LanceNamespace (can be null)
+    table_id_obj: JObject,                      // List<String> (can be null)
+    allow_external_blob_outside_bases: JObject, // Optional<Boolean>
 ) -> Result<JObject<'local>> {
     let c_array_ptr = arrow_array_addr as *mut FFI_ArrowArray;
     let c_schema_ptr = arrow_schema_addr as *mut FFI_ArrowSchema;
@@ -161,6 +164,7 @@ fn inner_create_with_ffi_array<'local>(
         storage_options_obj,
         namespace_obj,
         table_id_obj,
+        allow_external_blob_outside_bases,
         reader,
     )
 }
@@ -171,15 +175,16 @@ pub extern "system" fn Java_org_lance_Fragment_createWithFfiStream<'a>(
     _obj: JObject,
     dataset_uri: JString,
     arrow_array_stream_addr: jlong,
-    max_rows_per_file: JObject,     // Optional<Integer>
-    max_rows_per_group: JObject,    // Optional<Integer>
-    max_bytes_per_file: JObject,    // Optional<Long>
-    mode: JObject,                  // Optional<String>
-    enable_stable_row_ids: JObject, // Optional<Boolean>
-    data_storage_version: JObject,  // Optional<String>
-    storage_options_obj: JObject,   // Map<String, String>
-    namespace_obj: JObject,         // LanceNamespace (can be null)
-    table_id_obj: JObject,          // List<String> (can be null)
+    max_rows_per_file: JObject,                 // Optional<Integer>
+    max_rows_per_group: JObject,                // Optional<Integer>
+    max_bytes_per_file: JObject,                // Optional<Long>
+    mode: JObject,                              // Optional<String>
+    enable_stable_row_ids: JObject,             // Optional<Boolean>
+    data_storage_version: JObject,              // Optional<String>
+    storage_options_obj: JObject,               // Map<String, String>
+    namespace_obj: JObject,                     // LanceNamespace (can be null)
+    table_id_obj: JObject,                      // List<String> (can be null)
+    allow_external_blob_outside_bases: JObject, // Optional<Boolean>
 ) -> JObject<'a> {
     ok_or_throw_with_return!(
         env,
@@ -196,6 +201,7 @@ pub extern "system" fn Java_org_lance_Fragment_createWithFfiStream<'a>(
             storage_options_obj,
             namespace_obj,
             table_id_obj,
+            allow_external_blob_outside_bases,
         ),
         JObject::null()
     )
@@ -206,15 +212,16 @@ fn inner_create_with_ffi_stream<'local>(
     env: &mut JNIEnv<'local>,
     dataset_uri: JString,
     arrow_array_stream_addr: jlong,
-    max_rows_per_file: JObject,     // Optional<Integer>
-    max_rows_per_group: JObject,    // Optional<Integer>
-    max_bytes_per_file: JObject,    // Optional<Long>
-    mode: JObject,                  // Optional<String>
-    enable_stable_row_ids: JObject, // Optional<Boolean>
-    data_storage_version: JObject,  // Optional<String>
-    storage_options_obj: JObject,   // Map<String, String>
-    namespace_obj: JObject,         // LanceNamespace (can be null)
-    table_id_obj: JObject,          // List<String> (can be null)
+    max_rows_per_file: JObject,                 // Optional<Integer>
+    max_rows_per_group: JObject,                // Optional<Integer>
+    max_bytes_per_file: JObject,                // Optional<Long>
+    mode: JObject,                              // Optional<String>
+    enable_stable_row_ids: JObject,             // Optional<Boolean>
+    data_storage_version: JObject,              // Optional<String>
+    storage_options_obj: JObject,               // Map<String, String>
+    namespace_obj: JObject,                     // LanceNamespace (can be null)
+    table_id_obj: JObject,                      // List<String> (can be null)
+    allow_external_blob_outside_bases: JObject, // Optional<Boolean>
 ) -> Result<JObject<'local>> {
     let stream_ptr = arrow_array_stream_addr as *mut FFI_ArrowArrayStream;
     let reader = unsafe { ArrowArrayStreamReader::from_raw(stream_ptr) }?;
@@ -231,6 +238,7 @@ fn inner_create_with_ffi_stream<'local>(
         storage_options_obj,
         namespace_obj,
         table_id_obj,
+        allow_external_blob_outside_bases,
         reader,
     )
 }
@@ -239,15 +247,16 @@ fn inner_create_with_ffi_stream<'local>(
 fn create_fragment<'a>(
     env: &mut JNIEnv<'a>,
     dataset_uri: JString,
-    max_rows_per_file: JObject,     // Optional<Integer>
-    max_rows_per_group: JObject,    // Optional<Integer>
-    max_bytes_per_file: JObject,    // Optional<Long>
-    mode: JObject,                  // Optional<String>
-    enable_stable_row_ids: JObject, // Optional<Boolean>
-    data_storage_version: JObject,  // Optional<String>
-    storage_options_obj: JObject,   // Map<String, String>
-    namespace_obj: JObject,         // LanceNamespace (can be null)
-    table_id_obj: JObject,          // List<String> (can be null)
+    max_rows_per_file: JObject,                 // Optional<Integer>
+    max_rows_per_group: JObject,                // Optional<Integer>
+    max_bytes_per_file: JObject,                // Optional<Long>
+    mode: JObject,                              // Optional<String>
+    enable_stable_row_ids: JObject,             // Optional<Boolean>
+    data_storage_version: JObject,              // Optional<String>
+    storage_options_obj: JObject,               // Map<String, String>
+    namespace_obj: JObject,                     // LanceNamespace (can be null)
+    table_id_obj: JObject,                      // List<String> (can be null)
+    allow_external_blob_outside_bases: JObject, // Optional<Boolean>
     source: impl StreamingWriteSource,
 ) -> Result<JObject<'a>> {
     let path_str = dataset_uri.extract(env)?;
@@ -264,6 +273,7 @@ fn create_fragment<'a>(
         &storage_options_obj,
         &JObject::null(), // not used when creating fragments
         &JObject::null(), // not used when creating fragments
+        &allow_external_blob_outside_bases,
     )?;
 
     // Set up storage options provider if namespace is provided
diff --git a/java/lance-jni/src/utils.rs b/java/lance-jni/src/utils.rs
index 113769dd17f..3d7ef2ebdaf 100644
--- a/java/lance-jni/src/utils.rs
+++ b/java/lance-jni/src/utils.rs
@@ -49,8 +49,9 @@ pub fn extract_write_params(
     data_storage_version: &JObject,
     enable_v2_manifest_paths: Option<&JObject>,
     storage_options_obj: &JObject,
-    initial_bases: &JObject, // Optional<BasePath>
-    target_bases: &JObject,  // Optional<String>
+    initial_bases: &JObject,                     // Optional<BasePath>
+    target_bases: &JObject,                      // Optional<String>
+    allow_external_blob_outside_bases: &JObject, // Optional<Boolean>
 ) -> Result<WriteParams> {
     let mut write_params = WriteParams::default();
 
@@ -97,6 +98,10 @@ pub fn extract_write_params(
         write_params.target_base_names_or_paths = Some(names);
     }
 
+    if let Some(allow) = env.get_boolean_opt(allow_external_blob_outside_bases)? {
+        write_params.allow_external_blob_outside_bases = allow;
+    }
+
     // Create storage options accessor from static storage_options
     let accessor = if storage_options.is_empty() {
         None
diff --git a/java/src/main/java/org/lance/Fragment.java b/java/src/main/java/org/lance/Fragment.java
index 367e03b58d4..89a61560561 100644
--- a/java/src/main/java/org/lance/Fragment.java
+++ b/java/src/main/java/org/lance/Fragment.java
@@ -279,7 +279,8 @@ static List<FragmentMetadata> create(
           params.getDataStorageVersion(),
           params.getStorageOptions(),
           namespaceClient,
-          tableId);
+          tableId,
+          params.getAllowExternalBlobOutsideBases());
     }
   }
 
@@ -304,7 +305,8 @@ static List<FragmentMetadata> create(
         params.getDataStorageVersion(),
         params.getStorageOptions(),
         namespaceClient,
-        tableId);
+        tableId,
+        params.getAllowExternalBlobOutsideBases());
   }
 
   /** Create a fragment from the given arrow array and schema. */
@@ -320,7 +322,8 @@ private static native List<FragmentMetadata> createWithFfiArray(
       Optional<String> dataStorageVersion,
       Map<String, String> storageOptions,
       LanceNamespace namespaceClient,
-      List<String> tableId);
+      List<String> tableId,
+      Optional<Boolean> allowExternalBlobOutsideBases);
 
   /** Create a fragment from the given arrow stream. */
   private static native List<FragmentMetadata> createWithFfiStream(
@@ -334,5 +337,6 @@ private static native List<FragmentMetadata> createWithFfiStream(
       Optional<String> dataStorageVersion,
       Map<String, String> storageOptions,
       LanceNamespace namespaceClient,
-      List<String> tableId);
+      List<String> tableId,
+      Optional<Boolean> allowExternalBlobOutsideBases);
 }
diff --git a/java/src/main/java/org/lance/WriteParams.java b/java/src/main/java/org/lance/WriteParams.java
index 8a04a5d5b96..6f5d4545ca9 100644
--- a/java/src/main/java/org/lance/WriteParams.java
+++ b/java/src/main/java/org/lance/WriteParams.java
@@ -40,6 +40,7 @@ public enum WriteMode {
   private Map<String, String> storageOptions = new HashMap<>();
   private final Optional<List<BasePath>> initialBases;
   private final Optional<List<String>> targetBases;
+  private final Optional<Boolean> allowExternalBlobOutsideBases;
 
   private WriteParams(
       Optional<Integer> maxRowsPerFile,
@@ -51,7 +52,8 @@ private WriteParams(
       Optional<Boolean> enableV2ManifestPaths,
       Map<String, String> storageOptions,
       Optional<List<BasePath>> initialBases,
-      Optional<List<String>> targetBases) {
+      Optional<List<String>> targetBases,
+      Optional<Boolean> allowExternalBlobOutsideBases) {
     this.maxRowsPerFile = maxRowsPerFile;
     this.maxRowsPerGroup = maxRowsPerGroup;
     this.maxBytesPerFile = maxBytesPerFile;
@@ -62,6 +64,7 @@ private WriteParams(
     this.storageOptions = storageOptions;
     this.initialBases = initialBases;
     this.targetBases = targetBases;
+    this.allowExternalBlobOutsideBases = allowExternalBlobOutsideBases;
   }
 
   public Optional<Integer> getMaxRowsPerFile() {
@@ -109,6 +112,18 @@ public Optional<List<String>> getTargetBases() {
     return targetBases;
   }
 
+  /**
+   * Get whether external blob URIs outside registered bases are allowed.
+   *
+   * <p>When true, blob v2 columns can reference external URIs that are not under any registered
+   * base path. The URI is stored as an absolute external reference with base_id=0.
+   *
+   * @return Optional containing the setting, or empty if not set
+   */
+  public Optional<Boolean> getAllowExternalBlobOutsideBases() {
+    return allowExternalBlobOutsideBases;
+  }
+
   @Override
   public String toString() {
     return MoreObjects.toStringHelper(this)
@@ -132,6 +147,7 @@ public static class Builder {
     private Map<String, String> storageOptions = new HashMap<>();
     private Optional<List<BasePath>> initialBases = Optional.empty();
     private Optional<List<String>> targetBases = Optional.empty();
+    private Optional<Boolean> allowExternalBlobOutsideBases = Optional.empty();
 
     public Builder withMaxRowsPerFile(int maxRowsPerFile) {
       this.maxRowsPerFile = Optional.of(maxRowsPerFile);
@@ -183,6 +199,21 @@ public Builder withTargetBases(List<String> targetBases) {
       return this;
     }
 
+    /**
+     * Allow external blob URIs outside registered bases.
+     *
+     * <p>When true, blob v2 columns can reference external URIs (e.g. pointing to blob files in
+     * another Lance dataset) that are not under any registered base path. The URI is stored as an
+     * absolute external reference with base_id=0.
+     *
+     * @param allow true to allow external blob URIs outside bases
+     * @return this builder
+     */
+    public Builder withAllowExternalBlobOutsideBases(boolean allow) {
+      this.allowExternalBlobOutsideBases = Optional.of(allow);
+      return this;
+    }
+
     public WriteParams build() {
       return new WriteParams(
           maxRowsPerFile,
@@ -194,7 +225,8 @@ public WriteParams build() {
           enableV2ManifestPaths,
           storageOptions,
           initialBases,
-          targetBases);
+          targetBases,
+          allowExternalBlobOutsideBases);
     }
   }
 }