diff --git a/api.json b/api.json
index 22b55a5..cc18a50 100644
--- a/api.json
+++ b/api.json
@@ -1,7 +1,7 @@
 {
  "openapi":"3.0.2",
  "info": {
-   "version":"1.4.9",
+   "version":"1.4.10",
    "title":"Rosetta",
    "description":"Build Once. Integrate Your Blockchain Everywhere.",
    "license": {
@@ -1056,6 +1056,12 @@
              "$ref":"#/components/schemas/Operation"
             }
           },
+         "related_transactions": {
+           "type":"array",
+           "items": {
+             "$ref":"#/components/schemas/RelatedTransaction"
+            }
+          },
          "metadata": {
            "description":"Transactions that are related to other transactions (like a cross-shard transaction) should include the tranaction_identifier of these transactions in the metadata.",
            "type":"object",
@@ -1557,6 +1563,33 @@
           }
         }
       },
+     "RelatedTransaction": {
+       "description":"The related_transaction allows implementations to link together multiple transactions. An unpopulated network identifier indicates that the related transaction is on the same network.",
+       "type":"object",
+       "required": [
+         "transaction_identifier",
+         "direction"
+        ],
+       "properties": {
+         "network_identifier": {
+           "$ref":"#/components/schemas/NetworkIdentifier"
+          },
+         "transaction_identifier": {
+           "$ref":"#/components/schemas/TransactionIdentifier"
+          },
+         "direction": {
+           "$ref":"#/components/schemas/Direction"
+          }
+        }
+      },
+     "Direction": {
+       "description":"Used by RelatedTransaction to indicate the direction of the relation (i.e. cross-shard/cross-network sends may reference `backward` to an earlier transaction and async execution may reference `forward`). Can be used to indicate if a transaction relation is from child to parent or the reverse.",
+       "type":"string",
+       "enum": [
+         "forward",
+         "backward"
+        ]
+      },
      "AccountBalanceRequest": {
        "description":"An AccountBalanceRequest is utilized to make a balance request on the /account/balance endpoint. If the block_identifier is populated, a historical balance query should be performed.",
        "type":"object",
diff --git a/api.yaml b/api.yaml
index 46e3bab..8605f98 100644
--- a/api.yaml
+++ b/api.yaml
@@ -14,7 +14,7 @@
 
 openapi: 3.0.2
 info:
-  version: 1.4.9
+  version: 1.4.10
   title: Rosetta
   description: |
     Build Once. Integrate Your Blockchain Everywhere.
@@ -801,6 +801,10 @@ components:
       $ref: 'models/Operator.yaml'
     BlockTransaction:
       $ref: 'models/BlockTransaction.yaml'
+    RelatedTransaction:
+      $ref: 'models/RelatedTransaction.yaml'
+    Direction:
+      $ref: 'models/Direction.yaml'
 
     # Request/Responses
     AccountBalanceRequest:
diff --git a/models/Direction.yaml b/models/Direction.yaml
new file mode 100644
index 0000000..086de44
--- /dev/null
+++ b/models/Direction.yaml
@@ -0,0 +1,21 @@
+# Copyright 2020 Coinbase, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+description: |
+  Used by RelatedTransaction to indicate the direction of the relation (i.e. cross-shard/cross-network sends may
+  reference `backward` to an earlier transaction and async execution may reference `forward`). Can be used to indicate if
+  a transaction relation is from child to parent or the reverse.
+type: string
+enum:
+  - forward
+  - backward
\ No newline at end of file
diff --git a/models/RelatedTransaction.yaml b/models/RelatedTransaction.yaml
new file mode 100644
index 0000000..5d68d1a
--- /dev/null
+++ b/models/RelatedTransaction.yaml
@@ -0,0 +1,28 @@
+# Copyright 2020 Coinbase, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+description: |
+  The related_transaction allows implementations to link together multiple transactions.
+  An unpopulated network identifier indicates that the related transaction is on the same network.
+type: object
+required:
+  - transaction_identifier
+  - direction
+properties:
+  network_identifier:
+    $ref: 'NetworkIdentifier.yaml'
+  transaction_identifier:
+    $ref: 'TransactionIdentifier.yaml'
+  direction:
+    $ref: 'Direction.yaml'
diff --git a/models/Transaction.yaml b/models/Transaction.yaml
index b808d34..5e9d81c 100644
--- a/models/Transaction.yaml
+++ b/models/Transaction.yaml
@@ -26,6 +26,10 @@ properties:
     type: array
     items:
       $ref: 'Operation.yaml'
+  related_transactions:
+    type: array
+    items:
+      $ref: 'RelatedTransaction.yaml'
   metadata:
     description: |
       Transactions that are related to other transactions (like a cross-shard transaction) should include