diff --git a/docs/development/core/server/kibana-plugin-core-server.md b/docs/development/core/server/kibana-plugin-core-server.md
index 5450e84417f89b..8ceb4f2090df87 100644
--- a/docs/development/core/server/kibana-plugin-core-server.md
+++ b/docs/development/core/server/kibana-plugin-core-server.md
@@ -270,6 +270,7 @@ The plugin integrates with the core system via lifecycle events: `setup`<!-- -->
 |  [SavedObjectsClientWrapperFactory](./kibana-plugin-core-server.savedobjectsclientwrapperfactory.md) | Describes the factory used to create instances of Saved Objects Client Wrappers. |
 |  [SavedObjectsFieldMapping](./kibana-plugin-core-server.savedobjectsfieldmapping.md) | Describe a [saved object type mapping](./kibana-plugin-core-server.savedobjectstypemappingdefinition.md) field.<!-- -->Please refer to [elasticsearch documentation](https://www.elastic.co/guide/en/elasticsearch/reference/current/mapping-types.html) For the mapping documentation |
 |  [SavedObjectsNamespaceType](./kibana-plugin-core-server.savedobjectsnamespacetype.md) | The namespace type dictates how a saved object can be interacted in relation to namespaces. Each type is mutually exclusive: \* single (default): this type of saved object is namespace-isolated, e.g., it exists in only one namespace. \* multiple: this type of saved object is shareable, e.g., it can exist in one or more namespaces. \* agnostic: this type of saved object is global.<!-- -->Note: do not write logic that uses this value directly; instead, use the appropriate accessors in the [type registry](./kibana-plugin-core-server.savedobjecttyperegistry.md)<!-- -->. |
+|  [SavedObjectUnsanitizedDoc](./kibana-plugin-core-server.savedobjectunsanitizeddoc.md) | We want to have two types, one that guarantees a "references" attribute will exist and one that allows it to be null. Since we're not migrating all the saved objects to have a "references" array, we need to support the scenarios where it may be missing (ex migrations). |
 |  [ScopeableRequest](./kibana-plugin-core-server.scopeablerequest.md) | A user credentials container. It accommodates the necessary auth credentials to impersonate the current user.<!-- -->See [KibanaRequest](./kibana-plugin-core-server.kibanarequest.md)<!-- -->. |
 |  [ServiceStatusLevel](./kibana-plugin-core-server.servicestatuslevel.md) | A convenience type that represents the union of each value in [ServiceStatusLevels](./kibana-plugin-core-server.servicestatuslevels.md)<!-- -->. |
 |  [SharedGlobalConfig](./kibana-plugin-core-server.sharedglobalconfig.md) |  |
diff --git a/docs/development/core/server/kibana-plugin-core-server.savedobjectmigrationfn.md b/docs/development/core/server/kibana-plugin-core-server.savedobjectmigrationfn.md
index a502c40db0cd8c..ef20f81d6ae308 100644
--- a/docs/development/core/server/kibana-plugin-core-server.savedobjectmigrationfn.md
+++ b/docs/development/core/server/kibana-plugin-core-server.savedobjectmigrationfn.md
@@ -9,7 +9,7 @@ A migration function for a [saved object type](./kibana-plugin-core-server.saved
 <b>Signature:</b>
 
 ```typescript
-export declare type SavedObjectMigrationFn = (doc: SavedObjectUnsanitizedDoc, context: SavedObjectMigrationContext) => SavedObjectUnsanitizedDoc;
+export declare type SavedObjectMigrationFn<TInputDoc extends SavedObjectUnsanitizedDoc | SavedObjectSanitizedDoc = SavedObjectUnsanitizedDoc, TOutputDoc extends SavedObjectUnsanitizedDoc | SavedObjectSanitizedDoc = SavedObjectUnsanitizedDoc> = (doc: TInputDoc, context: SavedObjectMigrationContext) => TOutputDoc;
 ```
 
 ## Example
diff --git a/docs/development/core/server/kibana-plugin-core-server.savedobjectunsanitizeddoc.md b/docs/development/core/server/kibana-plugin-core-server.savedobjectunsanitizeddoc.md
new file mode 100644
index 00000000000000..fe4eaecd003d09
--- /dev/null
+++ b/docs/development/core/server/kibana-plugin-core-server.savedobjectunsanitizeddoc.md
@@ -0,0 +1,13 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [kibana-plugin-core-server](./kibana-plugin-core-server.md) &gt; [SavedObjectUnsanitizedDoc](./kibana-plugin-core-server.savedobjectunsanitizeddoc.md)
+
+## SavedObjectUnsanitizedDoc type
+
+We want to have two types, one that guarantees a "references" attribute will exist and one that allows it to be null. Since we're not migrating all the saved objects to have a "references" array, we need to support the scenarios where it may be missing (ex migrations).
+
+<b>Signature:</b>
+
+```typescript
+export declare type SavedObjectUnsanitizedDoc = SavedObjectDoc & Partial<Referencable>;
+```
diff --git a/src/core/server/server.api.md b/src/core/server/server.api.md
index 6369720ada2c35..7dda1a1b3bfabd 100644
--- a/src/core/server/server.api.md
+++ b/src/core/server/server.api.md
@@ -1680,7 +1680,7 @@ export interface SavedObjectMigrationContext {
 }
 
 // @public
-export type SavedObjectMigrationFn = (doc: SavedObjectUnsanitizedDoc, context: SavedObjectMigrationContext) => SavedObjectUnsanitizedDoc;
+export type SavedObjectMigrationFn<TInputDoc extends SavedObjectUnsanitizedDoc | SavedObjectSanitizedDoc = SavedObjectUnsanitizedDoc, TOutputDoc extends SavedObjectUnsanitizedDoc | SavedObjectSanitizedDoc = SavedObjectUnsanitizedDoc> = (doc: TInputDoc, context: SavedObjectMigrationContext) => TOutputDoc;
 
 // @public
 export interface SavedObjectMigrationMap {