diff --git a/src/controllers/api/missionInventoryUpdateController.ts b/src/controllers/api/missionInventoryUpdateController.ts
index 49eb6e1b..153ebcee 100644
--- a/src/controllers/api/missionInventoryUpdateController.ts
+++ b/src/controllers/api/missionInventoryUpdateController.ts
@@ -98,8 +98,14 @@ export const missionInventoryUpdateController: RequestHandler = async (req, res)
     const inventoryResponse = await getInventoryResponse(inventory, true, account.BuildLabel);
 
     //TODO: figure out when to send inventory. it is needed for many cases.
+    if (missionReport.RJ) {
+        logger.debug(`railjack interstitial request, sending only deltas`, {
+            InventoryChanges: inventoryChanges,
+            AffiliationMods
+        });
+    }
     res.json({
-        InventoryJson: JSON.stringify(inventoryResponse),
+        InventoryJson: missionReport.RJ ? undefined : JSON.stringify(inventoryResponse),
         InventoryChanges: inventoryChanges,
         MissionRewards,
         ...credits,
diff --git a/src/types/requestTypes.ts b/src/types/requestTypes.ts
index c9292fc4..51445b1e 100644
--- a/src/types/requestTypes.ts
+++ b/src/types/requestTypes.ts
@@ -148,6 +148,7 @@ export type IMissionInventoryUpdateRequest = {
         MultiProgress: unknown[];
     }[];
     InvasionProgress?: IInvasionProgressClient[];
+    RJ?: boolean;
     ConquestMissionsCompleted?: number;
     duviriSuitSelection?: string;
     duviriPistolSelection?: string;