diff --git a/src/services/inventoryService.ts b/src/services/inventoryService.ts
index e62e51b9..9f9e7327 100644
--- a/src/services/inventoryService.ts
+++ b/src/services/inventoryService.ts
@@ -308,8 +308,8 @@ export const addItem = async (
             };
         } else if (ExportResources[typeName].productCategory == "KubrowPetEggs") {
             const changes: IKubrowPetEggClient[] = [];
-            if (quantity < 0) {
-                throw new Error(`removal of KubrowPetEggs not handled`);
+            if (quantity < 0 || quantity > 100) {
+                throw new Error(`unexpected acquisition quantity of KubrowPetEggs: ${quantity}`);
             }
             for (let i = 0; i != quantity; ++i) {
                 const egg: IKubrowPetEggDatabase = {