diff --git a/lwm2m/transformShadowUpdateToLwM2M.spec.ts b/lwm2m/transformShadowUpdateToLwM2M.spec.ts
index 4de106e..9121e69 100644
--- a/lwm2m/transformShadowUpdateToLwM2M.spec.ts
+++ b/lwm2m/transformShadowUpdateToLwM2M.spec.ts
@@ -16,13 +16,30 @@ void describe('transformShadowUpdateToLwM2M()', () => {
 							ts: 1699202473044,
 						},
 						bat: { v: 4382, ts: 1699202473174 },
+						fg: {
+							ts: 1708942457126,
+							v: {
+								V: 3710,
+								SoC: 20,
+								I: -442,
+								T: 297,
+							},
+						},
 					},
 				},
 			}),
 			[
 				{
 					ObjectID: 14202,
-					Resources: { '1': 4.382, '99': new Date('2023-11-05T16:41:13.174Z') },
+					Resources: {
+						'0': null,
+						'1': 4.382,
+						'2': null,
+						'3': null,
+						'4': null,
+						'5': null,
+						'99': new Date('2023-11-05T16:41:13.174Z'),
+					},
 				},
 				{
 					ObjectID: 14205,
@@ -30,9 +47,23 @@ void describe('transformShadowUpdateToLwM2M()', () => {
 						'0': 27.07,
 						'1': 29.261,
 						'2': 97.13,
+						'10': null,
 						'99': new Date('2023-11-05T16:41:13.044Z'),
 					},
 				},
+				// Make sure optional resources are unset
+				{
+					ObjectID: 14202,
+					Resources: {
+						'0': 20,
+						'1': 3.71,
+						'2': -442,
+						'3': 29.7,
+						'4': null,
+						'5': null,
+						'99': new Date(1708942457126),
+					},
+				},
 			],
 		))
 })
diff --git a/lwm2m/transformShadowUpdateToLwM2M.ts b/lwm2m/transformShadowUpdateToLwM2M.ts
index 6432184..20c5c39 100644
--- a/lwm2m/transformShadowUpdateToLwM2M.ts
+++ b/lwm2m/transformShadowUpdateToLwM2M.ts
@@ -3,6 +3,7 @@ import {
 	senMLtoLwM2M,
 	type LwM2MObjectInstance,
 	type Transformer,
+	definitions,
 } from '@hello.nrfcloud.com/proto-lwm2m'
 
 type Update = {
@@ -90,6 +91,25 @@ export const transformShadowUpdateToLwM2M = (
 			.then((result) => result.filter((item) => item !== null))
 			// Convert it to LwM2M
 			.then(senMLtoLwM2M)
+			// Mark omitted properties as unset
+			.then((lwm2m) => {
+				return lwm2m.map((o) => {
+					const res = definitions[o.ObjectID]?.Resources ?? {}
+					const resourcesInObject = Object.keys(o.Resources)
+					return Object.keys(res)
+						.filter((r) => !resourcesInObject.includes(r))
+						.reduce<LwM2MObjectInstance>(
+							(o, undefinedResourceID) => ({
+								...o,
+								Resources: {
+									...o.Resources,
+									[undefinedResourceID]: null,
+								},
+							}),
+							o,
+						)
+				})
+			})
 			// Handle errors
 			.catch((err) => {
 				console.error(err)
diff --git a/package-lock.json b/package-lock.json
index 054c9bd..1a832d5 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -10,7 +10,7 @@
       "license": "BSD-3-Clause",
       "dependencies": {
         "@aws-sdk/client-s3": "3.521.0",
-        "@hello.nrfcloud.com/proto-lwm2m": "2.4.6",
+        "@hello.nrfcloud.com/proto-lwm2m": "2.5.1",
         "@nordicsemiconductor/from-env": "3.0.1",
         "@nordicsemiconductor/timestream-helpers": "6.0.2",
         "@protobuf-ts/runtime": "2.9.3",
@@ -3487,9 +3487,9 @@
       }
     },
     "node_modules/@hello.nrfcloud.com/proto-lwm2m": {
-      "version": "2.4.6",
-      "resolved": "https://registry.npmjs.org/@hello.nrfcloud.com/proto-lwm2m/-/proto-lwm2m-2.4.6.tgz",
-      "integrity": "sha512-94Ob8jMMwbAqJQC3umXpNSJP5PhUcik10QnCXugjofWvkdL1ICL2FurD5/JavgELG8649/HSpykCbz9Sp4Fxaw==",
+      "version": "2.5.1",
+      "resolved": "https://registry.npmjs.org/@hello.nrfcloud.com/proto-lwm2m/-/proto-lwm2m-2.5.1.tgz",
+      "integrity": "sha512-7kZUnidLgXCp0lZZN7xSaYbjueFFWcy7AjdInWbJK958iCBxZCq121n51w6bqmEczR6f+xUmUv6uVmQaGArTxQ==",
       "dependencies": {
         "@sinclair/typebox": "0.32.14",
         "ajv": "8.12.0",
diff --git a/package.json b/package.json
index 5b3a48f..7be89c4 100644
--- a/package.json
+++ b/package.json
@@ -82,7 +82,7 @@
   "prettier": "@bifravst/prettier-config",
   "dependencies": {
     "@aws-sdk/client-s3": "3.521.0",
-    "@hello.nrfcloud.com/proto-lwm2m": "2.4.6",
+    "@hello.nrfcloud.com/proto-lwm2m": "2.5.1",
     "@nordicsemiconductor/from-env": "3.0.1",
     "@nordicsemiconductor/timestream-helpers": "6.0.2",
     "@protobuf-ts/runtime": "2.9.3",