diff --git a/src/test/java/nl/contezza/drc/tests/custom/CustomUpdateIOT.java b/src/test/java/nl/contezza/drc/tests/custom/CustomUpdateIOT.java
new file mode 100644
index 0000000..347f29c
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+++ b/src/test/java/nl/contezza/drc/tests/custom/CustomUpdateIOT.java
@@ -0,0 +1,67 @@
+package nl.contezza.drc.tests.custom;
+
+import org.json.JSONObject;
+import org.testng.Assert;
+import org.testng.annotations.BeforeTest;
+import org.testng.annotations.Test;
+
+import io.restassured.path.json.JsonPath;
+import io.restassured.response.Response;
+import nl.contezza.drc.rest.RestTest;
+import nl.contezza.drc.service.EIOService;
+import nl.contezza.drc.service.ZTCService;
+
+/**
+ * Some custom unit tests which are not mapped to any python scripts.
+ */
+
+// @Log4j2
+public class CustomUpdateIOT extends RestTest {
+
+	private String informatieobjecttypeUrl2 = null;
+
+	/**
+	 * Create necessary dependencies.
+	 */
+	@BeforeTest(groups = "CustomUpdateIOT")
+	public void init() {
+		// Create random catalogi
+		ZTCService ztcService = new ZTCService();
+		JsonPath json = new JsonPath(ztcService.createCatalogus().asString());
+
+		// Create informatieobjecttype
+		String catalogusUrl = json.getString("url").replace(ZTC_BASE_URI, ZTC_DOCKER_URI);
+		json = new JsonPath(ztcService.createInformatieObjectType(catalogusUrl).asString());
+		informatieobjecttypeUrl = json.getString("url").replace(ZTC_BASE_URI, ZTC_DOCKER_URI);
+
+		// Create informatieobjecttype 2
+		json = new JsonPath(ztcService.createInformatieObjectType(catalogusUrl).asString());
+		informatieobjecttypeUrl2 = json.getString("url").replace(ZTC_BASE_URI, ZTC_DOCKER_URI);
+
+		Response res = ztcService.publishInformatieObjectType(
+				informatieobjecttypeUrl.substring(informatieobjecttypeUrl.lastIndexOf('/') + 1).trim());
+		Assert.assertEquals(res.getStatusCode(), 200);
+
+		res = ztcService.publishInformatieObjectType(
+				informatieobjecttypeUrl2.substring(informatieobjecttypeUrl2.lastIndexOf('/') + 1).trim());
+		Assert.assertEquals(res.getStatusCode(), 200);
+	}
+
+	@Test(groups = "CustomUpdateIOT")
+	public void test_update_IOT() {
+		EIOService eioService = new EIOService();
+
+		// Create EIO
+		String eioUrl = new JsonPath(eioService.testCreate(informatieobjecttypeUrl).asString()).getString("url");
+
+		// Do lock
+		JsonPath json = new JsonPath(eioService.lock(eioUrl).asString());
+
+		JSONObject body = new JSONObject();
+		body.put("informatieobjecttype", informatieobjecttypeUrl2);
+		body.put("lock", json.getString("lock"));
+
+		Response res = eioService.partialUpdate(eioUrl, body);
+		Assert.assertEquals(res.getStatusCode(), 200);
+	}
+}
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