diff --git a/packages/binding-coap/src/coap-server.ts b/packages/binding-coap/src/coap-server.ts
index b94d91a9f..a570f66f2 100644
--- a/packages/binding-coap/src/coap-server.ts
+++ b/packages/binding-coap/src/coap-server.ts
@@ -35,7 +35,7 @@ import { MdnsIntroducer } from "./mdns-introducer";
 import { PropertyElement, DataSchema, ActionElement, EventElement } from "wot-thing-description-types";
 import { CoapServerConfig } from "./coap";
 import { DataSchemaValue } from "wot-typescript-definitions";
-import { filterPropertyObserveOperations, getPropertyOpValues } from "./util";
+import { getPropertyOpValues } from "./util";
 
 const { debug, warn, info, error } = createLoggers("binding-coap", "coap-server");
 
@@ -248,14 +248,6 @@ export default class CoapServer implements ProtocolServer {
                     continue;
                 }
 
-                let subprotocol: string | undefined;
-
-                const observeOpValues = filterPropertyObserveOperations(formOpValues);
-
-                if (observeOpValues.length > 0) {
-                    subprotocol = "cov:observe";
-                }
-
                 const form = this.createAffordanceForm(
                     base,
                     this.PROPERTY_DIR,
@@ -263,8 +255,7 @@ export default class CoapServer implements ProtocolServer {
                     formOpValues,
                     thing.uriVariables,
                     propertyName,
-                    property.uriVariables,
-                    subprotocol
+                    property.uriVariables
                 );
 
                 this.addFormToAffordance(form, property);
@@ -299,8 +290,7 @@ export default class CoapServer implements ProtocolServer {
                 ["subscribeevent", "unsubscribeevent"],
                 thing.uriVariables,
                 eventName,
-                event.uriVariables,
-                "cov:observe"
+                event.uriVariables
             );
 
             this.addFormToAffordance(form, event);
diff --git a/packages/binding-coap/src/util.ts b/packages/binding-coap/src/util.ts
index cf4f4529e..e0ad034b9 100644
--- a/packages/binding-coap/src/util.ts
+++ b/packages/binding-coap/src/util.ts
@@ -60,11 +60,10 @@ export function filterEventOperations(opValues: string[]) {
 /**
  * Function to (potentially) generate two arrays of `op` values: One with the
  * values "readproperty" and "writeproperty", and one with
- * "observerproperty" and "unobserveproperty".
+ * "observeproperty" and "unobserveproperty".
  *
- * This CoAP-specific distinction is made to be able to generate
- * separate forms for the observe-related operations, where the addition
- * of a `subprotocol` field with a value of `cov:observe` has to be added.
+ * This distinction is made to be able to generate separate forms for the
+ * observe-related operations.
  *
  * @param property The property for which the forms are going to be
  *                 generated.
diff --git a/packages/binding-coap/test/coap-server-test.ts b/packages/binding-coap/test/coap-server-test.ts
index dc91d4da7..a947cfff1 100644
--- a/packages/binding-coap/test/coap-server-test.ts
+++ b/packages/binding-coap/test/coap-server-test.ts
@@ -635,7 +635,7 @@ class CoapServerTest {
         await coapServer.stop();
     }
 
-    @test async "should add the cov:observe subprotocol value to observable properties and events "() {
+    @test async "should add the correct operation types to observable properties and events "() {
         const coapServer = new CoapServer({ port: 5683 });
         const servient = new Servient();
         servient.addServer(coapServer);
@@ -679,7 +679,6 @@ class CoapServerTest {
 
                         if (observeOpValuePresent) {
                             observeOpValueFormCount++;
-                            expect(form.subprotocol).to.eql("cov:observe");
                         }
 
                         const readWriteOpValueCount = filterPropertyReadWriteOperations(
@@ -703,14 +702,17 @@ class CoapServerTest {
                 for (const event of Object.values(td.events!)) {
                     for (const form of event.forms) {
                         const opValues = form.op!;
-                        expect(opValues.length > 0);
+                        // eslint-disable-next-line no-unused-expressions
+                        expect(opValues.length > 0).to.be.true;
 
                         const eventOpValueCount = filterEventOperations(opValues as Array<string>).length;
                         const eventOpValueCountPresent = eventOpValueCount > 0;
 
-                        expect(eventOpValueCountPresent);
+                        // eslint-disable-next-line no-unused-expressions
+                        expect(eventOpValueCountPresent).to.be.true;
 
-                        expect(form.subprotocol === "cov:observe");
+                        // eslint-disable-next-line no-unused-expressions
+                        expect(form.subprotocol === "cov:observe").to.be.false;
                     }
                 }