diff --git a/shared/src/main/java/com/google/samples/apps/iosched/shared/result/Event.kt b/shared/src/main/java/com/google/samples/apps/iosched/shared/result/Event.kt
index 427915348e..685a3d5be9 100644
--- a/shared/src/main/java/com/google/samples/apps/iosched/shared/result/Event.kt
+++ b/shared/src/main/java/com/google/samples/apps/iosched/shared/result/Event.kt
@@ -21,7 +21,7 @@ import androidx.lifecycle.Observer
 /**
  * Used as a wrapper for data that is exposed via a LiveData that represents an event.
  */
-open class Event<out T>(private val content: T) {
+open class Event<out T : Any>(private val content: T) {
 
     var hasBeenHandled = false
         private set // Allow external read but not write
@@ -50,7 +50,7 @@ open class Event<out T>(private val content: T) {
  *
  * [onEventUnhandledContent] is *only* called if the [Event]'s contents has not been handled.
  */
-class EventObserver<T>(private val onEventUnhandledContent: (T) -> Unit) : Observer<Event<T>> {
+class EventObserver<T : Any>(private val onEventUnhandledContent: (T) -> Unit) : Observer<Event<T>> {
     override fun onChanged(event: Event<T>?) {
         event?.getContentIfNotHandled()?.let { value ->
             onEventUnhandledContent(value)