diff --git a/.scalafix.conf b/.scalafix.conf
index 90d9a78ca1..e7e05d6f75 100644
--- a/.scalafix.conf
+++ b/.scalafix.conf
@@ -2,6 +2,7 @@
 rules = [
   RemoveUnused
   "github:ohze/scalafix-rules/ConstructorProcedureSyntax"
+  "github:ohze/scalafix-rules/FinalObject"
 ]
 RemoveUnused.imports = true
 RemoveUnused.privates = false
diff --git a/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/Effect.scala b/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/Effect.scala
index f30885ad70..9c68fa826c 100644
--- a/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/Effect.scala
+++ b/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/Effect.scala
@@ -191,7 +191,7 @@ object Effect {
     def duration(): java.time.Duration = d.asJava
   }
 
-  final case object ReceiveTimeoutCancelled extends ReceiveTimeoutCancelled
+  case object ReceiveTimeoutCancelled extends ReceiveTimeoutCancelled
 
   sealed abstract class ReceiveTimeoutCancelled extends Effect
 
diff --git a/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/internal/TestKitUtils.scala b/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/internal/TestKitUtils.scala
index 37f190a453..5112361488 100644
--- a/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/internal/TestKitUtils.scala
+++ b/akka-actor-testkit-typed/src/main/scala/akka/actor/testkit/typed/internal/TestKitUtils.scala
@@ -30,7 +30,7 @@ private[akka] object ActorTestKitGuardian {
   final case class StopActor[T](ref: ActorRef[T], replyTo: ActorRef[Ack.type]) extends TestKitCommand
   final case class ActorStopped[T](replyTo: ActorRef[Ack.type]) extends TestKitCommand
 
-  final case object Ack
+  case object Ack
 
   val testKitGuardian: Behavior[TestKitCommand] = Behaviors.receive[TestKitCommand] {
     case (context, SpawnActor(name, behavior, reply, props)) =>
diff --git a/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducer.scala b/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducer.scala
index 134e3c396b..9f0c1ab931 100644
--- a/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducer.scala
+++ b/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducer.scala
@@ -17,7 +17,7 @@ object TestProducer {
 
   trait Command
   final case class RequestNext(sendTo: ActorRef[TestConsumer.Job]) extends Command
-  private final case object Tick extends Command
+  private case object Tick extends Command
 
   val defaultProducerDelay: FiniteDuration = 20.millis
 
diff --git a/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducerWorkPulling.scala b/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducerWorkPulling.scala
index 80805ee054..7f9b36ce47 100644
--- a/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducerWorkPulling.scala
+++ b/akka-actor-typed-tests/src/test/scala/akka/actor/typed/delivery/TestProducerWorkPulling.scala
@@ -14,7 +14,7 @@ object TestProducerWorkPulling {
 
   trait Command
   final case class RequestNext(sendTo: ActorRef[TestConsumer.Job]) extends Command
-  private final case object Tick extends Command
+  private case object Tick extends Command
 
   def apply(
       delay: FiniteDuration,
diff --git a/akka-actor-typed/src/main/scala/akka/actor/typed/delivery/internal/ConsumerControllerImpl.scala b/akka-actor-typed/src/main/scala/akka/actor/typed/delivery/internal/ConsumerControllerImpl.scala
index 0ae382a660..01798cbc29 100644
--- a/akka-actor-typed/src/main/scala/akka/actor/typed/delivery/internal/ConsumerControllerImpl.scala
+++ b/akka-actor-typed/src/main/scala/akka/actor/typed/delivery/internal/ConsumerControllerImpl.scala
@@ -73,7 +73,7 @@ import akka.annotation.InternalApi
   /** For commands defined in public ConsumerController */
   trait UnsealedInternalCommand extends InternalCommand
 
-  private final case object Retry extends InternalCommand
+  private case object Retry extends InternalCommand
 
   private final case class ConsumerTerminated(consumer: ActorRef[_]) extends InternalCommand
 
diff --git a/akka-actor/src/main/scala/akka/io/dns/DnsProtocol.scala b/akka-actor/src/main/scala/akka/io/dns/DnsProtocol.scala
index 85ed71b567..77eed4cb55 100644
--- a/akka-actor/src/main/scala/akka/io/dns/DnsProtocol.scala
+++ b/akka-actor/src/main/scala/akka/io/dns/DnsProtocol.scala
@@ -30,7 +30,7 @@ object DnsProtocol {
 
   sealed trait RequestType
   final case class Ip(ipv4: Boolean = true, ipv6: Boolean = true) extends RequestType
-  final case object Srv extends RequestType
+  case object Srv extends RequestType
 
   /**
    * Java API
diff --git a/akka-actor/src/main/scala/akka/pattern/Backoff.scala b/akka-actor/src/main/scala/akka/pattern/Backoff.scala
index 5dadaa5674..d72ee54d60 100644
--- a/akka-actor/src/main/scala/akka/pattern/Backoff.scala
+++ b/akka-actor/src/main/scala/akka/pattern/Backoff.scala
@@ -635,5 +635,5 @@ private final case class BackoffOptionsImpl(
 }
 
 private sealed trait BackoffType
-private final case object StopImpliesFailure extends BackoffType
-private final case object RestartImpliesFailure extends BackoffType
+private case object StopImpliesFailure extends BackoffType
+private case object RestartImpliesFailure extends BackoffType
diff --git a/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala b/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala
index 9d36ed4f7a..bb37037a2f 100644
--- a/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala
+++ b/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala
@@ -424,5 +424,5 @@ private final case class BackoffOnFailureOptionsImpl[T](
 }
 
 private[akka] sealed trait BackoffReset
-private[akka] final case object ManualReset extends BackoffReset
+private[akka] case object ManualReset extends BackoffReset
 private[akka] final case class AutoReset(resetBackoff: FiniteDuration) extends BackoffReset
diff --git a/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala b/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala
index 7ec00f1696..3670b50b00 100644
--- a/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala
+++ b/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala
@@ -246,7 +246,7 @@ object BackoffSupervisor {
    * Send this message to the `BackoffSupervisor` and it will reply with
    * [[BackoffSupervisor.CurrentChild]] containing the `ActorRef` of the current child, if any.
    */
-  final case object GetCurrentChild
+  case object GetCurrentChild
 
   /**
    * Java API: Send this message to the `BackoffSupervisor` and it will reply with
@@ -270,7 +270,7 @@ object BackoffSupervisor {
    * Send this message to the `BackoffSupervisor` and it will reset the back-off.
    * This should be used in conjunction with `withManualReset` in [[BackoffOptions]].
    */
-  final case object Reset
+  case object Reset
 
   /**
    * Java API: Send this message to the `BackoffSupervisor` and it will reset the back-off.
@@ -282,7 +282,7 @@ object BackoffSupervisor {
    * Send this message to the `BackoffSupervisor` and it will reply with
    * [[BackoffSupervisor.RestartCount]] containing the current restart count.
    */
-  final case object GetRestartCount
+  case object GetRestartCount
 
   /**
    * Java API: Send this message to the `BackoffSupervisor` and it will reply with
diff --git a/akka-bench-jmh/src/main/scala/akka/actor/typed/TypedBenchmarkActors.scala b/akka-bench-jmh/src/main/scala/akka/actor/typed/TypedBenchmarkActors.scala
index c00c5594c2..5233891baf 100644
--- a/akka-bench-jmh/src/main/scala/akka/actor/typed/TypedBenchmarkActors.scala
+++ b/akka-bench-jmh/src/main/scala/akka/actor/typed/TypedBenchmarkActors.scala
@@ -16,7 +16,7 @@ object TypedBenchmarkActors {
 
   // to avoid benchmark to be dominated by allocations of message
   // we pass the respondTo actor ref into the behavior
-  final case object Message
+  case object Message
 
   private def echoBehavior(respondTo: ActorRef[Message.type]): Behavior[Message.type] = Behaviors.receive { (_, _) =>
     respondTo ! Message
diff --git a/akka-cluster-sharding-typed/src/main/scala/akka/cluster/sharding/typed/ClusterShardingSettings.scala b/akka-cluster-sharding-typed/src/main/scala/akka/cluster/sharding/typed/ClusterShardingSettings.scala
index 4c71b3a51d..ea1173a118 100644
--- a/akka-cluster-sharding-typed/src/main/scala/akka/cluster/sharding/typed/ClusterShardingSettings.scala
+++ b/akka-cluster-sharding-typed/src/main/scala/akka/cluster/sharding/typed/ClusterShardingSettings.scala
@@ -104,8 +104,8 @@ object ClusterShardingSettings {
       else
         throw new IllegalArgumentException("Not recognized StateStoreMode, only 'ddata' is supported.")
   }
-  final case object StateStoreModePersistence extends StateStoreMode { override def name = "persistence" }
-  final case object StateStoreModeDData extends StateStoreMode { override def name = "ddata" }
+  case object StateStoreModePersistence extends StateStoreMode { override def name = "persistence" }
+  case object StateStoreModeDData extends StateStoreMode { override def name = "ddata" }
 
   // generated using kaze-class
   final class TuningParameters private (
diff --git a/akka-cluster-sharding-typed/src/test/scala/akka/cluster/sharding/typed/delivery/ReliableDeliveryShardingSpec.scala b/akka-cluster-sharding-typed/src/test/scala/akka/cluster/sharding/typed/delivery/ReliableDeliveryShardingSpec.scala
index 09374f0b39..554707f1bc 100644
--- a/akka-cluster-sharding-typed/src/test/scala/akka/cluster/sharding/typed/delivery/ReliableDeliveryShardingSpec.scala
+++ b/akka-cluster-sharding-typed/src/test/scala/akka/cluster/sharding/typed/delivery/ReliableDeliveryShardingSpec.scala
@@ -42,7 +42,7 @@ object ReliableDeliveryShardingSpec {
     trait Command
     final case class RequestNext(sendToRef: ActorRef[ShardingEnvelope[TestConsumer.Job]]) extends Command
 
-    private final case object Tick extends Command
+    private case object Tick extends Command
 
     def apply(producerController: ActorRef[ShardingProducerController.Start[TestConsumer.Job]]): Behavior[Command] = {
       Behaviors.setup { context =>
diff --git a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/Shard.scala b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/Shard.scala
index 9ab9d50e29..7be3ba6e63 100644
--- a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/Shard.scala
+++ b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/Shard.scala
@@ -96,7 +96,7 @@ private[akka] object Shard {
   final case class LeaseAcquireResult(acquired: Boolean, reason: Option[Throwable]) extends DeadLetterSuppression
   final case class LeaseLost(reason: Option[Throwable]) extends DeadLetterSuppression
 
-  final case object LeaseRetry extends DeadLetterSuppression
+  case object LeaseRetry extends DeadLetterSuppression
   private val LeaseRetryTimer = "lease-retry"
 
   object State {
diff --git a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardRegion.scala b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardRegion.scala
index 8756aa27af..dac4acc2d3 100644
--- a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardRegion.scala
+++ b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardRegion.scala
@@ -203,7 +203,7 @@ object ShardRegion {
    * the `ShardRegion` and then the `ShardRegion` actor will be stopped. You can `watch`
    * it to know when it is completed.
    */
-  @SerialVersionUID(1L) final case object GracefulShutdown extends ShardRegionCommand
+  @SerialVersionUID(1L) case object GracefulShutdown extends ShardRegionCommand
 
   /**
    * We must be sure that a shard is initialized before to start send messages to it.
@@ -226,7 +226,7 @@ object ShardRegion {
    * Intended for testing purpose to see when cluster sharding is "ready" or to monitor
    * the state of the shard regions.
    */
-  @SerialVersionUID(1L) final case object GetCurrentRegions extends ShardRegionQuery with ClusterShardingSerializable
+  @SerialVersionUID(1L) case object GetCurrentRegions extends ShardRegionQuery with ClusterShardingSerializable
 
   /**
    * Java API:
diff --git a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/external/ExternalShardAllocationStrategy.scala b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/external/ExternalShardAllocationStrategy.scala
index 385a6631b1..893b4d5660 100644
--- a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/external/ExternalShardAllocationStrategy.scala
+++ b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/external/ExternalShardAllocationStrategy.scala
@@ -36,7 +36,7 @@ object ExternalShardAllocationStrategy {
 
   // local only messages
   private[akka] final case class GetShardLocation(shard: ShardId)
-  private[akka] final case object GetShardLocations
+  private[akka] case object GetShardLocations
   private[akka] final case class GetShardLocationsResponse(desiredAllocations: Map[ShardId, Address])
   private[akka] final case class GetShardLocationResponse(address: Option[Address])
 
diff --git a/akka-cluster-tools/src/main/scala/akka/cluster/singleton/ClusterSingletonManager.scala b/akka-cluster-tools/src/main/scala/akka/cluster/singleton/ClusterSingletonManager.scala
index 2c484019ae..68499c3d0f 100644
--- a/akka-cluster-tools/src/main/scala/akka/cluster/singleton/ClusterSingletonManager.scala
+++ b/akka-cluster-tools/src/main/scala/akka/cluster/singleton/ClusterSingletonManager.scala
@@ -217,7 +217,7 @@ object ClusterSingletonManager {
 
     final case class HandOverRetry(count: Int)
     final case class TakeOverRetry(count: Int)
-    final case object LeaseRetry
+    case object LeaseRetry
     case object Cleanup
     case object StartOldestChangedBuffer
 
diff --git a/akka-cluster-tools/src/multi-jvm/scala/akka/cluster/TestLeaseActor.scala b/akka-cluster-tools/src/multi-jvm/scala/akka/cluster/TestLeaseActor.scala
index 76eacbd6a2..54d03ba74c 100644
--- a/akka-cluster-tools/src/multi-jvm/scala/akka/cluster/TestLeaseActor.scala
+++ b/akka-cluster-tools/src/multi-jvm/scala/akka/cluster/TestLeaseActor.scala
@@ -35,7 +35,7 @@ object TestLeaseActor {
   final case class Release(owner: String) extends LeaseRequest
   final case class Create(leaseName: String, ownerName: String) extends JavaSerializable
 
-  final case object GetRequests extends JavaSerializable
+  case object GetRequests extends JavaSerializable
   final case class LeaseRequests(requests: List[LeaseRequest]) extends JavaSerializable
   final case class ActionRequest(request: LeaseRequest, result: Any) extends JavaSerializable // boolean of Failure
 }
diff --git a/akka-cluster/src/main/scala/akka/cluster/ClusterDaemon.scala b/akka-cluster/src/main/scala/akka/cluster/ClusterDaemon.scala
index d51a1235a4..5f9f4abef8 100644
--- a/akka-cluster/src/main/scala/akka/cluster/ClusterDaemon.scala
+++ b/akka-cluster/src/main/scala/akka/cluster/ClusterDaemon.scala
@@ -177,7 +177,7 @@ private[cluster] object InternalClusterAction {
   final case class PublishChanges(state: MembershipState) extends PublishMessage
   final case class PublishEvent(event: ClusterDomainEvent) extends PublishMessage
 
-  final case object ExitingCompleted
+  case object ExitingCompleted
 
 }
 
diff --git a/akka-cluster/src/main/scala/akka/cluster/ClusterEvent.scala b/akka-cluster/src/main/scala/akka/cluster/ClusterEvent.scala
index 1381970088..0fe6a21710 100644
--- a/akka-cluster/src/main/scala/akka/cluster/ClusterEvent.scala
+++ b/akka-cluster/src/main/scala/akka/cluster/ClusterEvent.scala
@@ -337,7 +337,7 @@ object ClusterEvent {
    * This event is published when the cluster node is shutting down,
    * before the final [[MemberRemoved]] events are published.
    */
-  final case object ClusterShuttingDown extends ClusterDomainEvent
+  case object ClusterShuttingDown extends ClusterDomainEvent
 
   /**
    * Java API: get the singleton instance of `ClusterShuttingDown` event
diff --git a/akka-distributed-data/src/main/scala/akka/cluster/ddata/Replicator.scala b/akka-distributed-data/src/main/scala/akka/cluster/ddata/Replicator.scala
index ee5376e0d4..7043cc1ddc 100644
--- a/akka-distributed-data/src/main/scala/akka/cluster/ddata/Replicator.scala
+++ b/akka-distributed-data/src/main/scala/akka/cluster/ddata/Replicator.scala
@@ -781,7 +781,7 @@ object Replicator {
    * Get current number of replicas, including the local replica.
    * Will reply to sender with [[ReplicaCount]].
    */
-  final case object GetReplicaCount
+  case object GetReplicaCount
 
   /**
    * Java API: The `GetReplicaCount` instance
diff --git a/akka-persistence-query/src/main/scala/akka/persistence/query/Offset.scala b/akka-persistence-query/src/main/scala/akka/persistence/query/Offset.scala
index fc6fc57dd2..7d845fc5ec 100644
--- a/akka-persistence-query/src/main/scala/akka/persistence/query/Offset.scala
+++ b/akka-persistence-query/src/main/scala/akka/persistence/query/Offset.scala
@@ -52,7 +52,7 @@ final case class TimeBasedUUID(value: UUID) extends Offset with Ordered[TimeBase
 /**
  * Used when retrieving all events.
  */
-final case object NoOffset extends Offset {
+case object NoOffset extends Offset {
 
   /**
    * Java API:
diff --git a/akka-persistence-typed/src/test/scala/akka/persistence/typed/ClusterSingletonPersistenceSpec.scala b/akka-persistence-typed/src/test/scala/akka/persistence/typed/ClusterSingletonPersistenceSpec.scala
index fd5890c64a..3ad3ec629f 100644
--- a/akka-persistence-typed/src/test/scala/akka/persistence/typed/ClusterSingletonPersistenceSpec.scala
+++ b/akka-persistence-typed/src/test/scala/akka/persistence/typed/ClusterSingletonPersistenceSpec.scala
@@ -32,7 +32,7 @@ object ClusterSingletonPersistenceSpec {
   sealed trait Command
   final case class Add(s: String) extends Command
   final case class Get(replyTo: ActorRef[String]) extends Command
-  private final case object StopPlz extends Command
+  private case object StopPlz extends Command
 
   val persistentActor: Behavior[Command] =
     EventSourcedBehavior[Command, String, String](
diff --git a/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorRetentionSpec.scala b/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorRetentionSpec.scala
index b0ada72fc7..99b6fe16fb 100644
--- a/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorRetentionSpec.scala
+++ b/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorRetentionSpec.scala
@@ -44,10 +44,10 @@ object EventSourcedBehaviorRetentionSpec extends Matchers {
     """)
 
   sealed trait Command extends CborSerializable
-  final case object Increment extends Command
+  case object Increment extends Command
   final case class IncrementWithPersistAll(nr: Int) extends Command
   final case class GetValue(replyTo: ActorRef[State]) extends Command
-  final case object StopIt extends Command
+  case object StopIt extends Command
 
   final case class WrappedSignal(signal: EventSourcedSignal)
 
diff --git a/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorSpec.scala b/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorSpec.scala
index 263c3d039d..9e63c07a05 100644
--- a/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorSpec.scala
+++ b/akka-persistence-typed/src/test/scala/akka/persistence/typed/scaladsl/EventSourcedBehaviorSpec.scala
@@ -91,22 +91,22 @@ object EventSourcedBehaviorSpec {
     """)
 
   sealed trait Command extends CborSerializable
-  final case object Increment extends Command
-  final case object IncrementThenLogThenStop extends Command
-  final case object IncrementTwiceThenLogThenStop extends Command
+  case object Increment extends Command
+  case object IncrementThenLogThenStop extends Command
+  case object IncrementTwiceThenLogThenStop extends Command
   final case class IncrementWithPersistAll(nr: Int) extends Command
-  final case object IncrementLater extends Command
-  final case object IncrementAfterReceiveTimeout extends Command
-  final case object IncrementTwiceAndThenLog extends Command
+  case object IncrementLater extends Command
+  case object IncrementAfterReceiveTimeout extends Command
+  case object IncrementTwiceAndThenLog extends Command
   final case class IncrementWithConfirmation(replyTo: ActorRef[Done]) extends Command
-  final case object DoNothingAndThenLog extends Command
-  final case object EmptyEventsListAndThenLog extends Command
+  case object DoNothingAndThenLog extends Command
+  case object EmptyEventsListAndThenLog extends Command
   final case class GetValue(replyTo: ActorRef[State]) extends Command
-  final case object DelayFinished extends Command
+  case object DelayFinished extends Command
   private case object Timeout extends Command
-  final case object LogThenStop extends Command
-  final case object Fail extends Command
-  final case object StopIt extends Command
+  case object LogThenStop extends Command
+  case object Fail extends Command
+  case object StopIt extends Command
 
   sealed trait Event extends CborSerializable
   final case class Incremented(delta: Int) extends Event
diff --git a/akka-persistence/src/main/scala/akka/persistence/journal/AsyncWriteProxy.scala b/akka-persistence/src/main/scala/akka/persistence/journal/AsyncWriteProxy.scala
index 42f2bdd06a..6327a29909 100644
--- a/akka-persistence/src/main/scala/akka/persistence/journal/AsyncWriteProxy.scala
+++ b/akka-persistence/src/main/scala/akka/persistence/journal/AsyncWriteProxy.scala
@@ -98,7 +98,7 @@ private[persistence] trait AsyncWriteProxy extends AsyncWriteJournal with Stash
  */
 private[persistence] object AsyncWriteProxy {
   final case class SetStore(ref: ActorRef)
-  final case object InitTimeout
+  case object InitTimeout
 }
 
 /**
diff --git a/akka-persistence/src/main/scala/akka/persistence/journal/EventAdapter.scala b/akka-persistence/src/main/scala/akka/persistence/journal/EventAdapter.scala
index 2134420873..6fcf4d45f6 100644
--- a/akka-persistence/src/main/scala/akka/persistence/journal/EventAdapter.scala
+++ b/akka-persistence/src/main/scala/akka/persistence/journal/EventAdapter.scala
@@ -105,14 +105,14 @@ final case class SingleEventSeq(event: Any) extends EventSeq { // TODO try to ma
 }
 
 sealed trait EmptyEventSeq extends EventSeq
-final object EmptyEventSeq extends EmptyEventSeq {
+object EmptyEventSeq extends EmptyEventSeq {
   override def events = Nil
 }
 
 final case class EventsSeq[E](events: immutable.Seq[E]) extends EventSeq
 
 /** No-op model adapter which passes through the incoming events as-is. */
-final case object IdentityEventAdapter extends EventAdapter {
+case object IdentityEventAdapter extends EventAdapter {
   override def toJournal(event: Any): Any = event
   override def fromJournal(event: Any, manifest: String): EventSeq = EventSeq.single(event)
   override def manifest(event: Any): String = ""
diff --git a/akka-persistence/src/main/scala/akka/persistence/journal/leveldb/LeveldbJournal.scala b/akka-persistence/src/main/scala/akka/persistence/journal/leveldb/LeveldbJournal.scala
index c0a2fe5b50..b6380262d7 100644
--- a/akka-persistence/src/main/scala/akka/persistence/journal/leveldb/LeveldbJournal.scala
+++ b/akka-persistence/src/main/scala/akka/persistence/journal/leveldb/LeveldbJournal.scala
@@ -92,7 +92,7 @@ private[persistence] object LeveldbJournal {
    * subscriber followed by [[PersistenceIdAdded]] messages when new persistenceIds
    * are created.
    */
-  final case object SubscribeAllPersistenceIds extends SubscriptionCommand
+  case object SubscribeAllPersistenceIds extends SubscriptionCommand
   final case class CurrentPersistenceIds(allPersistenceIds: Set[String]) extends DeadLetterSuppression
   final case class PersistenceIdAdded(persistenceId: String) extends DeadLetterSuppression
 
diff --git a/akka-persistence/src/test/scala/akka/persistence/OptimizedRecoverySpec.scala b/akka-persistence/src/test/scala/akka/persistence/OptimizedRecoverySpec.scala
index 1a7d0dc29d..a544427444 100644
--- a/akka-persistence/src/test/scala/akka/persistence/OptimizedRecoverySpec.scala
+++ b/akka-persistence/src/test/scala/akka/persistence/OptimizedRecoverySpec.scala
@@ -14,7 +14,7 @@ object OptimizedRecoverySpec {
     case object TakeSnapshot
     final case class Save(s: String)
     final case class Saved(s: String, seqNr: Long)
-    final case object PersistFromRecoveryCompleted
+    case object PersistFromRecoveryCompleted
 
     def props(name: String, recovery: Recovery, probe: ActorRef): Props = {
       Props(new TestPersistentActor(name, recovery, probe))
diff --git a/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/LatencySpec.scala b/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/LatencySpec.scala
index 548a283731..2c1e02b7af 100644
--- a/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/LatencySpec.scala
+++ b/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/LatencySpec.scala
@@ -63,7 +63,7 @@ object LatencySpec extends MultiNodeConfig {
        }
        """)).withFallback(RemotingMultiNodeSpec.commonConfig))
 
-  final case object Reset extends CborSerializable
+  case object Reset extends CborSerializable
 
   def echoProps(): Props =
     Props(new Echo).withDispatcher(Dispatchers.InternalDispatcherId)
diff --git a/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/MaxThroughputSpec.scala b/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/MaxThroughputSpec.scala
index 7d99753e89..68336309da 100644
--- a/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/MaxThroughputSpec.scala
+++ b/akka-remote-tests/src/multi-jvm/scala/akka/remote/artery/MaxThroughputSpec.scala
@@ -86,9 +86,9 @@ object MaxThroughputSpec extends MultiNodeConfig {
 
   case object Run
   sealed trait Echo extends DeadLetterSuppression with CborSerializable
-  final case object StartAck extends Echo
+  case object StartAck extends Echo
   final case class Start(correspondingReceiver: ActorRef) extends Echo
-  final case object End extends Echo
+  case object End extends Echo
   final case class Warmup(payload: AnyRef) extends CborSerializable
   final case class EndResult(totalReceived: Long) extends CborSerializable
   final case class FlowControl(id: Int, burstStartTime: Long) extends Echo
diff --git a/akka-stream-testkit/src/main/scala/akka/stream/testkit/StreamTestKit.scala b/akka-stream-testkit/src/main/scala/akka/stream/testkit/StreamTestKit.scala
index 327a504496..f11f71e3e7 100644
--- a/akka-stream-testkit/src/main/scala/akka/stream/testkit/StreamTestKit.scala
+++ b/akka-stream-testkit/src/main/scala/akka/stream/testkit/StreamTestKit.scala
@@ -35,7 +35,7 @@ object TestPublisher {
   final case class CancelSubscription(subscription: Subscription, cause: Throwable) extends PublisherEvent
   final case class RequestMore(subscription: Subscription, elements: Long) extends PublisherEvent
 
-  final object SubscriptionDone extends NoSerializationVerificationNeeded
+  object SubscriptionDone extends NoSerializationVerificationNeeded
 
   /**
    * Publisher that signals complete to subscribers, after handing a void subscription.
diff --git a/akka-stream/src/main/scala/akka/stream/Attributes.scala b/akka-stream/src/main/scala/akka/stream/Attributes.scala
index 3f8a3832a8..d977c648d0 100644
--- a/akka-stream/src/main/scala/akka/stream/Attributes.scala
+++ b/akka-stream/src/main/scala/akka/stream/Attributes.scala
@@ -310,7 +310,7 @@ object Attributes {
 
   final case class LogLevels(onElement: Logging.LogLevel, onFinish: Logging.LogLevel, onFailure: Logging.LogLevel)
       extends Attribute
-  final case object AsyncBoundary extends Attribute
+  case object AsyncBoundary extends Attribute
 
   /**
    * Cancellation strategies provide a way to configure the behavior of a stage when `cancelStage` is called.
diff --git a/akka-stream/src/main/scala/akka/stream/QueueOfferResult.scala b/akka-stream/src/main/scala/akka/stream/QueueOfferResult.scala
index 95ac081734..d4913f2db9 100644
--- a/akka-stream/src/main/scala/akka/stream/QueueOfferResult.scala
+++ b/akka-stream/src/main/scala/akka/stream/QueueOfferResult.scala
@@ -14,7 +14,7 @@ object QueueOfferResult {
   /**
    * Type is used to indicate that stream is successfully enqueued an element
    */
-  final case object Enqueued extends QueueOfferResult
+  case object Enqueued extends QueueOfferResult
 
   /**
    * Java API: The `Enqueued` singleton instance
@@ -24,7 +24,7 @@ object QueueOfferResult {
   /**
    * Type is used to indicate that stream is dropped an element
    */
-  final case object Dropped extends QueueOfferResult
+  case object Dropped extends QueueOfferResult
 
   /**
    * Java API: The `Dropped` singleton instance
diff --git a/akka-stream/src/main/scala/akka/stream/SubstreamCancelStrategy.scala b/akka-stream/src/main/scala/akka/stream/SubstreamCancelStrategy.scala
index c0587a5be4..701a66b083 100644
--- a/akka-stream/src/main/scala/akka/stream/SubstreamCancelStrategy.scala
+++ b/akka-stream/src/main/scala/akka/stream/SubstreamCancelStrategy.scala
@@ -16,12 +16,12 @@ private[akka] object SubstreamCancelStrategies {
   /**
    * INTERNAL API
    */
-  private[akka] final case object Propagate extends SubstreamCancelStrategy
+  private[akka] case object Propagate extends SubstreamCancelStrategy
 
   /**
    * INTERNAL API
    */
-  private[akka] final case object Drain extends SubstreamCancelStrategy
+  private[akka] case object Drain extends SubstreamCancelStrategy
 }
 
 object SubstreamCancelStrategy {
diff --git a/akka-stream/src/main/scala/akka/stream/impl/EmptySource.scala b/akka-stream/src/main/scala/akka/stream/impl/EmptySource.scala
index 1cfde5bf99..a40ec938d0 100644
--- a/akka-stream/src/main/scala/akka/stream/impl/EmptySource.scala
+++ b/akka-stream/src/main/scala/akka/stream/impl/EmptySource.scala
@@ -12,7 +12,7 @@ import akka.stream.stage._
 /**
  * INTERNAL API
  */
-@InternalApi private[akka] final object EmptySource extends GraphStage[SourceShape[Nothing]] {
+@InternalApi private[akka] object EmptySource extends GraphStage[SourceShape[Nothing]] {
   val out = Outlet[Nothing]("EmptySource.out")
   override val shape = SourceShape(out)
 
diff --git a/akka-stream/src/main/scala/akka/stream/impl/MaterializerGuardian.scala b/akka-stream/src/main/scala/akka/stream/impl/MaterializerGuardian.scala
index 0559ef2ab6..830786ed98 100644
--- a/akka-stream/src/main/scala/akka/stream/impl/MaterializerGuardian.scala
+++ b/akka-stream/src/main/scala/akka/stream/impl/MaterializerGuardian.scala
@@ -22,7 +22,7 @@ import scala.concurrent.Promise
 @InternalApi
 private[akka] object MaterializerGuardian {
 
-  final case object StartMaterializer
+  case object StartMaterializer
   final case class MaterializerStarted(materializer: Materializer)
 
   // this is available to keep backwards compatibility with ActorMaterializer and should
diff --git a/akka-stream/src/main/scala/akka/stream/impl/TraversalBuilder.scala b/akka-stream/src/main/scala/akka/stream/impl/TraversalBuilder.scala
index 7f9575d0d7..aeb431fa03 100644
--- a/akka-stream/src/main/scala/akka/stream/impl/TraversalBuilder.scala
+++ b/akka-stream/src/main/scala/akka/stream/impl/TraversalBuilder.scala
@@ -180,7 +180,7 @@ import akka.util.unused
 /**
  * INTERNAL API
  */
-@InternalApi private[akka] final case object PopAttributes extends Traversal
+@InternalApi private[akka] case object PopAttributes extends Traversal
 
 /**
  * INTERNAL API
@@ -190,7 +190,7 @@ import akka.util.unused
 /**
  * INTERNAL API
  */
-@InternalApi private[akka] final case object ExitIsland extends Traversal
+@InternalApi private[akka] case object ExitIsland extends Traversal
 
 /**
  * INTERNAL API
diff --git a/akka-stream/src/main/scala/akka/stream/impl/streamref/StreamRefsProtocol.scala b/akka-stream/src/main/scala/akka/stream/impl/streamref/StreamRefsProtocol.scala
index 2a89a21caa..6cba371323 100644
--- a/akka-stream/src/main/scala/akka/stream/impl/streamref/StreamRefsProtocol.scala
+++ b/akka-stream/src/main/scala/akka/stream/impl/streamref/StreamRefsProtocol.scala
@@ -72,6 +72,6 @@ private[akka] object StreamRefsProtocol {
    * Ack that failure or completion has been seen and the remote side can stop
    */
   @InternalApi
-  private[akka] final case object Ack extends StreamRefsProtocol with DeadLetterSuppression
+  private[akka] case object Ack extends StreamRefsProtocol with DeadLetterSuppression
 
 }
diff --git a/akka-testkit/src/main/scala/akka/testkit/SocketUtil.scala b/akka-testkit/src/main/scala/akka/testkit/SocketUtil.scala
index d3a2a97906..a179c20590 100644
--- a/akka-testkit/src/main/scala/akka/testkit/SocketUtil.scala
+++ b/akka-testkit/src/main/scala/akka/testkit/SocketUtil.scala
@@ -30,9 +30,9 @@ object SocketUtil {
   }
 
   sealed trait Protocol
-  final case object Tcp extends Protocol
-  final case object Udp extends Protocol
-  final case object Both extends Protocol
+  case object Tcp extends Protocol
+  case object Udp extends Protocol
+  case object Both extends Protocol
 
   /** @return A port on 'localhost' that is currently available */
   def temporaryLocalPort(udp: Boolean = false): Int = temporaryServerAddress("localhost", udp).getPort