diff --git a/processor/src/main/java/org/mapstruct/ap/spi/FreeBuilderAccessorNamingStrategy.java b/processor/src/main/java/org/mapstruct/ap/spi/FreeBuilderAccessorNamingStrategy.java
index f2d3c3402d..5b269b4b06 100644
--- a/processor/src/main/java/org/mapstruct/ap/spi/FreeBuilderAccessorNamingStrategy.java
+++ b/processor/src/main/java/org/mapstruct/ap/spi/FreeBuilderAccessorNamingStrategy.java
@@ -7,6 +7,8 @@
 
 import javax.lang.model.element.ExecutableElement;
 
+import org.mapstruct.util.Experimental;
+
 /**
  * Accessor naming strategy for FreeBuilder.
  * FreeBuilder adds a lot of other methods that can be considered as fluent setters. Such as:
@@ -24,6 +26,7 @@
  *
  * @author Filip Hrisafov
  */
+@Experimental("The FreeBuilder accessor naming strategy might change in a subsequent release")
 public class FreeBuilderAccessorNamingStrategy extends DefaultAccessorNamingStrategy {
 
     @Override
diff --git a/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesAccessorNamingStrategy.java b/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesAccessorNamingStrategy.java
index cc1d66895d..abe777a1c4 100644
--- a/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesAccessorNamingStrategy.java
+++ b/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesAccessorNamingStrategy.java
@@ -7,6 +7,8 @@
 
 import javax.lang.model.element.ExecutableElement;
 
+import org.mapstruct.util.Experimental;
+
 /**
  * Accesor naming strategy for Immutables.
  * The generated Immutables also have a from that works as a copy. Our default strategy considers this method
@@ -14,6 +16,7 @@
  *
  * @author Filip Hrisafov
  */
+@Experimental("The Immutables accessor naming strategy might change in a subsequent release")
 public class ImmutablesAccessorNamingStrategy extends DefaultAccessorNamingStrategy {
 
     @Override
diff --git a/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesBuilderProvider.java b/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesBuilderProvider.java
index 0da8b03161..16ad797a92 100644
--- a/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesBuilderProvider.java
+++ b/processor/src/main/java/org/mapstruct/ap/spi/ImmutablesBuilderProvider.java
@@ -13,6 +13,8 @@
 import javax.lang.model.element.PackageElement;
 import javax.lang.model.element.TypeElement;
 
+import org.mapstruct.util.Experimental;
+
 /**
  * Builder provider for Immutables. A custom provider is needed because Immutables creates an implementation of an
  * interface and that implementation has the builder. This implementation would try to find the type created by
@@ -21,6 +23,7 @@
  *
  * @author Filip Hrisafov
  */
+@Experimental("The Immutables builder provider might change in a subsequent release")
 public class ImmutablesBuilderProvider extends DefaultBuilderProvider {
 
     private static final Pattern JAVA_JAVAX_PACKAGE = Pattern.compile( "^javax?\\..*" );