diff --git a/api/src/main/java/org/reactivestreams/Processor.java b/api/src/main/java/org/reactivestreams/Processor.java
index b22e25f7..8e4ca3dd 100644
--- a/api/src/main/java/org/reactivestreams/Processor.java
+++ b/api/src/main/java/org/reactivestreams/Processor.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams;
 
 /**
diff --git a/api/src/main/java/org/reactivestreams/Publisher.java b/api/src/main/java/org/reactivestreams/Publisher.java
index d7ed6abe..caf6343d 100644
--- a/api/src/main/java/org/reactivestreams/Publisher.java
+++ b/api/src/main/java/org/reactivestreams/Publisher.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams;
 
 /**
diff --git a/api/src/main/java/org/reactivestreams/Subscriber.java b/api/src/main/java/org/reactivestreams/Subscriber.java
index 6165352e..b9299ddc 100644
--- a/api/src/main/java/org/reactivestreams/Subscriber.java
+++ b/api/src/main/java/org/reactivestreams/Subscriber.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams;
 
 /**
diff --git a/api/src/main/java/org/reactivestreams/Subscription.java b/api/src/main/java/org/reactivestreams/Subscription.java
index 709ee7c8..c18d0fc9 100644
--- a/api/src/main/java/org/reactivestreams/Subscription.java
+++ b/api/src/main/java/org/reactivestreams/Subscription.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams;
 
 /**
diff --git a/tck/src/main/java/org/reactivestreams/tck/IdentityProcessorVerification.java b/tck/src/main/java/org/reactivestreams/tck/IdentityProcessorVerification.java
index 5a534487..025858c9 100644
--- a/tck/src/main/java/org/reactivestreams/tck/IdentityProcessorVerification.java
+++ b/tck/src/main/java/org/reactivestreams/tck/IdentityProcessorVerification.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Processor;
diff --git a/tck/src/main/java/org/reactivestreams/tck/PublisherVerification.java b/tck/src/main/java/org/reactivestreams/tck/PublisherVerification.java
index d3f58441..617e0673 100644
--- a/tck/src/main/java/org/reactivestreams/tck/PublisherVerification.java
+++ b/tck/src/main/java/org/reactivestreams/tck/PublisherVerification.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Publisher;
diff --git a/tck/src/main/java/org/reactivestreams/tck/SubscriberBlackboxVerification.java b/tck/src/main/java/org/reactivestreams/tck/SubscriberBlackboxVerification.java
index 70cfdb86..d3af02b9 100644
--- a/tck/src/main/java/org/reactivestreams/tck/SubscriberBlackboxVerification.java
+++ b/tck/src/main/java/org/reactivestreams/tck/SubscriberBlackboxVerification.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Publisher;
@@ -521,4 +532,4 @@ public T nextT() throws InterruptedException {
   public void notVerified() {
     throw new SkipException("Not verified using this TCK.");
   }
-}
\ No newline at end of file
+}
diff --git a/tck/src/main/java/org/reactivestreams/tck/SubscriberWhiteboxVerification.java b/tck/src/main/java/org/reactivestreams/tck/SubscriberWhiteboxVerification.java
index 45dec6e1..a4c7d7e2 100644
--- a/tck/src/main/java/org/reactivestreams/tck/SubscriberWhiteboxVerification.java
+++ b/tck/src/main/java/org/reactivestreams/tck/SubscriberWhiteboxVerification.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Publisher;
diff --git a/tck/src/main/java/org/reactivestreams/tck/TestEnvironment.java b/tck/src/main/java/org/reactivestreams/tck/TestEnvironment.java
index 65ef3b01..6b8456f6 100644
--- a/tck/src/main/java/org/reactivestreams/tck/TestEnvironment.java
+++ b/tck/src/main/java/org/reactivestreams/tck/TestEnvironment.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Publisher;
diff --git a/tck/src/main/java/org/reactivestreams/tck/WithHelperPublisher.java b/tck/src/main/java/org/reactivestreams/tck/WithHelperPublisher.java
index a2a1653b..e23780e2 100644
--- a/tck/src/main/java/org/reactivestreams/tck/WithHelperPublisher.java
+++ b/tck/src/main/java/org/reactivestreams/tck/WithHelperPublisher.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Publisher;
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/Function.java b/tck/src/main/java/org/reactivestreams/tck/support/Function.java
index d053e5c6..7aa9d26b 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/Function.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/Function.java
@@ -1,5 +1,16 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 public interface Function<In, Out> {
   public Out apply(In in) throws Throwable;
-}
\ No newline at end of file
+}
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/HelperPublisher.java b/tck/src/main/java/org/reactivestreams/tck/support/HelperPublisher.java
index ba0fce68..5f892885 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/HelperPublisher.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/HelperPublisher.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 import java.util.Collections;
@@ -30,4 +41,4 @@ public HelperPublisher(final int from, final int to, final Function<Integer, T>
           }
         }, executor);
     }
-}
\ No newline at end of file
+}
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/InfiniteHelperPublisher.java b/tck/src/main/java/org/reactivestreams/tck/support/InfiniteHelperPublisher.java
index 94897e4b..7237c0a1 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/InfiniteHelperPublisher.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/InfiniteHelperPublisher.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 import org.reactivestreams.example.unicast.AsyncIterablePublisher;
@@ -27,4 +38,4 @@ public InfiniteHelperPublisher(final Function<Integer, T> create, final Executor
           }
         }, executor);
     }
-}
\ No newline at end of file
+}
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/NonFatal.java b/tck/src/main/java/org/reactivestreams/tck/support/NonFatal.java
index b6dedd4b..6b3a215f 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/NonFatal.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/NonFatal.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/Optional.java b/tck/src/main/java/org/reactivestreams/tck/support/Optional.java
index 82caa985..e533c65e 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/Optional.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/Optional.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 import java.util.NoSuchElementException;
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/PublisherVerificationRules.java b/tck/src/main/java/org/reactivestreams/tck/support/PublisherVerificationRules.java
index a6c67dc7..5a3116bd 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/PublisherVerificationRules.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/PublisherVerificationRules.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBlackboxVerificationRules.java b/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBlackboxVerificationRules.java
index 463f225b..69e9628c 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBlackboxVerificationRules.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBlackboxVerificationRules.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 /**
@@ -30,4 +41,4 @@ public interface SubscriberBlackboxVerificationRules {
   void untested_spec314_blackbox_cancelMayCauseThePublisherToShutdownIfNoOtherSubscriptionExists() throws Exception;
   void untested_spec315_blackbox_cancelMustNotThrowExceptionAndMustSignalOnError() throws Exception;
   void untested_spec316_blackbox_requestMustNotThrowExceptionAndMustOnErrorTheSubscriber() throws Exception;
-}
\ No newline at end of file
+}
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBufferOverflowException.java b/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBufferOverflowException.java
index c7150cfc..ebbe0f0b 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBufferOverflowException.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/SubscriberBufferOverflowException.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 public final class SubscriberBufferOverflowException extends RuntimeException {
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/SubscriberWhiteboxVerificationRules.java b/tck/src/main/java/org/reactivestreams/tck/support/SubscriberWhiteboxVerificationRules.java
index 60d9df2a..3d812626 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/SubscriberWhiteboxVerificationRules.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/SubscriberWhiteboxVerificationRules.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 /**
@@ -32,4 +43,4 @@ public interface SubscriberWhiteboxVerificationRules {
   void untested_spec314_cancelMayCauseThePublisherToShutdownIfNoOtherSubscriptionExists() throws Exception;
   void untested_spec315_cancelMustNotThrowExceptionAndMustSignalOnError() throws Exception;
   void untested_spec316_requestMustNotThrowExceptionAndMustOnErrorTheSubscriber() throws Exception;
-}
\ No newline at end of file
+}
diff --git a/tck/src/main/java/org/reactivestreams/tck/support/TestException.java b/tck/src/main/java/org/reactivestreams/tck/support/TestException.java
index 21e13ca3..fb395111 100644
--- a/tck/src/main/java/org/reactivestreams/tck/support/TestException.java
+++ b/tck/src/main/java/org/reactivestreams/tck/support/TestException.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 /**
diff --git a/tck/src/test/java/org/reactivestreams/tck/EmptyLazyPublisherTest.java b/tck/src/test/java/org/reactivestreams/tck/EmptyLazyPublisherTest.java
index 0c22486f..1ae262b4 100644
--- a/tck/src/test/java/org/reactivestreams/tck/EmptyLazyPublisherTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/EmptyLazyPublisherTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.example.unicast.AsyncIterablePublisher;
@@ -39,4 +50,4 @@ public Publisher<Integer> createFailedPublisher() {
   public long maxElementsFromPublisher() {
     return 0;
   }
-}
\ No newline at end of file
+}
diff --git a/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationDelegationTest.java b/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationDelegationTest.java
index e37eca5a..ac0cd76c 100644
--- a/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationDelegationTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationDelegationTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.testng.annotations.Test;
diff --git a/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationTest.java b/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationTest.java
index 435ecced..76472120 100644
--- a/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/IdentityProcessorVerificationTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Processor;
diff --git a/tck/src/test/java/org/reactivestreams/tck/PublisherVerificationTest.java b/tck/src/test/java/org/reactivestreams/tck/PublisherVerificationTest.java
index 1911f18a..37f8c83a 100644
--- a/tck/src/test/java/org/reactivestreams/tck/PublisherVerificationTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/PublisherVerificationTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Publisher;
diff --git a/tck/src/test/java/org/reactivestreams/tck/SingleElementPublisherTest.java b/tck/src/test/java/org/reactivestreams/tck/SingleElementPublisherTest.java
index f847b113..f3d3f905 100644
--- a/tck/src/test/java/org/reactivestreams/tck/SingleElementPublisherTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/SingleElementPublisherTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Publisher;
@@ -39,4 +50,4 @@ public Publisher<Integer> createFailedPublisher() {
   public long maxElementsFromPublisher() {
     return 1;
   }
-}
\ No newline at end of file
+}
diff --git a/tck/src/test/java/org/reactivestreams/tck/SubscriberBlackboxVerificationTest.java b/tck/src/test/java/org/reactivestreams/tck/SubscriberBlackboxVerificationTest.java
index 4e31ffc2..38703f7d 100644
--- a/tck/src/test/java/org/reactivestreams/tck/SubscriberBlackboxVerificationTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/SubscriberBlackboxVerificationTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Subscriber;
diff --git a/tck/src/test/java/org/reactivestreams/tck/SubscriberWhiteboxVerificationTest.java b/tck/src/test/java/org/reactivestreams/tck/SubscriberWhiteboxVerificationTest.java
index ed4b7e9e..4a0b9c0c 100644
--- a/tck/src/test/java/org/reactivestreams/tck/SubscriberWhiteboxVerificationTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/SubscriberWhiteboxVerificationTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Subscriber;
diff --git a/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberTest.java b/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberTest.java
index 0b099fcf..f04e2f2b 100644
--- a/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Subscriber;
diff --git a/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberWhiteboxTest.java b/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberWhiteboxTest.java
index fb85a434..d14f4488 100644
--- a/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberWhiteboxTest.java
+++ b/tck/src/test/java/org/reactivestreams/tck/SyncTriggeredDemandSubscriberWhiteboxTest.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck;
 
 import org.reactivestreams.Subscriber;
diff --git a/tck/src/test/java/org/reactivestreams/tck/support/SyncTriggeredDemandSubscriber.java b/tck/src/test/java/org/reactivestreams/tck/support/SyncTriggeredDemandSubscriber.java
index ba6bb7a0..eb9fd7a3 100644
--- a/tck/src/test/java/org/reactivestreams/tck/support/SyncTriggeredDemandSubscriber.java
+++ b/tck/src/test/java/org/reactivestreams/tck/support/SyncTriggeredDemandSubscriber.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 import org.reactivestreams.Subscriber;
@@ -120,4 +131,4 @@ private void done() {
       // And anyway, the `Subscription` is considered to be cancelled if this method gets called, as per rule 2.4
     }
   }
-}
\ No newline at end of file
+}
diff --git a/tck/src/test/java/org/reactivestreams/tck/support/TCKVerificationSupport.java b/tck/src/test/java/org/reactivestreams/tck/support/TCKVerificationSupport.java
index 8aa396e5..b5067da7 100644
--- a/tck/src/test/java/org/reactivestreams/tck/support/TCKVerificationSupport.java
+++ b/tck/src/test/java/org/reactivestreams/tck/support/TCKVerificationSupport.java
@@ -1,3 +1,14 @@
+/************************************************************************
+ * Licensed under Public Domain (CC0)                                    *
+ *                                                                       *
+ * To the extent possible under law, the person who associated CC0 with  *
+ * this code has waived all copyright and related or neighboring         *
+ * rights to this code.                                                  *
+ *                                                                       *
+ * You should have received a copy of the CC0 legalcode along with this  *
+ * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.*
+ ************************************************************************/
+
 package org.reactivestreams.tck.support;
 
 import org.reactivestreams.Publisher;