diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/AntlrTokenFilter.java b/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/AntlrTokenFilter.java
index f0f6d71e27..c76332d69e 100644
--- a/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/AntlrTokenFilter.java
+++ b/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/AntlrTokenFilter.java
@@ -6,6 +6,7 @@ package net.sourceforge.pmd.cpd.token;
 
 import static org.antlr.v4.runtime.Token.EOF;
 
+import net.sourceforge.pmd.cpd.token.internal.BaseTokenFilter;
 import net.sourceforge.pmd.lang.antlr.AntlrTokenManager;
 
 /**
diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/JavaCCTokenFilter.java b/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/JavaCCTokenFilter.java
index 734b9fcff3..b8feec5f64 100644
--- a/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/JavaCCTokenFilter.java
+++ b/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/JavaCCTokenFilter.java
@@ -4,6 +4,7 @@
 
 package net.sourceforge.pmd.cpd.token;
 
+import net.sourceforge.pmd.cpd.token.internal.BaseTokenFilter;
 import net.sourceforge.pmd.lang.TokenManager;
 import net.sourceforge.pmd.lang.ast.GenericToken;
 
diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/BaseTokenFilter.java b/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/internal/BaseTokenFilter.java
similarity index 96%
rename from pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/BaseTokenFilter.java
rename to pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/internal/BaseTokenFilter.java
index c5451fa9ed..0f43a305fb 100644
--- a/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/BaseTokenFilter.java
+++ b/pmd-core/src/main/java/net/sourceforge/pmd/cpd/token/internal/BaseTokenFilter.java
@@ -2,8 +2,9 @@
  * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
  */
 
-package net.sourceforge.pmd.cpd.token;
+package net.sourceforge.pmd.cpd.token.internal;
 
+import net.sourceforge.pmd.cpd.token.TokenFilter;
 import net.sourceforge.pmd.lang.TokenManager;
 import net.sourceforge.pmd.lang.ast.GenericToken;