diff --git a/java/downgrades/qlpack.yml b/java/downgrades/qlpack.yml
index b5a0f1bf411..6489ad2d9f6 100644
--- a/java/downgrades/qlpack.yml
+++ b/java/downgrades/qlpack.yml
@@ -2,3 +2,4 @@ name: codeql/java-downgrades
 groups: java
 downgrades: .
 library: true
+warnOnImplicitThis: true
diff --git a/java/ql/consistency-queries/qlpack.yml b/java/ql/consistency-queries/qlpack.yml
index e5ab40251bb..1501c7fa736 100644
--- a/java/ql/consistency-queries/qlpack.yml
+++ b/java/ql/consistency-queries/qlpack.yml
@@ -2,3 +2,4 @@ name: codeql-java-consistency-queries
 version: 0.0.0
 dependencies:
   codeql/java-all: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/examples/qlpack.yml b/java/ql/examples/qlpack.yml
index 25699c305b0..bbd44274625 100644
--- a/java/ql/examples/qlpack.yml
+++ b/java/ql/examples/qlpack.yml
@@ -4,3 +4,4 @@ groups:
   - examples
 dependencies:
   codeql/java-all: ${workspace}
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/all-platforms/java/qlpack.yml b/java/ql/integration-tests/all-platforms/java/qlpack.yml
index 9ead02fc564..4994af85a75 100644
--- a/java/ql/integration-tests/all-platforms/java/qlpack.yml
+++ b/java/ql/integration-tests/all-platforms/java/qlpack.yml
@@ -2,3 +2,4 @@ dependencies:
   codeql/java-all: '*'
   codeql/java-tests: '*'
   codeql/java-queries: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/all-platforms/kotlin/annotation-id-consistency/qlpack.yml b/java/ql/integration-tests/all-platforms/kotlin/annotation-id-consistency/qlpack.yml
index 74fbac535d7..eeaa0e9f1b7 100644
--- a/java/ql/integration-tests/all-platforms/kotlin/annotation-id-consistency/qlpack.yml
+++ b/java/ql/integration-tests/all-platforms/kotlin/annotation-id-consistency/qlpack.yml
@@ -5,3 +5,4 @@ dependencies:
   codeql/java-queries: '*'
 dataExtensions:
   ext/*.model.yml
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/all-platforms/kotlin/default-parameter-mad-flow/qlpack.yml b/java/ql/integration-tests/all-platforms/kotlin/default-parameter-mad-flow/qlpack.yml
index f1e981e8791..61fd32f9eb9 100644
--- a/java/ql/integration-tests/all-platforms/kotlin/default-parameter-mad-flow/qlpack.yml
+++ b/java/ql/integration-tests/all-platforms/kotlin/default-parameter-mad-flow/qlpack.yml
@@ -5,3 +5,4 @@ dependencies:
   codeql/java-queries: '*'
 dataExtensions:
   ext/*.model.yml
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/all-platforms/kotlin/gradle_kotlinx_serialization/qlpack.yml b/java/ql/integration-tests/all-platforms/kotlin/gradle_kotlinx_serialization/qlpack.yml
index 8b18f2ea94a..d9848346b6f 100644
--- a/java/ql/integration-tests/all-platforms/kotlin/gradle_kotlinx_serialization/qlpack.yml
+++ b/java/ql/integration-tests/all-platforms/kotlin/gradle_kotlinx_serialization/qlpack.yml
@@ -3,3 +3,4 @@ dependencies:
   codeql/java-all: '*'
   codeql/java-tests: '*'
   codeql/java-queries: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/all-platforms/kotlin/kotlin-interface-inherited-default/qlpack.yml b/java/ql/integration-tests/all-platforms/kotlin/kotlin-interface-inherited-default/qlpack.yml
index 814d1059ed5..69d3f0b3658 100644
--- a/java/ql/integration-tests/all-platforms/kotlin/kotlin-interface-inherited-default/qlpack.yml
+++ b/java/ql/integration-tests/all-platforms/kotlin/kotlin-interface-inherited-default/qlpack.yml
@@ -3,3 +3,4 @@ dependencies:
   codeql/java-all: '*'
   codeql/java-tests: '*'
   codeql/java-queries: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/all-platforms/kotlin/kotlin_java_static_fields/qlpack.yml b/java/ql/integration-tests/all-platforms/kotlin/kotlin_java_static_fields/qlpack.yml
index ecc3ee3e4ff..1902aa3a68f 100644
--- a/java/ql/integration-tests/all-platforms/kotlin/kotlin_java_static_fields/qlpack.yml
+++ b/java/ql/integration-tests/all-platforms/kotlin/kotlin_java_static_fields/qlpack.yml
@@ -3,3 +3,4 @@ dependencies:
   codeql/java-all: '*'
   codeql/java-tests: '*'
   codeql/java-queries: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/all-platforms/kotlin/qlpack.yml b/java/ql/integration-tests/all-platforms/kotlin/qlpack.yml
index 9ead02fc564..4994af85a75 100644
--- a/java/ql/integration-tests/all-platforms/kotlin/qlpack.yml
+++ b/java/ql/integration-tests/all-platforms/kotlin/qlpack.yml
@@ -2,3 +2,4 @@ dependencies:
   codeql/java-all: '*'
   codeql/java-tests: '*'
   codeql/java-queries: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/linux-only/kotlin/custom_plugin/qlpack.yml b/java/ql/integration-tests/linux-only/kotlin/custom_plugin/qlpack.yml
index e2f6b6de7ba..18ab2b37444 100644
--- a/java/ql/integration-tests/linux-only/kotlin/custom_plugin/qlpack.yml
+++ b/java/ql/integration-tests/linux-only/kotlin/custom_plugin/qlpack.yml
@@ -1,3 +1,4 @@
 name: integrationtest-custom-plugin
 dependencies:
   codeql/java-all: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/linux-only/kotlin/qlpack.yml b/java/ql/integration-tests/linux-only/kotlin/qlpack.yml
index a1e82f7365a..b2ae6491ab8 100644
--- a/java/ql/integration-tests/linux-only/kotlin/qlpack.yml
+++ b/java/ql/integration-tests/linux-only/kotlin/qlpack.yml
@@ -1,2 +1,3 @@
 dependencies:
   codeql/java-all: '*'
+warnOnImplicitThis: true
diff --git a/java/ql/integration-tests/posix-only/kotlin/qlpack.yml b/java/ql/integration-tests/posix-only/kotlin/qlpack.yml
index 0c0975df53f..4994af85a75 100644
--- a/java/ql/integration-tests/posix-only/kotlin/qlpack.yml
+++ b/java/ql/integration-tests/posix-only/kotlin/qlpack.yml
@@ -2,4 +2,4 @@ dependencies:
   codeql/java-all: '*'
   codeql/java-tests: '*'
   codeql/java-queries: '*'
-
+warnOnImplicitThis: true