diff --git a/sdk/src/main/java/com/bugsnag/android/Client.java b/sdk/src/main/java/com/bugsnag/android/Client.java
index c8d3e27c4e..d45ac6d940 100644
--- a/sdk/src/main/java/com/bugsnag/android/Client.java
+++ b/sdk/src/main/java/com/bugsnag/android/Client.java
@@ -26,7 +26,6 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.Locale;
 import java.util.Map;
 import java.util.Observable;
 import java.util.Observer;
diff --git a/sdk/src/main/java/com/bugsnag/android/Configuration.java b/sdk/src/main/java/com/bugsnag/android/Configuration.java
index 0c84adc217..fe7f954997 100644
--- a/sdk/src/main/java/com/bugsnag/android/Configuration.java
+++ b/sdk/src/main/java/com/bugsnag/android/Configuration.java
@@ -8,7 +8,6 @@
 
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
diff --git a/sdk/src/main/java/com/bugsnag/android/Exceptions.java b/sdk/src/main/java/com/bugsnag/android/Exceptions.java
index 5f38888e48..b5776cf8e7 100644
--- a/sdk/src/main/java/com/bugsnag/android/Exceptions.java
+++ b/sdk/src/main/java/com/bugsnag/android/Exceptions.java
@@ -3,8 +3,6 @@
 import android.support.annotation.NonNull;
 
 import java.io.IOException;
-import java.util.Collections;
-import java.util.List;
 
 /**
  * Unwrap and serialize exception information and any "cause" exceptions.
diff --git a/sdk/src/main/java/com/bugsnag/android/Stacktrace.java b/sdk/src/main/java/com/bugsnag/android/Stacktrace.java
index a3c2cf5f9b..ff136c274b 100644
--- a/sdk/src/main/java/com/bugsnag/android/Stacktrace.java
+++ b/sdk/src/main/java/com/bugsnag/android/Stacktrace.java
@@ -3,7 +3,6 @@
 import android.support.annotation.NonNull;
 
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
diff --git a/sdk/src/main/java/com/bugsnag/android/ThreadState.java b/sdk/src/main/java/com/bugsnag/android/ThreadState.java
index 8e89ab1967..e21ae463f6 100644
--- a/sdk/src/main/java/com/bugsnag/android/ThreadState.java
+++ b/sdk/src/main/java/com/bugsnag/android/ThreadState.java
@@ -6,7 +6,6 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Comparator;
-import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;