diff --git a/regression/jbmc-strings/java_append_object/test.desc b/regression/jbmc-strings/java_append_object/test.desc
index 2af06f2686a..ce08e3e17ad 100644
--- a/regression/jbmc-strings/java_append_object/test.desc
+++ b/regression/jbmc-strings/java_append_object/test.desc
@@ -5,3 +5,5 @@ test_append_object.class
 ^SIGNAL=0$
 ^\[.*assertion\.1\].* line 15.* FAILURE$
 --
+--
+Issue: diffblue/test-gen#82
diff --git a/regression/strings-smoke-tests/cprover/CProverString.class b/regression/strings-smoke-tests/cprover/CProverString.class
deleted file mode 100644
index 8eb78d4aaa4..00000000000
Binary files a/regression/strings-smoke-tests/cprover/CProverString.class and /dev/null differ
diff --git a/regression/strings-smoke-tests/cprover/CProverString.java b/regression/strings-smoke-tests/cprover/CProverString.java
deleted file mode 100644
index 0603aac5dc6..00000000000
--- a/regression/strings-smoke-tests/cprover/CProverString.java
+++ /dev/null
@@ -1,150 +0,0 @@
-package org.cprover;
-
-public final class CProverString {
-    public static char charAt(String s, int i) {
-        if (0 <= i && i < s.length())
-            return s.charAt(i);
-        else
-            return '\u0000';
-    }
-
-    public static int codePointAt(String s, int index) {
-        return s.codePointAt(index);
-    }
-
-    public static int codePointBefore(String s, int index) {
-        return s.codePointBefore(index);
-    }
-
-    public static int codePointCount(
-            String s, int beginIndex, int endIndex) {
-        return s.codePointCount(beginIndex, endIndex);
-    }
-
-    public static int offsetByCodePoints(
-            String s, int index, int codePointOffset) {
-        return s.offsetByCodePoints(index, codePointOffset);
-    }
-
-    public static CharSequence subSequence(
-            String s, int beginIndex, int endIndex) {
-        return s.subSequence(beginIndex, endIndex);
-    }
-
-    public static String substring(String s, int i) {
-        if (i <= 0)
-            return s;
-        else if (i >= s.length())
-            return "";
-        else
-            return s.substring(i);
-    }
-
-    public static String substring(String s, int i, int j) {
-        if (i < 0)
-            return substring(s, 0, j);
-        if (j >= s.length())
-            return substring(s, 0, s.length() - 1);
-        if (i >= j)
-            return "";
-        return s.substring(i, j);
-    }
-
-    public static StringBuilder append(
-            StringBuilder sb, CharSequence cs, int i, int j) {
-        return sb.append(cs, i, j);
-    }
-
-    public static StringBuilder delete(StringBuilder sb, int start, int end) {
-        return sb.delete(start, end);
-    }
-
-    public static StringBuilder deleteCharAt(StringBuilder sb, int index) {
-        return sb.deleteCharAt(index);
-    }
-
-    public static StringBuilder insert(
-            StringBuilder sb, int offset, String str) {
-        return sb.insert(offset, str);
-    }
-
-    public static StringBuilder insert(
-            StringBuilder sb, int offset, boolean b) {
-        return sb.insert(offset, b);
-    }
-
-    public static StringBuilder insert(
-            StringBuilder sb, int offset, char c) {
-        return sb.insert(offset, c);
-    }
-
-    public static StringBuilder insert(
-            StringBuilder sb, int offset, int i) {
-        return sb.insert(offset, i);
-    }
-
-    public static StringBuilder insert(
-            StringBuilder sb, int offset, long l) {
-        return sb.insert(offset, l);
-    }
-
-    public static StringBuilder insert(
-            StringBuilder sb, int offset, float f) {
-        return sb.insert(offset, f);
-    }
-
-    public static StringBuilder insert(
-            StringBuilder sb, int offset, double d) {
-        return sb.insert(offset, d);
-    }
-
-    public static void setLength(StringBuffer sb, int newLength) {
-        sb.setLength(newLength);
-    }
-
-    public static char charAt(StringBuffer sb, int index) {
-        return sb.charAt(index);
-    }
-
-    public static void setCharAt(StringBuffer sb, int index, char c) {
-        sb.setCharAt(index, c);
-    }
-
-    public static StringBuffer delete(
-            StringBuffer sb, int start, int end) {
-        return sb.delete(start, end);
-    }
-
-    public static StringBuffer deleteCharAt(StringBuffer sb, int index) {
-        return sb.deleteCharAt(index);
-    }
-
-    public static String substring(StringBuffer sb, int start, int end) {
-        return sb.substring(start, end);
-    }
-
-    public static StringBuffer insert(
-            StringBuffer sb, int offset, String str) {
-        return sb.insert(offset, str);
-    }
-
-    public static StringBuffer insert(
-            StringBuffer sb, int offset, boolean b) {
-        return sb.insert(offset, b);
-    }
-
-    public static StringBuffer insert(
-            StringBuffer sb, int offset, char c) {
-        return sb.insert(offset, c);
-    }
-
-    public static StringBuffer insert(
-            StringBuffer sb, int offset, int i) {
-        return sb.insert(offset, i);
-    }
-
-    public static StringBuffer insert(
-            StringBuffer sb, int offset, long l) {
-        return sb.insert(offset, l);
-    }
-}
diff --git a/regression/strings-smoke-tests/java_append_int/test.desc b/regression/strings-smoke-tests/java_append_int/test.desc
deleted file mode 100644
index 71e874d2486..00000000000
--- a/regression/strings-smoke-tests/java_append_int/test.desc
+++ /dev/null
@@ -1,8 +0,0 @@
-FUTURE
-test_append_int.class
---refine-strings --verbosity 10 --string-max-length 1000
-^EXIT=0$
-^SIGNAL=0$
-^VERIFICATION SUCCESSFUL$
---
-non equal types
diff --git a/regression/strings-smoke-tests/java_append_int/test_append_int.class b/regression/strings-smoke-tests/java_append_int/test_append_int.class
deleted file mode 100644
index 16948397e03..00000000000
Binary files a/regression/strings-smoke-tests/java_append_int/test_append_int.class and /dev/null differ
diff --git a/regression/strings-smoke-tests/java_append_int/test_append_int.java b/regression/strings-smoke-tests/java_append_int/test_append_int.java
deleted file mode 100644
index 963f3d7c063..00000000000
--- a/regression/strings-smoke-tests/java_append_int/test_append_int.java
+++ /dev/null
@@ -1,11 +0,0 @@
-public class test_append_int
-{
-   public static void main(/*String[] args*/)
-   {
-      StringBuilder diffblue = new StringBuilder();
-      diffblue.append("d");
-      diffblue.append(4);
-      String s = diffblue.toString();
-      assert s.equals("d4");
-   }
-}
diff --git a/regression/strings-smoke-tests/java_append_object/test.desc b/regression/strings-smoke-tests/java_append_object/test.desc
deleted file mode 100644
index c905a3990f6..00000000000
--- a/regression/strings-smoke-tests/java_append_object/test.desc
+++ /dev/null
@@ -1,10 +0,0 @@
-FUTURE
-test_append_object.class
---refine-strings --verbosity 10 --string-max-length 1000
-^EXIT=0$
-^SIGNAL=0$
-^VERIFICATION SUCCESSFUL$
---
-non equal types
---
-Issue: diffblue/test-gen#82
diff --git a/regression/strings-smoke-tests/java_append_object/test_append_object.class b/regression/strings-smoke-tests/java_append_object/test_append_object.class
deleted file mode 100644
index ed6942a1fa6..00000000000
Binary files a/regression/strings-smoke-tests/java_append_object/test_append_object.class and /dev/null differ
diff --git a/regression/strings-smoke-tests/java_append_object/test_append_object.java b/regression/strings-smoke-tests/java_append_object/test_append_object.java
deleted file mode 100644
index 121690451ca..00000000000
--- a/regression/strings-smoke-tests/java_append_object/test_append_object.java
+++ /dev/null
@@ -1,17 +0,0 @@
-public class test_append_object
-{
-   public static void main(/*String[] args*/)
-   {
-      Object diff = "diff";
-      Object blue = "blue";
-
-      StringBuilder buffer = new StringBuilder();
-
-      buffer.append(diff)
-            .append(blue);
-
-      String tmp=buffer.toString();
-      System.out.println(tmp);
-      assert tmp.equals("diffblue");
-   }
-}