diff --git a/src/sys/options.cxx b/src/sys/options.cxx
index d1249b7c74..62a17270fb 100644
--- a/src/sys/options.cxx
+++ b/src/sys/options.cxx
@@ -262,10 +262,21 @@ Options& Options::operator=(Options&& other) noexcept {
   children = std::move(other.children);
   value_used = other.value_used;
 
+  size_t len = other.full_name.size();
+  std::string new_prefix;
+  if (len == 0) {
+    new_prefix = full_name.empty() ? full_name : full_name + ":";
+  } else {
+    new_prefix = full_name;
+    // If new_prefix is empty but the old name is not then we also
+    // need to remove a colon when updating names
+    if (full_name.empty()) {
+      len += 1;
+    }
+  }
+
   // Ensure that this is the parent of all children,
   // otherwise will point to the original Options instance
-  const auto len = other.full_name.size();
-  const std::string new_prefix = len == 0 ? full_name + ":" : full_name;
   for (auto& child : children) {
     child.second.parent_instance = this;
     child.second.recursively_update_names(len, new_prefix);
diff --git a/tests/unit/sys/test_options.cxx b/tests/unit/sys/test_options.cxx
index 110943e71a..4dcb858863 100644
--- a/tests/unit/sys/test_options.cxx
+++ b/tests/unit/sys/test_options.cxx
@@ -660,6 +660,19 @@ TEST_F(OptionsTest, AssignOption) {
   EXPECT_EQ(option2.as<int>(), 42);
 }
 
+TEST_F(OptionsTest, AssignOptionName) {
+  Options option1, option2, option3;
+
+  option1 = 42;
+
+  option2 = option1.copy();
+  option3["key"] = option1.copy();
+
+  EXPECT_EQ(option2.str(), "");
+  EXPECT_EQ(option3.str(), "");
+  EXPECT_EQ(option3["key"].str(), "key");
+}
+
 TEST_F(OptionsTest, AssignSection) {
   Options option1, option2;
 
@@ -672,13 +685,16 @@ TEST_F(OptionsTest, AssignSection) {
 }
 
 TEST_F(OptionsTest, AssignSectionName) {
-  Options option1, option2;
+  Options option1, option2, option3;
 
   option1["key"] = 42;
 
-  option2 = option1["key"].copy();
+  option2 = option1.copy();
+  option3 = option1["key"].copy();
 
   EXPECT_EQ(option2.str(), "");
+  EXPECT_EQ(option2["key"].str(), "key");
+  EXPECT_EQ(option3.str(), "");
 }
 
 TEST_F(OptionsTest, AssignSectionReplace) {
@@ -713,18 +729,19 @@ TEST_F(OptionsTest, AssignSubSection) {
 }
 
 TEST_F(OptionsTest, AssignSubSectionName) {
-  Options option1, option2, option3;
+  Options option1, option2, option3, option4;
 
   option1["key1"] = 42;
-
   option2["key2"] = option1.copy();
-
   option3["key3"] = option2["key2"].copy();
+  option4 = option2["key2"].copy();
 
   EXPECT_EQ(option2["key2"].str(), "key2");
   EXPECT_EQ(option2["key2"]["key1"].str(), "key2:key1");
-  EXPECT_EQ(option2["key3"]["key2"].str(), "key3:key2");
-  EXPECT_EQ(option2["key3"]["key2"]["key1"].str(), "key3:key2:key1");
+  EXPECT_EQ(option3["key3"]["key2"].str(), "key3:key2");
+  EXPECT_EQ(option3["key3"]["key2"]["key1"].str(), "key3:key2:key1");
+  EXPECT_EQ(option4.str(), "");
+  EXPECT_EQ(option4["key1"].str(), "key1");
 }
 
 TEST_F(OptionsTest, AssignSubSectionParent) {