diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 5368941f74..795646d08e 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -1186,7 +1186,11 @@ class Formula
   end
 
   def old_installed_formulae
-    alias_path ? self.class.installed_with_alias_path(alias_path) : []
+    # If this formula isn't the current target of the alias,
+    # it doesn't make sense to say that other formulae are older versions of it
+    # because we don't know which came first.
+    return [] if alias_path.nil? || installed_alias_target_changed?
+    self.class.installed_with_alias_path(alias_path) - [self]
   end
 
   # @private