diff --git a/Library/Homebrew/cask/lib/hbc/cli.rb b/Library/Homebrew/cask/lib/hbc/cli.rb
index 39235fa63b..3176489cb3 100644
--- a/Library/Homebrew/cask/lib/hbc/cli.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli.rb
@@ -229,9 +229,9 @@ module Hbc
           remaining << head
           retry
         rescue OptionParser::MissingArgument
-          raise CaskError, "The option '#{head}' requires an argument"
+          raise ArgumentError, "The option '#{head}' requires an argument."
         rescue OptionParser::AmbiguousOption
-          raise CaskError, "There is more than one possible option that starts with '#{head}'"
+          raise ArgumentError, "There is more than one possible option that starts with '#{head}'."
         end
       end
 
diff --git a/Library/Homebrew/test/cask/cli/options_spec.rb b/Library/Homebrew/test/cask/cli/options_spec.rb
index 35dafa853d..44a391b489 100644
--- a/Library/Homebrew/test/cask/cli/options_spec.rb
+++ b/Library/Homebrew/test/cask/cli/options_spec.rb
@@ -108,7 +108,7 @@ describe Hbc::CLI, :cask do
     it "shows a user-friendly error message" do
       expect {
         Hbc::CLI.process_options %w[install -f]
-      }.to raise_error(Hbc::CaskError)
+      }.to raise_error(ArgumentError)
     end
   end
 
@@ -116,7 +116,7 @@ describe Hbc::CLI, :cask do
     it "shows a user-friendly error message" do
       expect {
         Hbc::CLI.process_options %w[edit -c]
-      }.to raise_error(Hbc::CaskError)
+      }.to raise_error(ArgumentError)
     end
   end