diff --git a/app/models/gem_typo.rb b/app/models/gem_typo.rb
index 0b266056003..d0585e286cc 100644
--- a/app/models/gem_typo.rb
+++ b/app/models/gem_typo.rb
@@ -1,46 +1,42 @@
-require 'rubygems/text'
+require "rubygems/text"
 
 class GemTypo
-  PROTECTED_GEMS = [
-    'rspec-core',
-    'diff-lcs',
-    'rspec-expectations',
-    'rspec-mocks',
-    'rspec',
-    'bundler',
-    'rspec-support',
-    'multi_json',
-    'rack',
-    'rake'
-  ].freeze
-
-  DISTANCE_THRESHOLD = 1
-
-  GEM_EXCEPTIONS = [
-    'rspec-coreZ'
-    # Add exceptions here to manage gems which share a close distance,
-    # but are manually reviewed and accepted by rubygems team
-  ].freeze
+  attr_reader :protected_gem
 
   include Gem::Text
 
-  def initialize(rubygem_name, opts = {})
-    @rubygem_name = rubygem_name
-    @protected_gems = opts[:protected_gems] || GemTypo::PROTECTED_GEMS
-    @distance_threshold = opts[:distance_threshold] || GemTypo::DISTANCE_THRESHOLD
-    @gem_exceptions = opts[:gem_exceptions] || GemTypo::GEM_EXCEPTIONS
+  DOWNLOADS_THRESHOLD = 10_000_000
+  SIZE_THRESHOLD = 4
+
+  def initialize(rubygem_name)
+    @rubygem_name       = rubygem_name.downcase
+    @distance_threshold = distance_threshold
   end
 
   def protected_typo?
-    @protected_gems.each do |protected_gem|
-      return false if @rubygem_name == protected_gem
+    return false if @rubygem_name.size < GemTypo::SIZE_THRESHOLD
+
+    protected_gems.each do |protected_gem|
       distance = levenshtein_distance(@rubygem_name, protected_gem)
-      if distance <= @distance_threshold &&
-          !@gem_exceptions.include?(@rubygem_name)
+      if distance <= @distance_threshold
+        @protected_gem = protected_gem
         return true
       end
     end
 
     false
   end
+
+  private
+
+  def distance_threshold
+    @rubygem_name.size == GemTypo::SIZE_THRESHOLD ? 1 : 2
+  end
+
+  def protected_gems
+    Rubygem.joins(:gem_download)
+      .where("gem_downloads.count > ?", GemTypo::DOWNLOADS_THRESHOLD)
+      .where.not(name: @rubygem_name)
+      .pluck(:name)
+  end
 end
diff --git a/app/models/rubygem.rb b/app/models/rubygem.rb
index 21ddee42a6e..49f6b9ddce5 100644
--- a/app/models/rubygem.rb
+++ b/app/models/rubygem.rb
@@ -18,7 +18,7 @@ class Rubygem < ApplicationRecord
     uniqueness: { case_sensitive: false },
     if: :needs_name_validation?
   validate :blacklist_names_exclusion
-  validate :protected_gem_typo_protection
+  validate :protected_gem_typo, on: :create
 
   after_create :update_unresolved
   before_destroy :mark_unresolved
@@ -309,10 +309,11 @@ def blacklist_names_exclusion
     errors.add :name, "'#{name}' is a reserved gem name."
   end
 
-  def protected_gem_typo_protection
+  def protected_gem_typo
     gem_typo = GemTypo.new(name)
+
     return unless gem_typo.protected_typo?
-    errors.add :name, "'#{name}' is too close to a typo-protected gem."
+    errors.add :name, "'#{name}' is too close to typo-protected gem: #{gem_typo.protected_gem}"
   end
 
   def update_unresolved
diff --git a/test/functional/api/v1/rubygems_controller_test.rb b/test/functional/api/v1/rubygems_controller_test.rb
index 0a9f3076502..2a2108fb394 100644
--- a/test/functional/api/v1/rubygems_controller_test.rb
+++ b/test/functional/api/v1/rubygems_controller_test.rb
@@ -308,6 +308,20 @@ def self.should_respond_to(format)
       end
     end
 
+    context "On POST to create with a protected gem name" do
+      setup do
+        above_downloads_thres = GemTypo::DOWNLOADS_THRESHOLD + 1
+        create(:rubygem, name: "best", downloads: above_downloads_thres)
+        post :create, body: gem_file("test-1.0.0.gem").read
+      end
+
+      should respond_with :forbidden
+      should "not register new gem" do
+        assert_equal 1, Rubygem.count
+        assert_equal "There was a problem saving your gem: Name 'test' is too close to typo-protected gem: best", @response.body
+      end
+    end
+
     context "On POST to create for someone else's gem" do
       setup do
         @other_user = create(:user)
diff --git a/test/unit/gem_typo_test.rb b/test/unit/gem_typo_test.rb
index 90ebbc41f9c..7fa51811d95 100644
--- a/test/unit/gem_typo_test.rb
+++ b/test/unit/gem_typo_test.rb
@@ -1,78 +1,44 @@
-require 'test_helper'
-require 'gem_typo'
+require "test_helper"
 
 class GemTypoTest < ActiveSupport::TestCase
-  teardown do
-    Rails.cache.clear
-  end
-
-  should 'return false for exact match' do
-    gem_typo = GemTypo.new('rspec-core')
-    assert_equal false, gem_typo.protected_typo?
-  end
-
-  should 'return true for 1 char distance match' do
-    gem_typo = GemTypo.new('rspec-core2')
-    assert_equal true, gem_typo.protected_typo?
-  end
-
-  should 'return false for 2 char distance match' do
-    gem_typo = GemTypo.new('rspec-core12')
-    assert_equal false, gem_typo.protected_typo?
-  end
-
-  should 'return false for 3 char distance match' do
-    gem_typo = GemTypo.new('rspec-core123')
-    assert_equal false, gem_typo.protected_typo?
-  end
-
-  should 'return false for 1 char distance match on the exception list' do
-    gem_typo = GemTypo.new('rspec-coreZ')
-    assert_equal false, gem_typo.protected_typo?
-  end
-
-  should 'allow customized protected_gems' do
-    opts = {
-      protected_gems: ["hello"]
-    }
-
-    gem_typo = GemTypo.new('hello', opts)
-    assert_equal false, gem_typo.protected_typo?
-
-    gem_typo = GemTypo.new('hello1', opts)
-    assert_equal true, gem_typo.protected_typo?
-  end
-
-  should 'allow customized distance_threshold' do
-    opts = {
-      distance_threshold: 3
-    }
-
-    gem_typo = GemTypo.new('rack', opts)
-    assert_equal false, gem_typo.protected_typo?
-
-    gem_typo = GemTypo.new('rack1', opts)
-    assert_equal true, gem_typo.protected_typo?
-
-    gem_typo = GemTypo.new('rack12', opts)
-    assert_equal true, gem_typo.protected_typo?
-
-    gem_typo = GemTypo.new('rack123', opts)
-    assert_equal true, gem_typo.protected_typo?
-
-    gem_typo = GemTypo.new('rack1234', opts)
-    assert_equal false, gem_typo.protected_typo?
-  end
-
-  should 'allow customized protected_gem_exceptions' do
-    opts = {
-      gem_exceptions: ["rake1"]
-    }
-
-    gem_typo = GemTypo.new('rake', opts)
-    assert_equal false, gem_typo.protected_typo?
-
-    gem_typo = GemTypo.new('rake1', opts)
-    assert_equal false, gem_typo.protected_typo?
+  context "with above downloads threshold gem" do
+    setup do
+      above_downloads_thres = GemTypo::DOWNLOADS_THRESHOLD + 1
+      create(:rubygem, name: "four", downloads: above_downloads_thres)
+    end
+
+    should "return false for exact match" do
+      gem_typo = GemTypo.new("four")
+      assert_equal false, gem_typo.protected_typo?
+    end
+
+    should "return false for gem name size below protected threshold" do
+      gem_typo = GemTypo.new("fou")
+      assert_equal false, gem_typo.protected_typo?
+    end
+
+    context "size equals protected threshold" do
+      should "return true for one character distance" do
+        gem_typo = GemTypo.new("fous")
+        assert_equal true, gem_typo.protected_typo?
+      end
+
+      should "return false for two character distance" do
+        gem_typo = GemTypo.new("foss")
+        assert_equal false, gem_typo.protected_typo?
+      end
+    end
+
+    context "size above protected threshold" do
+      should "return true for two character distance" do
+        gem_typo = GemTypo.new("fourss")
+        assert_equal true, gem_typo.protected_typo?
+      end
+
+      should "return false for three characher distance" do
+        gem_typo = GemTypo.new("foursss")
+        assert_equal false, gem_typo.protected_typo?
+      end
+    end
   end
 end