diff --git a/bundler/lib/bundler/definition.rb b/bundler/lib/bundler/definition.rb
index 09be2db68ca0..044445e11b2d 100644
--- a/bundler/lib/bundler/definition.rb
+++ b/bundler/lib/bundler/definition.rb
@@ -746,17 +746,8 @@ def metadata_dependencies
 
     def ruby_version_requirements(ruby_version)
       return [] unless ruby_version
-      if ruby_version.patchlevel
-        [ruby_version.to_gem_version_with_patchlevel]
-      else
-        ruby_version.versions.map do |version|
-          requirement = Gem::Requirement.new(version)
-          if requirement.exact?
-            "~> #{version}.0"
-          else
-            requirement
-          end
-        end
+      ruby_version.versions.map do |version|
+        Gem::Requirement.new(version)
       end
     end
 
diff --git a/bundler/lib/bundler/ruby_version.rb b/bundler/lib/bundler/ruby_version.rb
index d3b7963920c9..5a2c362677da 100644
--- a/bundler/lib/bundler/ruby_version.rb
+++ b/bundler/lib/bundler/ruby_version.rb
@@ -110,14 +110,6 @@ def self.system
       @ruby_version ||= RubyVersion.new(ruby_version, patchlevel, ruby_engine, ruby_engine_version)
     end
 
-    def to_gem_version_with_patchlevel
-      @gem_version_with_patch ||= begin
-        Gem::Version.create("#{@gem_version}.#{@patchlevel}")
-      rescue ArgumentError
-        @gem_version
-      end
-    end
-
     def exact?
       return @exact if defined?(@exact)
       @exact = versions.all? {|v| Gem::Requirement.create(v).exact? }
diff --git a/bundler/lib/bundler/rubygems_ext.rb b/bundler/lib/bundler/rubygems_ext.rb
index 78422ceb765c..b0e35e005ea2 100644
--- a/bundler/lib/bundler/rubygems_ext.rb
+++ b/bundler/lib/bundler/rubygems_ext.rb
@@ -67,6 +67,23 @@ def gem_dir
       full_gem_path
     end
 
+    unless const_defined?(:LATEST_RUBY_WITHOUT_PATCH_VERSIONS)
+      LATEST_RUBY_WITHOUT_PATCH_VERSIONS = Gem::Version.new("2.1")
+
+      alias_method :rg_required_ruby_version=, :required_ruby_version=
+      def required_ruby_version=(req)
+        self.rg_required_ruby_version = req
+
+        @required_ruby_version.requirements.map! do |op, v|
+          if v >= LATEST_RUBY_WITHOUT_PATCH_VERSIONS && v.release.segments.size == 4
+            [op == "~>" ? "=" : op, Gem::Version.new(v.segments.tap {|s| s.delete_at(3) }.join("."))]
+          else
+            [op, v]
+          end
+        end
+      end
+    end
+
     def groups
       @groups ||= []
     end
diff --git a/bundler/lib/bundler/source/metadata.rb b/bundler/lib/bundler/source/metadata.rb
index 524afd750a84..185fe7082474 100644
--- a/bundler/lib/bundler/source/metadata.rb
+++ b/bundler/lib/bundler/source/metadata.rb
@@ -5,7 +5,7 @@ class Source
     class Metadata < Source
       def specs
         @specs ||= Index.build do |idx|
-          idx << Gem::Specification.new("Ruby\0", RubyVersion.system.to_gem_version_with_patchlevel)
+          idx << Gem::Specification.new("Ruby\0", RubyVersion.system.gem_version)
           idx << Gem::Specification.new("RubyGems\0", Gem::VERSION) do |s|
             s.required_rubygems_version = Gem::Requirement.default
           end
diff --git a/bundler/spec/bundler/ruby_version_spec.rb b/bundler/spec/bundler/ruby_version_spec.rb
index 8c6c071d7f01..3e3850031c24 100644
--- a/bundler/spec/bundler/ruby_version_spec.rb
+++ b/bundler/spec/bundler/ruby_version_spec.rb
@@ -498,31 +498,5 @@
         end
       end
     end
-
-    describe "#to_gem_version_with_patchlevel" do
-      shared_examples_for "the patchlevel is omitted" do
-        it "does not include a patch level" do
-          expect(subject.to_gem_version_with_patchlevel.to_s).to eq(version)
-        end
-      end
-
-      context "with nil patch number" do
-        let(:patchlevel) { nil }
-
-        it_behaves_like "the patchlevel is omitted"
-      end
-
-      context "with negative patch number" do
-        let(:patchlevel) { -1 }
-
-        it_behaves_like "the patchlevel is omitted"
-      end
-
-      context "with a valid patch number" do
-        it "uses the specified patchlevel as patchlevel" do
-          expect(subject.to_gem_version_with_patchlevel.to_s).to eq("#{version}.#{patchlevel}")
-        end
-      end
-    end
   end
 end
diff --git a/bundler/spec/install/gems/resolving_spec.rb b/bundler/spec/install/gems/resolving_spec.rb
index 209996f61fde..21ecaad50e0f 100644
--- a/bundler/spec/install/gems/resolving_spec.rb
+++ b/bundler/spec/install/gems/resolving_spec.rb
@@ -301,7 +301,7 @@
       end
 
       let(:ruby_requirement) { %("#{RUBY_VERSION}") }
-      let(:error_message_requirement) { "~> #{RUBY_VERSION}.0" }
+      let(:error_message_requirement) { "= #{RUBY_VERSION}" }
 
       shared_examples_for "ruby version conflicts" do
         it "raises an error during resolution" do
diff --git a/lib/rubygems.rb b/lib/rubygems.rb
index d2c404d7d3f5..886b7167c485 100644
--- a/lib/rubygems.rb
+++ b/lib/rubygems.rb
@@ -864,9 +864,7 @@ def self.ruby_version
     return @ruby_version if defined? @ruby_version
     version = RUBY_VERSION.dup
 
-    if defined?(RUBY_PATCHLEVEL) && RUBY_PATCHLEVEL != -1
-      version << ".#{RUBY_PATCHLEVEL}"
-    elsif defined?(RUBY_DESCRIPTION)
+    if defined?(RUBY_DESCRIPTION)
       if RUBY_ENGINE == "ruby"
         desc = RUBY_DESCRIPTION[/\Aruby #{Regexp.quote(RUBY_VERSION)}([^ ]+) /, 1]
       else
diff --git a/lib/rubygems/specification.rb b/lib/rubygems/specification.rb
index 0d72cee51d5b..7e7599f7dbf9 100644
--- a/lib/rubygems/specification.rb
+++ b/lib/rubygems/specification.rb
@@ -657,6 +657,8 @@ def rdoc_options
     @rdoc_options ||= []
   end
 
+  LATEST_RUBY_WITHOUT_PATCH_VERSIONS = Gem::Version.new("2.1")
+
   ##
   # The version of Ruby required by this gem.  The ruby version can be
   # specified to the patch-level:
@@ -683,6 +685,14 @@ def rdoc_options
 
   def required_ruby_version=(req)
     @required_ruby_version = Gem::Requirement.create req
+
+    @required_ruby_version.requirements.map! do |op, v|
+      if v >= LATEST_RUBY_WITHOUT_PATCH_VERSIONS && v.release.segments.size == 4
+        [op == "~>" ? "=" : op, Gem::Version.new(v.segments.tap {|s| s.delete_at(3) }.join("."))]
+      else
+        [op, v]
+      end
+    end
   end
 
   ##
diff --git a/test/rubygems/test_gem.rb b/test/rubygems/test_gem.rb
index a8be07804660..df1c6e0e58ea 100644
--- a/test/rubygems/test_gem.rb
+++ b/test/rubygems/test_gem.rb
@@ -1114,14 +1114,6 @@ def test_self_ruby_version_with_patchlevel_less_ancient_rubies
     util_restore_RUBY_VERSION
   end
 
-  def test_self_ruby_version_with_release
-    util_set_RUBY_VERSION '1.8.6', 287
-
-    assert_equal Gem::Version.new('1.8.6.287'), Gem.ruby_version
-  ensure
-    util_restore_RUBY_VERSION
-  end
-
   def test_self_ruby_version_with_non_mri_implementations
     util_set_RUBY_VERSION '2.5.0', 0, 60928, 'jruby 9.2.0.0 (2.5.0) 2018-05-24 81156a8 OpenJDK 64-Bit Server VM 25.171-b11 on 1.8.0_171-8u171-b11-0ubuntu0.16.04.1-b11 [linux-x86_64]'