diff --git a/media/base/videocapturer.cc b/media/base/videocapturer.cc
index 4147da79dd..a03f903c4c 100644
--- a/media/base/videocapturer.cc
+++ b/media/base/videocapturer.cc
@@ -179,7 +179,7 @@ bool VideoCapturer::AdaptFrame(int width,
   }
 
   bool simulcast_screenshare_enabled =
-      webrtc::field_trial::IsEnabled(kSimulcastScreenshareFieldTrialName);
+      !webrtc::field_trial::IsDisabled(kSimulcastScreenshareFieldTrialName);
   if (enable_video_adapter_ &&
       (!IsScreencast() || simulcast_screenshare_enabled)) {
     if (!video_adapter_.AdaptFrameResolution(
diff --git a/media/engine/simulcast.cc b/media/engine/simulcast.cc
index b2bc6e6d75..f1b3a3422c 100644
--- a/media/engine/simulcast.cc
+++ b/media/engine/simulcast.cc
@@ -345,7 +345,7 @@ std::vector<webrtc::VideoStream> GetScreenshareLayers(
 }
 
 bool ScreenshareSimulcastFieldTrialEnabled() {
-  return webrtc::field_trial::IsEnabled(kSimulcastScreenshareFieldTrialName);
+  return !webrtc::field_trial::IsDisabled(kSimulcastScreenshareFieldTrialName);
 }
 
 }  // namespace cricket
diff --git a/media/engine/simulcast_unittest.cc b/media/engine/simulcast_unittest.cc
index f36ac035e0..87aea61fc0 100644
--- a/media/engine/simulcast_unittest.cc
+++ b/media/engine/simulcast_unittest.cc
@@ -135,6 +135,8 @@ TEST(SimulcastTest, GetConfigWithNormalizedResolution) {
 }
 
 TEST(SimulcastTest, GetConfigForScreenshare) {
+  test::ScopedFieldTrials field_trials("WebRTC-SimulcastScreenshare/Disabled/");
+
   const size_t kMaxLayers = 3;
   std::vector<VideoStream> streams = cricket::GetSimulcastConfig(
       kMaxLayers, 1400, 800, kMaxBitrateBps, kBitratePriority, kQpMax, kMaxFps,
@@ -154,8 +156,6 @@ TEST(SimulcastTest, GetConfigForScreenshare) {
 }
 
 TEST(SimulcastTest, GetConfigForScreenshareSimulcast) {
-  test::ScopedFieldTrials field_trials("WebRTC-SimulcastScreenshare/Enabled/");
-
   const size_t kMaxLayers = 3;
   std::vector<VideoStream> streams = cricket::GetSimulcastConfig(
       kMaxLayers, 1400, 800, kMaxBitrateBps, kBitratePriority, kQpMax, kMaxFps,
diff --git a/media/engine/webrtcvideoengine_unittest.cc b/media/engine/webrtcvideoengine_unittest.cc
index 4373ec2686..1d56bffa27 100644
--- a/media/engine/webrtcvideoengine_unittest.cc
+++ b/media/engine/webrtcvideoengine_unittest.cc
@@ -6415,28 +6415,32 @@ TEST_F(WebRtcVideoChannelSimulcastTest, SetSendCodecsWithOddSizeInSimulcast) {
                           true);
 }
 
+// TODO(ilnik): Remove this test once Simulcast Screenshare is launched.
 TEST_F(WebRtcVideoChannelSimulcastTest, SetSendCodecsForScreenshare) {
+  webrtc::test::ScopedFieldTrials override_field_trials_(
+      "WebRTC-SimulcastScreenshare/Disabled/");
+
   VerifySimulcastSettings(cricket::VideoCodec("VP8"), 1280, 720, 3, 1, true,
                           false);
 }
 
+// TODO(ilnik): Remove this test once Simulcast Screenshare is launched.
 TEST_F(WebRtcVideoChannelSimulcastTest,
        SetSendCodecsForConferenceModeScreenshare) {
+  webrtc::test::ScopedFieldTrials override_field_trials_(
+      "WebRTC-SimulcastScreenshare/Disabled/");
+
   VerifySimulcastSettings(cricket::VideoCodec("VP8"), 1280, 720, 3, 1, true,
                           true);
 }
 
 TEST_F(WebRtcVideoChannelSimulcastTest, SetSendCodecsForSimulcastScreenshare) {
-  webrtc::test::ScopedFieldTrials override_field_trials_(
-      "WebRTC-SimulcastScreenshare/Enabled/");
   VerifySimulcastSettings(cricket::VideoCodec("VP8"), 1280, 720, 3, 2, true,
                           true);
 }
 
 TEST_F(WebRtcVideoChannelSimulcastTest,
        NoSimulcastScreenshareWithoutConference) {
-  webrtc::test::ScopedFieldTrials override_field_trials_(
-      "WebRTC-SimulcastScreenshare/Enabled/");
   VerifySimulcastSettings(cricket::VideoCodec("VP8"), 1280, 720, 3, 1, true,
                           false);
 }
diff --git a/video/full_stack_tests.cc b/video/full_stack_tests.cc
index 89af5be8bd..d43e53cb23 100644
--- a/video/full_stack_tests.cc
+++ b/video/full_stack_tests.cc
@@ -47,8 +47,8 @@ namespace webrtc {
 
 namespace {
 static const int kFullStackTestDurationSecs = 45;
-const char kScreenshareSimulcastExperiment[] =
-    "WebRTC-SimulcastScreenshare/Enabled/";
+const char kNotScreenshareSimulcastExperiment[] =
+    "WebRTC-SimulcastScreenshare/Disabled/";
 const char kRoundRobinPacingQueueExperiment[] =
     "WebRTC-RoundRobinPacing/Enabled/";
 const char kPacerPushBackExperiment[] =
@@ -594,6 +594,7 @@ TEST(FullStackTest, ConferenceMotionHd2000kbps100msLimitedQueueVP9) {
 #endif
 
 TEST(FullStackTest, ScreenshareSlidesVP8_2TL) {
+  test::ScopedFieldTrials field_trial(kNotScreenshareSimulcastExperiment);
   auto fixture = CreateVideoQualityTestFixture();
   ParamsWithLogging screenshare;
   screenshare.call.send_side_bwe = true;
@@ -608,7 +609,6 @@ TEST(FullStackTest, ScreenshareSlidesVP8_2TL) {
 
 TEST(FullStackTest, ScreenshareSlidesVP8_3TL_Simulcast) {
   auto fixture = CreateVideoQualityTestFixture();
-  test::ScopedFieldTrials field_trial(kScreenshareSimulcastExperiment);
   ParamsWithLogging screenshare;
   screenshare.call.send_side_bwe = true;
   screenshare.screenshare[0] = {true, false, 10};
@@ -636,6 +636,8 @@ TEST(FullStackTest, ScreenshareSlidesVP8_3TL_Simulcast) {
 }
 
 TEST(FullStackTest, ScreenshareSlidesVP8_2TL_Scroll) {
+  test::ScopedFieldTrials field_trial(kNotScreenshareSimulcastExperiment);
+
   auto fixture = CreateVideoQualityTestFixture();
   ParamsWithLogging config;
   config.call.send_side_bwe = true;
@@ -649,6 +651,8 @@ TEST(FullStackTest, ScreenshareSlidesVP8_2TL_Scroll) {
 }
 
 TEST(FullStackTest, ScreenshareSlidesVP8_2TL_LossyNet) {
+  test::ScopedFieldTrials field_trial(kNotScreenshareSimulcastExperiment);
+
   auto fixture = CreateVideoQualityTestFixture();
   ParamsWithLogging screenshare;
   screenshare.call.send_side_bwe = true;
@@ -665,6 +669,8 @@ TEST(FullStackTest, ScreenshareSlidesVP8_2TL_LossyNet) {
 }
 
 TEST(FullStackTest, ScreenshareSlidesVP8_2TL_VeryLossyNet) {
+  test::ScopedFieldTrials field_trial(kNotScreenshareSimulcastExperiment);
+
   auto fixture = CreateVideoQualityTestFixture();
   ParamsWithLogging screenshare;
   screenshare.call.send_side_bwe = true;
@@ -681,6 +687,8 @@ TEST(FullStackTest, ScreenshareSlidesVP8_2TL_VeryLossyNet) {
 }
 
 TEST(FullStackTest, ScreenshareSlidesVP8_2TL_LossyNetRestrictedQueue) {
+  test::ScopedFieldTrials field_trial(kNotScreenshareSimulcastExperiment);
+
   auto fixture = CreateVideoQualityTestFixture();
   ParamsWithLogging screenshare;
   screenshare.call.send_side_bwe = true;
@@ -698,6 +706,8 @@ TEST(FullStackTest, ScreenshareSlidesVP8_2TL_LossyNetRestrictedQueue) {
 }
 
 TEST(FullStackTest, ScreenshareSlidesVP8_2TL_ModeratelyRestricted) {
+  test::ScopedFieldTrials field_trial(kNotScreenshareSimulcastExperiment);
+
   auto fixture = CreateVideoQualityTestFixture();
   ParamsWithLogging screenshare;
   screenshare.call.send_side_bwe = true;
@@ -1057,7 +1067,6 @@ class DualStreamsTest : public ::testing::TestWithParam<int> {};
 TEST_P(DualStreamsTest,
        ModeratelyRestricted_SlidesVp8_3TL_Simulcast_Video_Simulcast_High) {
   test::ScopedFieldTrials field_trial(
-      std::string(kScreenshareSimulcastExperiment) +
       std::string(kRoundRobinPacingQueueExperiment) +
       std::string(kPacerPushBackExperiment));
   const int first_stream = GetParam();