diff --git a/feature-policy/experimental-features/resources/feature-policy-vertical-scroll.html b/feature-policy/experimental-features/resources/feature-policy-vertical-scroll.html
new file mode 100644
index 00000000000000..2b8253850cf12d
--- /dev/null
+++ b/feature-policy/experimental-features/resources/feature-policy-vertical-scroll.html
@@ -0,0 +1,35 @@
+<!DOCTYPE html>
+<style>
+  html, body, div {
+    width: 100%;
+    height: 100%;
+    padding: 0;
+    margin: 0;
+    border: 0;
+  }
+  div {background-color: gold;}
+</style>
+<div>
+</div>
+<script>
+  const element = document.querySelector('div');
+  window.scroll_to_view = false;
+
+  function setup() {
+    var href = window.location.href;
+    var query = href.substring(href.indexOf("?q=") + 3);
+      switch (query) {
+        case "touchstart":
+        case "touchmove":
+        case "wheel":
+        element.addEventListener(query, (e) => { e.preventDefault(); });
+        break;
+      case "touchaction":
+        element.style.touchAction = "pan-x";
+        break;
+      case "script":
+        element.scrollIntoView({behavior: "instant"});
+    }
+  }
+  window.addEventListener("load", setup);
+</script>
diff --git a/feature-policy/experimental-features/resources/vertical_scroll_common.js b/feature-policy/experimental-features/resources/vertical_scroll_common.js
new file mode 100644
index 00000000000000..be026f12acbedb
--- /dev/null
+++ b/feature-policy/experimental-features/resources/vertical_scroll_common.js
@@ -0,0 +1,57 @@
+// Common method used in vertical scrolling tests.
+const same_origin_url = "/feature-policy/experimental-features/resources/feature-policy-vertical-scroll.html";
+const cross_origin_url = "https://{{domains[www]}}:{{ports[https][0]}}" + same_origin_url;
+const large_number = 1000000;
+const visible_rect = new DOMRect(0, 0, window.innerWidth, window.innerHeight);
+
+function rect_contains(rect, x, y) {
+  return (rect.left <= x)  && (rect.right >= x) &&
+         (rect.top <= y) && (rect.bottom >= y);
+}
+
+function rect_intersects(rect1, rect2) {
+  return rect_contains(rect1, rect2.left, rect2.top) ||
+         rect_contains(rect1, rect2.left, rect2.bottom) ||
+         rect_contains(rect1, rect2.right, rect2.top) ||
+         rect_contains(rect1, rect2.right, rect2.bottom);
+}
+
+function iframe() {
+  return document.querySelector("iframe");
+}
+
+// Returns a promise which is resolved when the <iframe> is navigated to |url|
+// and "load" handler has been called.
+function loadUrlInIframe(url) {
+  return new Promise((resolve) => {
+    iframe().addEventListener("load", resolve);
+    iframe().src = url;
+  });
+}
+
+// Returns a promise which is resolved as soon as "message" is received.
+function waitForMessage(message) {
+  return new Promise((resolve) => {
+    function handler(e) {
+      if (e.data !== message)
+        return;
+      window.removeEventListener("message", handler);
+      resolve();
+    }
+    window.addEventListener("message", handler);
+  });
+}
+
+// Returns a promise which is resolved when the testing API for input is loaded.
+function testAPIReady() {
+  return new Promise((resolve) => {
+    function checkForAPI() {
+      if (window.touchScrollDown) {
+        resolve();
+      } else {
+        step_timeout(checkForAPI);
+      }
+    }
+    checkForAPI();
+  });
+}
diff --git a/feature-policy/experimental-features/vertical-scroll-programmatic.sub.html b/feature-policy/experimental-features/vertical-scroll-programmatic.sub.html
new file mode 100644
index 00000000000000..b3eebe054bf1a3
--- /dev/null
+++ b/feature-policy/experimental-features/vertical-scroll-programmatic.sub.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/feature-policy/experimental-features/resources/vertical_scroll_common.js"></script>
+<style>
+html, body {
+  border: 0;
+  margin: 0;
+  padding: 0;
+  height: 100%;
+  width: 100%;
+}
+
+iframe {
+  width: 95%;
+  height: 95%;
+  border: solid 1px gold;
+  margin-left: 0px;
+  margin-top: 0px;
+}
+</style>
+<p> An &lt;iframe&gt; further below which is not allowed to block scroll.</p>
+<iframe></iframe>
+<p style="margin-top: 10000px"> Making sure there is room for vertical scroll </p>
+<script>
+  "use strict";
+
+  test(() => {
+    window.scrollTo(large_number, large_number);
+    assert_false(
+     rect_intersects(visible_rect, iframe().getBoundingClientRect()),
+     "<iframe> bounds are inside visible rect:" +
+     JSON.stringify(iframe().getBoundingClientRect().toJSON()));
+   iframe().contentDocument.body.scrollIntoView({behavior: "instant"});
+   assert_true(
+     rect_intersects(visible_rect, iframe().getBoundingClientRect()),
+     "<iframe> bounds are outside visible rect:" +
+     JSON.stringify(iframe().getBoundingClientRect().toJSON()));
+  }, "Sanity-check: element.scrollIntoView() works fine on this page.");
+
+  promise_test(async() => {
+    window.scrollTo(large_number, large_number);
+    await loadUrlInIframe(same_origin_url + "?q=script");
+    assert_true(
+      rect_intersects(visible_rect, iframe().getBoundingClientRect()),
+      "Expected the <iframe> to scroll into view but its bounds are: " +
+      JSON.stringify(iframe().getBoundingClientRect().toJSON()));
+  },
+ "Verify a same-origin frame can always scroll into view.");
+
+ promise_test(async() => {
+    window.scrollTo(large_number, large_number);
+    await loadUrlInIframe(cross_origin_url + "?q=script");
+    assert_false(
+      rect_intersects(visible_rect, iframe().getBoundingClientRect()),
+      "Expected the <iframe> not to scroll into view but its bounds are: " +
+      JSON.stringify(iframe().getBoundingClientRect().toJSON()));
+  },
+ "Verify a cross-origin frame cannot scroll into view.");
+</script>
diff --git a/feature-policy/experimental-features/vertical-scroll-touchaction-manual.sub.html b/feature-policy/experimental-features/vertical-scroll-touchaction-manual.sub.html
new file mode 100644
index 00000000000000..c66f4da5eef803
--- /dev/null
+++ b/feature-policy/experimental-features/vertical-scroll-touchaction-manual.sub.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/feature-policy/experimental-features/resources/vertical_scroll_common.js"></script>
+<style>
+html, body {
+  border: 0;
+  margin: 0;
+  padding: 0;
+  height: 100%;
+  width: 100%;
+}
+
+iframe {
+  width: 95%;
+  height: 95%;
+  border: solid 1px gold;
+  margin-left: 0px;
+  margin-top: 0px;
+}
+</style>
+<p> An &lt;iframe&gt; further below which is not allowed to block scroll.</p>
+<iframe></iframe>
+<p style="margin-top: 10000px"> Making sure there is room for vertical scroll </p>
+<script>
+  "use strict";
+
+    promise_test(async() => {
+      await testAPIReady();
+      window.scrollTo(0, 0);
+      await inject_input();
+      assert_greater_than(
+        document.scrollingElement.scrollTop,
+        0,
+        `scrollTop did not increase.`);
+    }, `Sanity-check: make sure page does scroll.` );
+
+    for (var url of [same_origin_url, cross_origin_url]) {
+      let same_origin = (url === same_origin_url);
+      promise_test(async(test_instance) => {
+        await testAPIReady();
+        let same_origin = test_instance.properties.same_origin;
+        window.scrollTo(0, 0);
+        let initial_scroll_top = document.scrollingElement.scrollTop;
+        await loadUrlInIframe(test_instance.properties.frame_url);
+        // Tap down inside the <iframe> and then apply a gesture scroll.
+        await inject_input();
+        let new_scroll_top = document.scrollingElement.scrollTop;
+        assert_equals(new_scroll_top > initial_scroll_top, !same_origin,
+          `Did ${same_origin ? "not" : ""} expect vertical scroll.` +
+          `(scrollTop changed from ${initial_scroll_top} to ${new_scroll_top}`);
+      },
+      `Verify that a ${same_origin ? "same" : "cross"}-origin frame can ` +
+      `${same_origin ? "" : "not "}block scrolling by canceling "touchaction".`,
+      {
+        "same_origin": same_origin,
+        "frame_url": `${url}?q=touchaction`,
+      });
+    }
+  </script>
diff --git a/feature-policy/experimental-features/vertical-scroll-touchmove-manual.sub.html b/feature-policy/experimental-features/vertical-scroll-touchmove-manual.sub.html
new file mode 100644
index 00000000000000..310aa66e0fe0b7
--- /dev/null
+++ b/feature-policy/experimental-features/vertical-scroll-touchmove-manual.sub.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/feature-policy/experimental-features/resources/vertical_scroll_common.js"></script>
+<style>
+html, body {
+  border: 0;
+  margin: 0;
+  padding: 0;
+  height: 100%;
+  width: 100%;
+}
+
+iframe {
+  width: 95%;
+  height: 95%;
+  border: solid 1px gold;
+  margin-left: 0px;
+  margin-top: 0px;
+}
+</style>
+<p> An &lt;iframe&gt; further below which is not allowed to block scroll.</p>
+<iframe></iframe>
+<p style="margin-top: 10000px"> Making sure there is room for vertical scroll </p>
+<script>
+  "use strict";
+
+    promise_test(async() => {
+      await testAPIReady();
+      window.scrollTo(0, 0);
+      await inject_input();
+      assert_greater_than(
+        document.scrollingElement.scrollTop,
+        0,
+        `scrollTop did not increase.`);
+    }, `Sanity-check: make sure page does scroll.` );
+
+    for (var url of [same_origin_url, cross_origin_url]) {
+      let same_origin = (url === same_origin_url);
+      promise_test(async(test_instance) => {
+        await testAPIReady();
+        let same_origin = test_instance.properties.same_origin;
+        window.scrollTo(0, 0);
+        let initial_scroll_top = document.scrollingElement.scrollTop;
+        await loadUrlInIframe(test_instance.properties.frame_url);
+        // Tap down inside the <iframe> and then apply a gesture scroll.
+        await inject_input();
+        let new_scroll_top = document.scrollingElement.scrollTop;
+        assert_equals(new_scroll_top > initial_scroll_top, !same_origin,
+          `Did ${same_origin ? "not" : ""} expect vertical scroll.` +
+          `(scrollTop changed from ${initial_scroll_top} to ${new_scroll_top}`);
+      },
+      `Verify that a ${same_origin ? "same" : "cross"}-origin frame can ` +
+      `${same_origin ? "" : "not "}block scrolling by canceling "touchmove".`,
+      {
+        "same_origin": same_origin,
+        "frame_url": `${url}?q=touchmove`,
+      });
+    }
+  </script>
diff --git a/feature-policy/experimental-features/vertical-scroll-touchstart-manual.sub.html b/feature-policy/experimental-features/vertical-scroll-touchstart-manual.sub.html
new file mode 100644
index 00000000000000..a1512e8b567dee
--- /dev/null
+++ b/feature-policy/experimental-features/vertical-scroll-touchstart-manual.sub.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/feature-policy/experimental-features/resources/vertical_scroll_common.js"></script>
+<style>
+html, body {
+  border: 0;
+  margin: 0;
+  padding: 0;
+  height: 100%;
+  width: 100%;
+}
+
+iframe {
+  width: 95%;
+  height: 95%;
+  border: solid 1px gold;
+  margin-left: 0px;
+  margin-top: 0px;
+}
+</style>
+<p> An &lt;iframe&gt; further below which is not allowed to block scroll.</p>
+<iframe></iframe>
+<p style="margin-top: 10000px"> Making sure there is room for vertical scroll </p>
+<script>
+  "use strict";
+
+    promise_test(async() => {
+      await testAPIReady();
+      window.scrollTo(0, 0);
+      await inject_input();
+      assert_greater_than(
+        document.scrollingElement.scrollTop,
+        0,
+        `scrollTop did not increase.`);
+    }, `Sanity-check: make sure page does scroll.` );
+
+    for (var url of [same_origin_url, cross_origin_url]) {
+      let same_origin = (url === same_origin_url);
+      promise_test(async(test_instance) => {
+        await testAPIReady();
+        let same_origin = test_instance.properties.same_origin;
+        window.scrollTo(0, 0);
+        let initial_scroll_top = document.scrollingElement.scrollTop;
+        await loadUrlInIframe(test_instance.properties.frame_url);
+        // Tap down inside the <iframe> and then apply a gesture scroll.
+        await inject_input();
+        let new_scroll_top = document.scrollingElement.scrollTop;
+        assert_equals(new_scroll_top > initial_scroll_top, !same_origin,
+          `Did ${same_origin ? "not" : ""} expect vertical scroll.` +
+          `(scrollTop changed from ${initial_scroll_top} to ${new_scroll_top}`);
+      },
+      `Verify that a ${same_origin ? "same" : "cross"}-origin frame can ` +
+      `${same_origin ? "" : "not "}block scrolling by canceling "touchstart".`,
+      {
+        "same_origin": same_origin,
+        "frame_url": `${url}?q=touchstart`,
+      });
+    }
+  </script>
