diff --git a/service-workers/service-worker/multi-globals/current/current.https.html b/service-workers/service-worker/multi-globals/current/current.https.html
new file mode 100644
index 00000000000000..82a48d409901b4
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/current/current.https.html
@@ -0,0 +1,2 @@
+<!DOCTYPE html>
+<title>Current page used as a test helper</title>
diff --git a/service-workers/service-worker/multi-globals/current/test-sw.js b/service-workers/service-worker/multi-globals/current/test-sw.js
new file mode 100644
index 00000000000000..ca340943068c2b
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/current/test-sw.js
@@ -0,0 +1,15 @@
+'use strict';
+
+this.addEventListener('install', event => {
+    this.skipWaiting();
+});
+
+this.addEventListener('activate', event => {
+    clients.claim();
+});
+
+this.addEventListener('fetch', event => {
+    if (event.request.url.includes('test.txt')) {
+        event.respondWith(new Response('current'));
+    }
+});
diff --git a/service-workers/service-worker/multi-globals/incumbent/incumbent.https.html b/service-workers/service-worker/multi-globals/incumbent/incumbent.https.html
new file mode 100644
index 00000000000000..4585f15b0f45d0
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/incumbent/incumbent.https.html
@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<title>Incumbent page used as a test helper</title>
+
+<iframe src="../current/current.https.html" id="c"></iframe>
+<iframe src="../relevant/relevant.https.html" id="r"></iframe>
+
+<script>
+'use strict';
+
+const current = document.querySelector('#c').contentWindow;
+const relevant = document.querySelector('#r').contentWindow;
+
+window.testRegister = options => {
+    return current.navigator.serviceWorker.register.call(relevant.navigator.serviceWorker, 'test-sw.js', options);
+};
+
+window.testGetRegistration = () => {
+    return current.navigator.serviceWorker.getRegistration.call(relevant.navigator.serviceWorker, 'test-sw.js');
+};
+</script>
diff --git a/service-workers/service-worker/multi-globals/incumbent/test-sw.js b/service-workers/service-worker/multi-globals/incumbent/test-sw.js
new file mode 100644
index 00000000000000..2f970a25ce6609
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/incumbent/test-sw.js
@@ -0,0 +1,15 @@
+'use strict';
+
+this.addEventListener('install', event => {
+    this.skipWaiting();
+});
+
+this.addEventListener('activate', event => {
+    clients.claim();
+});
+
+this.addEventListener('fetch', event => {
+    if (event.request.url.includes('test.txt')) {
+        event.respondWith(new Response('incumbent'));
+    }
+});
diff --git a/service-workers/service-worker/multi-globals/relevant/relevant.https.html b/service-workers/service-worker/multi-globals/relevant/relevant.https.html
new file mode 100644
index 00000000000000..44f42eda493c27
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/relevant/relevant.https.html
@@ -0,0 +1,2 @@
+<!DOCTYPE html>
+<title>Relevant page used as a test helper</title>
diff --git a/service-workers/service-worker/multi-globals/relevant/test-sw.js b/service-workers/service-worker/multi-globals/relevant/test-sw.js
new file mode 100644
index 00000000000000..3cf80c54cb0ad1
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/relevant/test-sw.js
@@ -0,0 +1,15 @@
+'use strict';
+
+this.addEventListener('install', event => {
+    this.skipWaiting();
+});
+
+this.addEventListener('activate', event => {
+    clients.claim();
+});
+
+this.addEventListener('fetch', event => {
+    if (event.request.url.includes('test.txt')) {
+        event.respondWith(new Response('relevant'));
+    }
+});
diff --git a/service-workers/service-worker/multi-globals/test-sw.js b/service-workers/service-worker/multi-globals/test-sw.js
new file mode 100644
index 00000000000000..f5a6cc5f9dc880
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/test-sw.js
@@ -0,0 +1,15 @@
+'use strict';
+
+this.addEventListener('install', event => {
+    this.skipWaiting();
+});
+
+this.addEventListener('activate', event => {
+    clients.claim();
+});
+
+this.addEventListener('fetch', event => {
+    if (event.request.url.includes('test.txt')) {
+        event.respondWith(new Response('entry'));
+    }
+});
diff --git a/service-workers/service-worker/multi-globals/url-parsing.https.html b/service-workers/service-worker/multi-globals/url-parsing.https.html
new file mode 100644
index 00000000000000..1330d07805bb85
--- /dev/null
+++ b/service-workers/service-worker/multi-globals/url-parsing.https.html
@@ -0,0 +1,72 @@
+<!DOCTYPE html>
+<title>register()/getRegistration() URL parsing, with multiple globals in play</title>
+<link rel="help" href="https://w3c.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-container-register-method">
+<link rel="help" href="https://w3c.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-container-getregistration-method">
+<link rel="author" title="Domenic Denicola" href="mailto:d@domenic.me">
+<script src="/resources/testharness.js"></script>
+<script src="../resources/testharness-helpers.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../resources/test-helpers.sub.js"></script>
+
+<!-- This is the entry global -->
+
+<iframe src="incumbent/incumbent.https.html"></iframe>
+
+<script>
+'use strict';
+
+const loadPromise = new Promise(resolve => {
+    window.addEventListener('load', () => resolve());
+});
+
+promise_test(t => {
+    let registration;
+
+    return loadPromise.then(() => {
+        return frames[0].testRegister();
+    }).then(r => {
+        registration = r;
+        const newestWorker = r.installing || r.waiting || r.active;
+        return wait_for_state(t, newestWorker, 'activated');
+    }).then(() => {
+        return fetch('relevant/test.txt');
+    })
+    .then(response => response.text())
+    .then(text => {
+        assert_equals(text, 'relevant',
+            'the service worker found at relevant/test-sw.js must have been the one to intercept the fetch');
+
+        return registration.unregister();
+    });
+}, 'register should use the relevant global of the object it was called on to resolve the script URL');
+
+promise_test(t => {
+    return loadPromise.then(() => {
+        return frames[0].testRegister({ scope: 'scope' });
+    }).then(registration => {
+        assert_equals(registration.scope, normalizeURL('relevant/scope'), 'the scope URL should be relevant/scope');
+
+        return registration.unregister();
+    });
+}, 'register should use the relevant global of the object it was called on to resolve the scope URL');
+
+promise_test(t => {
+    let registration;
+
+    return loadPromise.then(() => {
+        return navigator.serviceWorker.register(normalizeURL('relevant/test-sw.js'));
+    }).then(r => {
+        registration = r;
+        return frames[0].testGetRegistration();
+    })
+    .then(gottenRegistration => {
+        assert_not_equals(registration, null, 'the registration should not be null');
+        assert_not_equals(gottenRegistration, null, 'the registration from the other frame should not be null');
+        assert_equals(gottenRegistration.scope, registration.scope,
+            'the retrieved registration\'s scope should be equal to the original\'s scope');
+
+        return registration.unregister();
+    });
+}, 'getRegistration should use the relevant global of the object it was called on to resolve the script URL');
+
+</script>
