diff --git a/tests/fixtures/config/pragma-multibranch/git/common-config/zuul.yaml b/tests/fixtures/config/pragma-multibranch/git/common-config/zuul.yaml
new file mode 100644
index 0000000..dc83f9d
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/git/common-config/zuul.yaml
@@ -0,0 +1,61 @@
+- pipeline:
+    name: check
+    manager: independent
+    trigger:
+      gerrit:
+        - event: patchset-created
+    success:
+      gerrit:
+        Verified: 1
+    failure:
+      gerrit:
+        Verified: -1
+
+- pipeline:
+    name: gate
+    manager: dependent
+    post-review: True
+    trigger:
+      gerrit:
+        - event: comment-added
+          approval:
+            - Approved: 1
+    success:
+      gerrit:
+        Verified: 2
+        submit: true
+    failure:
+      gerrit:
+        Verified: -2
+    start:
+      gerrit:
+        Verified: 0
+    precedence: high
+
+- job:
+    name: base
+    parent: null
+
+- project:
+    name: common-config
+    check:
+      jobs: []
+    gate:
+      jobs:
+        - noop
+
+- project:
+    name: org/project1
+    check:
+      jobs: []
+    gate:
+      jobs:
+        - noop
+
+- project:
+    name: org/project2
+    check:
+      jobs: []
+    gate:
+      jobs:
+        - noop
diff --git a/tests/fixtures/config/pragma-multibranch/git/org_project1/README b/tests/fixtures/config/pragma-multibranch/git/org_project1/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/git/org_project1/README
@@ -0,0 +1 @@
+test
diff --git a/tests/fixtures/config/pragma-multibranch/git/org_project1/playbooks/test-job1.yaml b/tests/fixtures/config/pragma-multibranch/git/org_project1/playbooks/test-job1.yaml
new file mode 100644
index 0000000..f679dce
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/git/org_project1/playbooks/test-job1.yaml
@@ -0,0 +1,2 @@
+- hosts: all
+  tasks: []
diff --git a/tests/fixtures/config/pragma-multibranch/git/org_project1/playbooks/test-job2.yaml b/tests/fixtures/config/pragma-multibranch/git/org_project1/playbooks/test-job2.yaml
new file mode 100644
index 0000000..f679dce
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/git/org_project1/playbooks/test-job2.yaml
@@ -0,0 +1,2 @@
+- hosts: all
+  tasks: []
diff --git a/tests/fixtures/config/pragma-multibranch/git/org_project1/zuul.yaml b/tests/fixtures/config/pragma-multibranch/git/org_project1/zuul.yaml
new file mode 100644
index 0000000..6c8352a
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/git/org_project1/zuul.yaml
@@ -0,0 +1,13 @@
+- job:
+    name: test-job1
+    run: playbooks/test-job1.yaml
+
+- job:
+    name: test-job2
+    run: playbooks/test-job2.yaml
+
+- project-template:
+    name: test-template
+    check:
+      jobs:
+        - test-job1
diff --git a/tests/fixtures/config/pragma-multibranch/git/org_project2/README b/tests/fixtures/config/pragma-multibranch/git/org_project2/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/git/org_project2/README
@@ -0,0 +1 @@
+test
diff --git a/tests/fixtures/config/pragma-multibranch/git/org_project2/zuul.yaml b/tests/fixtures/config/pragma-multibranch/git/org_project2/zuul.yaml
new file mode 100644
index 0000000..748cab2
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/git/org_project2/zuul.yaml
@@ -0,0 +1,7 @@
+- project:
+    name: org/project2
+    templates:
+      - test-template
+    check:
+      jobs:
+        - test-job2
diff --git a/tests/fixtures/config/pragma-multibranch/main.yaml b/tests/fixtures/config/pragma-multibranch/main.yaml
new file mode 100644
index 0000000..950b117
--- /dev/null
+++ b/tests/fixtures/config/pragma-multibranch/main.yaml
@@ -0,0 +1,9 @@
+- tenant:
+    name: tenant-one
+    source:
+      gerrit:
+        config-projects:
+          - common-config
+        untrusted-projects:
+          - org/project1
+          - org/project2
diff --git a/tests/unit/test_v3.py b/tests/unit/test_v3.py
index 1f401d0..e4ef619 100755
--- a/tests/unit/test_v3.py
+++ b/tests/unit/test_v3.py
@@ -2232,6 +2232,115 @@
             self.assertIsNone(job.branch_matcher)
 
 
+class TestPragmaMultibranch(ZuulTestCase):
+    tenant_config_file = 'config/pragma-multibranch/main.yaml'
+
+    def test_no_branch_matchers(self):
+        self.create_branch('org/project1', 'stable/pike')
+        self.create_branch('org/project2', 'stable/jewel')
+        self.fake_gerrit.addEvent(
+            self.fake_gerrit.getFakeBranchCreatedEvent(
+                'org/project1', 'stable/pike'))
+        self.fake_gerrit.addEvent(
+            self.fake_gerrit.getFakeBranchCreatedEvent(
+                'org/project2', 'stable/jewel'))
+        self.waitUntilSettled()
+        # We want the jobs defined on the stable/pike branch of
+        # project1 to apply to the stable/jewel branch of project2.
+
+        # First, without the pragma line, the jobs should not run
+        # because in project1 they have branch matchers for pike, so
+        # they will not match a jewel change.
+        B = self.fake_gerrit.addFakeChange('org/project2', 'stable/jewel', 'B')
+        self.fake_gerrit.addEvent(B.getPatchsetCreatedEvent(1))
+        self.waitUntilSettled()
+        self.assertHistory([])
+
+        # Add a pragma line to disable implied branch matchers in
+        # project1, so that the jobs and templates apply to both
+        # branches.
+        with open(os.path.join(FIXTURE_DIR,
+                               'config/pragma-multibranch/git/',
+                               'org_project1/zuul.yaml')) as f:
+            config = f.read()
+        extra_conf = textwrap.dedent(
+            """
+            - pragma:
+                implied-branch-matchers: False
+            """)
+        config = extra_conf + config
+        file_dict = {'zuul.yaml': config}
+        A = self.fake_gerrit.addFakeChange('org/project1', 'stable/pike', 'A',
+                                           files=file_dict)
+        A.addApproval('Code-Review', 2)
+        self.fake_gerrit.addEvent(A.addApproval('Approved', 1))
+        self.waitUntilSettled()
+        self.fake_gerrit.addEvent(A.getChangeMergedEvent())
+        self.waitUntilSettled()
+
+        # Now verify that when we propose a change to jewel, we get
+        # the pike/jewel jobs.
+        self.fake_gerrit.addEvent(B.getPatchsetCreatedEvent(1))
+        self.waitUntilSettled()
+        self.assertHistory([
+            dict(name='test-job1', result='SUCCESS', changes='1,1'),
+            dict(name='test-job2', result='SUCCESS', changes='1,1'),
+        ], ordered=False)
+
+    def test_supplied_branch_matchers(self):
+        self.create_branch('org/project1', 'stable/pike')
+        self.create_branch('org/project2', 'stable/jewel')
+        self.fake_gerrit.addEvent(
+            self.fake_gerrit.getFakeBranchCreatedEvent(
+                'org/project1', 'stable/pike'))
+        self.fake_gerrit.addEvent(
+            self.fake_gerrit.getFakeBranchCreatedEvent(
+                'org/project2', 'stable/jewel'))
+        self.waitUntilSettled()
+        # We want the jobs defined on the stable/pike branch of
+        # project1 to apply to the stable/jewel branch of project2.
+
+        # First, without the pragma line, the jobs should not run
+        # because in project1 they have branch matchers for pike, so
+        # they will not match a jewel change.
+        B = self.fake_gerrit.addFakeChange('org/project2', 'stable/jewel', 'B')
+        self.fake_gerrit.addEvent(B.getPatchsetCreatedEvent(1))
+        self.waitUntilSettled()
+        self.assertHistory([])
+
+        # Add a pragma line to disable implied branch matchers in
+        # project1, so that the jobs and templates apply to both
+        # branches.
+        with open(os.path.join(FIXTURE_DIR,
+                               'config/pragma-multibranch/git/',
+                               'org_project1/zuul.yaml')) as f:
+            config = f.read()
+        extra_conf = textwrap.dedent(
+            """
+            - pragma:
+                implied-branches:
+                  - stable/pike
+                  - stable/jewel
+            """)
+        config = extra_conf + config
+        file_dict = {'zuul.yaml': config}
+        A = self.fake_gerrit.addFakeChange('org/project1', 'stable/pike', 'A',
+                                           files=file_dict)
+        A.addApproval('Code-Review', 2)
+        self.fake_gerrit.addEvent(A.addApproval('Approved', 1))
+        self.waitUntilSettled()
+        self.fake_gerrit.addEvent(A.getChangeMergedEvent())
+        self.waitUntilSettled()
+        # Now verify that when we propose a change to jewel, we get
+        # the pike/jewel jobs.
+        self.fake_gerrit.addEvent(B.getPatchsetCreatedEvent(1))
+        self.waitUntilSettled()
+        self.assertHistory([
+            dict(name='test-job1', result='SUCCESS', changes='1,1'),
+            dict(name='test-job2', result='SUCCESS', changes='1,1'),
+        ], ordered=False)
+
+
 class TestBaseJobs(ZuulTestCase):
     tenant_config_file = 'config/base-jobs/main.yaml'