diff --git a/tests/test_formdata.py b/tests/test_formdata.py
index 436073b4f..0bb4ed684 100644
--- a/tests/test_formdata.py
+++ b/tests/test_formdata.py
@@ -217,9 +217,17 @@ def test_file_field(pub, formdef):
 
 
 def test_get_submitter(pub, formdef):
+    BlockDef.wipe()
+    block = BlockDef()
+    block.name = 'foobar'
+    block.fields = [
+        fields.StringField(id='0', label='email', varname='foo', prefill={'type': 'user', 'value': 'email'})
+    ]
+    block.store()
     formdef.data_class().wipe()
     formdef.fields = [
-        fields.StringField(id='0', label='email', varname='foo', prefill={'type': 'user', 'value': 'email'})
+        fields.StringField(id='0', label='email', varname='foo', prefill={'type': 'user', 'value': 'email'}),
+        fields.BlockField(id='1', label='test', type='block:foobar', max_items=3, varname='block'),
     ]
     formdef.store()
 
@@ -228,6 +236,42 @@ def test_get_submitter(pub, formdef):
     formdata.data = {'0': 'foo@localhost'}
     assert formdef.get_submitter_email(formdata) == 'foo@localhost'
 
+    formdata.data = {
+        '1': {
+            'data': [{'0': 'baz@localhost'}, {'0': ''}],
+            'schema': {'0': 'string'},
+        }
+    }
+    assert formdef.get_submitter_email(formdata) == 'baz@localhost'
+
+    formdata.data = {
+        '1': {
+            'data': [{'0': 'baz@localhost'}, {'0': 'foo@localhost'}],
+            'schema': {'0': 'string'},
+        }
+    }
+    assert formdef.get_submitter_email(formdata) == 'baz@localhost'
+
+    formdata.data = {
+        '1': {
+            'data': [{'0': ''}, {'0': 'foo@localhost'}],
+            'schema': {'0': 'string'},
+        }
+    }
+    assert formdef.get_submitter_email(formdata) == 'foo@localhost'
+
+    formdata.data = {'1': {}}
+    assert formdef.get_submitter_email(formdata) is None
+
+    formdata.data = {
+        '0': 'foo@localhost',
+        '1': {
+            'data': [{'0': 'baz@localhost'}, {'0': ''}],
+            'schema': {'0': 'string'},
+        },
+    }
+    assert formdef.get_submitter_email(formdata) == 'foo@localhost'
+
     user = pub.user_class()
     user.email = 'bar@localhost'
     user.store()
diff --git a/wcs/formdef.py b/wcs/formdef.py
index a66c2dfdc..3658e94fb 100644
--- a/wcs/formdef.py
+++ b/wcs/formdef.py
@@ -1324,16 +1324,40 @@ class FormDef(StorableObject):
 
         # look up in submitted form for one that would hold the user
         # email (the one set to be prefilled by user email)
+
+        def is_user_field(field):
+            if not getattr(field, 'prefill', None):
+                return False
+            if field.prefill.get('type') != 'user':
+                return False
+            if field.prefill.get('value') != field_email:
+                return False
+            return True
+
         if formdata.data:
-            fields = formdata.formdef.fields
-            for field in fields:
-                if not hasattr(field, 'prefill'):
+            # check first in "normal" fields
+            for field in formdata.formdef.fields:
+                if not is_user_field(field):
                     continue
-                if field.prefill and field.prefill.get('type') == 'user':
-                    if field.prefill.get('value') == field_email:
-                        v = formdata.data.get(field.id)
-                        if v:
-                            return v
+
+                v = formdata.data.get(field.id)
+                if v:
+                    return v
+
+            # then check in block fields
+            for field in formdata.formdef.fields:
+                if field.key != 'block':
+                    continue
+                for subfield in field.block.fields:
+                    if not is_user_field(subfield):
+                        continue
+                    v = formdata.data.get(field.id)
+                    if not v.get('data'):
+                        continue
+                    for data in v.get('data'):
+                        w = data.get(subfield.id)
+                        if w:
+                            return w
 
         # if nothing was found, get email from user profile
         if formdata.user and formdata.user.email and formdata.user.is_active: