diff --git a/kraken/serialization.py b/kraken/serialization.py
index e374eeafb..9666e344c 100644
--- a/kraken/serialization.py
+++ b/kraken/serialization.py
@@ -152,8 +152,8 @@ def serialize(results: 'Segmentation',
             reg = reg_dict[record.regions[0]]
             regs_with_lines.add(reg.id)
             region = {'id': reg.id,
-                      'bbox': max_bbox([reg.boundary]),
-                      'boundary': [list(x) for x in reg.boundary],
+                      'bbox': max_bbox([reg.boundary]) if reg.boundary else [],
+                      'boundary': [list(x) for x in reg.boundary] if reg.boundary else [],
                       'tags': reg.tags,
                       'lines': [],
                       'type': 'region'
diff --git a/kraken/templates/alto b/kraken/templates/alto
index ceed78733..9b8f45efb 100644
--- a/kraken/templates/alto
+++ b/kraken/templates/alto
@@ -107,7 +107,7 @@
                 {% if loop.previtem and loop.previtem.type == 'line' %}
                 </TextBlock>
                 {% endif %}
-                <TextBlock ID="{{ entity.id }}" HPOS="{{ entity.bbox[0] }}" VPOS="{{ entity.bbox[1] }}" WIDTH="{{ entity.bbox[2] - entity.bbox[0] }}" HEIGHT="{{ entity.bbox[3] - entity.bbox[1] }}" {% if entity.tags %}{% for type in page.region_types %}{% if type in entity.tags.values() %}TAGREFS="REGION_TYPE_{{ loop.index }}"{% endif %}{% endfor %}{% endif %}>
+                <TextBlock ID="{{ entity.id }}" {% if entity.bbox %}HPOS="{{ entity.bbox[0] }}" VPOS="{{ entity.bbox[1] }}" WIDTH="{{ entity.bbox[2] - entity.bbox[0] }}" HEIGHT="{{ entity.bbox[3] - entity.bbox[1] }}"{% endif %} {% if entity.tags %}{% for type in page.region_types %}{% if type in entity.tags.values() %}TAGREFS="REGION_TYPE_{{ loop.index }}"{% endif %}{% endfor %}{% endif %}>
                     <Shape>
                         <Polygon POINTS="{{ entity.boundary|sum(start=[])|join(' ') }}"/>
                     </Shape>
diff --git a/kraken/templates/pagexml b/kraken/templates/pagexml
index daea1ac00..596503065 100644
--- a/kraken/templates/pagexml
+++ b/kraken/templates/pagexml
@@ -39,7 +39,7 @@
         </TextRegion>
         {% endif %}
         <TextRegion id="{{ entity.id }}" custom="structure {type:{{ entity.region_type }};}">
-            <Coords points="{% for point in entity.boundary %}{{ point|join(',') }}{% if not loop.last %} {% endif %}{% endfor %}"/>
+            {% if entity.boundary %}<Coords points="{% for point in entity.boundary %}{{ point|join(',') }}{% if not loop.last %} {% endif %}{% endfor %}"/>{% endif %}
             {%- for line in entity.lines -%}
             {{ render_line(line) }}
             {%- endfor %}