chromium/third_party/blink/web_tests/tables/mozilla/core/table_rules.html

<table border rules=none>
 <tr><td>rules</td><td>none</td></tr>
 <tr><td>rules</td><td>none</td></tr>
</table>

<br>

<table border rules=groups>
 <tbody>
  <tr><td>rules</td><td>row group 1</td></tr>
  <tr><td>rules</td><td>row group 1</td></tr>
 </tbody>
 <tbody>
  <tr><td>rules</td><td>row group 2</td></tr>
  <tr><td>rules</td><td>row group 2</td></tr>
 </tbody>
</table>

<br>

<table border rules=groups>
 <colgroup><col><col></colgroup>
 <colgroup><col><col></colgroup>
 <tr><td>rules</td><td>col group 1</td><td>rules</td><td>col group 2</td></tr>
 <tr><td>rules</td><td>col group 1</td><td>rules</td><td>col group 2</td></tr>
 </tbody>
</table>

<br>

<table border rules=rows>
<tr><td>rules</td><td>rows</td></tr>
<tr><td>rules</td><td>rows</td></tr>
</table>

<br>

<table border rules=cols>
<tr><td>rules</td><td>cols</td></tr>
<tr><td>rules</td><td>cols</td></tr>
</table>

<br>

<table border rules=all>
<tr><td>rules</td><td>all</td></tr>
<tr><td>rules</td><td>all</td></tr>
</table>

<br>