Hi Katy,

Unfortunately, our conditional formatting for our fields will only work off of two things:

- Filtering Expressions (https://www.labkey.org/Documentation/wiki-page.view?name=filteringExpressions)
- Regular Expression (RegEx)

More details on conditional formatting can be found here: https://www.labkey.org/Documentation/wiki-page.view?name=fieldEditor#conditional

Neither of these conditional formatting options would be able to identify duplicate values in a column. To have the data be identified as a duplicate, you would need to have this identified programmatically in some way, like using a SQL query to look for this data and flag it somehow or having something like Javascript or some scripting language to read the data and identify the duplicates and flag them that way.

Regards,

Jon