Hi, 

Can you use special characters in a keyword in eDiscovery? Something like "2-1234"

I think this article helps - https://msdn.microsoft.com/library/ee558911(v=office.15).aspx

A word (includes one or more characters without spaces or punctuation)

A phrase (includes two or more words together, separated by spaces; however, the words must be enclosed in double quotation marks)

Hi Lindsey.7521,

What scenario is it in your question? On SharePoint or any other platform?

Regards,

Melon Chen
TechNet Community Su