Then there is a small advantage to use AVs from different vendors: files will be scanned by different AVs.
By default, your AV will scan all files that are read and written. So when a workstation accesses a file on a share, this file will be scanned by the AV on the server and by the AV on the workstation.
In a situation were AVs are identical on the server and workstation, having the file scanned twice doesn't bring you extra security.
But if the AV on the server and on the workstations are different products (different vendors), then there is an small increased probability of detection because one AV might detect something that the other doesn't.
Of course, this is the case for true positives as well as false positives.
You'll have to decide if this small advantage warrants the overhead of dealing with 2 AV vendors.
SANS ISC Handler
Microsoft MVP 2011-2016 Consumer Security, Windows Insider MVP 2016-2018
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