Hi @R N ,
Thank you for your detailed response and time.
Using the following formula(text is my column name, please replace it with your column name.):
=OR(text="Product A",text="Product B",text="Product C")
Note: The comparison is not case sensitive.
SharePoint column validation supports a subset of Excel functions. While not all Excel functions are available, you can use common functions like AND, OR, IF, ISBLANK...
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