Identify Duplicates based on multiple conditions/columns

Hi, v_mark 

Based on your description, I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

You may create a custom column with the following m codes.

let 
device=[Device],
status=[Status],
state=[State],
sn=[SN],
tab = Table.SelectRows(#"Renamed Columns",each 
[Device]=device and 
[Status]=status and 
[State]=state and (
Text.EndsWith([SN],sn) or Text.EndsWith(sn,[SN])) ),
re = Table.RowCount(tab)
in 
if re>=2 
then 
"duplicate"
else null

Result:

Best Regards

Allan

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