My 2 cents 🙂

declare @table table(

string varchar(50)

)

insert @table (string)

select '[gdhdnuidd] 1st Party SW'

union all select '[abcdef] Client'

union all select 'testbusiness'

select

case

when charindex(']',string) > 0 then right (string, (len(string)- charindex(']',string)))

else string

end finalstring

from @table