I have the following suppression formula:

 

{?@Group} <> 'Adrian Steel'

 

I need to be able to add multiple employer names to the formula.  When I try to add more than one, I receive a message stating "A boolean is required here".  The following is the formula that produces the error:

 

not {?@Group} in  ['Adrian Steel','Allegro Development']

 

Does anyone have any ideas?

 

Thank you in advance.