Possible Clues:

• ASCAP and A.S.P.C.A.: Abbr
• A.C.L.U. and others
• Assns., for instance
• Clubs or leagues: Abbr
• Common interest gps
• AAA et al
• CARE and PETA, e.g
• Trade grps
• Nonprofits, e.g.: Abbr
• List for charitable givers, for short