Originally Posted by Donna49

By being a member of IATA, they have to interline with other IATA carriers as a condition of membership. No individual airline agreements, although nothing precludes an airline from doing so. Just being an IATA member airline is a defacto agreement with all IATA airlines.

To answer the OP's question as to who AS has interline baggage agreements with, only Alaska knows. But by being a member of IATA, Alaska MUST interline with other IATA carriers, whether Alaska has an agreement with a specific IATA carrier or not.

I just called AS res to verify the above.