I'm looking at a non-stop LAX-DCA on Alaska metal.
RT fare is $338 on Alaska and I know I would get 100% EQM on CO.
I can get the same itinerary for $50 less by booking it on Travelocity with the outbound having a DL flight number but on AS metal. The DL is U or T fare which I know only gives 50% EQM on CO.
Am I correct that I would still get 100% EQM by doing this because it's the metal I fly that counts?
Thanks for your help.

It's the ticketing carrier and fare class that counts, not whose airplane you are traveling on - the exception being CO/COEX flights booked on co.com. If you ticketed on co.com with a CO ticket, and flew CO metal, 100%EQM is assured. Likewise, if you booked anywhere else for an AS ticket in any fare class, you would earn 100%EQM. Almost all published AS fare classes earn 100%EQM.

Any DL ticket booked in their L,U,T class regardless of the booking mechanism is 50%EQM, likewise any NW ticket in their V,L,T,K class is 50%EQM regardless of the booking mechanism - and in both cases, regardless of who is operating the flight. Any CO ticket in the deep discount bucket operated by NW or DL is also 50%EQM.

In short - either ticket your itinerary on AS stock with an AS fare code, or you will earn 50%EQM in the example you cited in the post.

Thanks for the quick reply.

Isn't it interesting that CO gives 100% EQM for AS - a non-Skyteam Partner that basically partners with anyone yet they only give 50% EQM for flying on DL - a Skyteam Alliance Partner.

I think CO doesn't understand what team they are supposed to be signed on with.....