Based upon what I read at Alaska's website noted above, I'd be led to believe that AS would honor all of AA's fare codes as well. Nowhere does it specify no credit for this or that booking class.

By contrast, the American Airlines website, under AAdvantage --> Partners & Mileage Programs --> Airlines clearly states which fares purchased on Alaska will earn you mileage and which will not. Check it out right HERE

While recently booking a Seattle to Ft. Myers roundtrip on aa.com, I plugged in my dates and was quoted a very reasonable fare of about $228.00 inclusive. Scrolling down, there were much higher fares also available. What reasonable person would pay the higher non-O class fare if AA offered about a dozen different options to get to RSW at the $228.00 fare?

More to the point, at no time during the reservation process did I see any highlighted (or non-highlighted or even small print) warnings that clearly stated that the flights booked might not receive mileage credit on a partner airline.

As it is currently presented per Alaska's website and AA.com's reservation process, any reasonable person would think they could earn miles on that O Class reservation to Ft. Myers.

I feel that Alaska needs to work more closely with its Mileage Plan partner airlines towards providing a clear outline including a warning in the reservation process of which fares will earn mileage and which will not. Until such time as they do that, they really should credit any and all tickets purchased prior to their announcing mileage earning fare categories on partner airlines.