Originally Posted by eponymous_coward

Codeshares have additional flight numbers. E.g. AS 1/LY 6001 (this is 100% made up as an example). Same flight, different numbering. AS 1 shows up as an LY flight and could be shown as such on an LY ticket (probably with a “flown by Alaska Airlines” disclaimer).

Interlining implies both airlines can have flights on the ticket so your “interline the other way” question doesn’t make sense. If you’re asking “can I go to Alaskaair.com and buy a SEA-TLV ticket that has LY flights” the answer is no. But if you went to Expedia and got a TLV-SFO-SEA-ANC-OTZ ticket issued, AS is probably flying some of those segments (at least ANC-OTZ). Does that explain this?

PS: AS partner award tickets are interlined, not code shared, unless QX or OO is flying the plane with the Inuk gentleman on the tail.