If this thread is still about OW airlines checked bags policy ?
To be clear Cathay Pacific currently will check bags through to other OW airlines on separate PNRs

Yes, as noted in the wiki for this thread.

Hi,

Curious to know how airlines charge each other behind the scenes...

Let's say pax is flying HKG CX LHR BA EDI, on one ticket.
1) Bags didn't make it onto the CX flight so does not turn up in EDI, BA pays for pax's shopping bills and sends those + the cost of couriering the bags to pax address all to CX?
2) Bags arrived to LHR but somehow got lost by LHR, BA sends half the bill to CX?
3) Bags made it to BA handling in LHR but somehow wasn't load onto EDI flight. BA pays all?

Then let's say pax is flying LHR EDI on a separate ticket, but CX checks the bag through to EDI as per CX more generous policy.
1) Same scenario as above, CX pays all?
2) CX pays all instead of half half
3) CX still pays all?

Another scenario....
Let's say pax is flying HKG CX MAD IB LIS
1) If one ticket...Passport control at MAD was held up and pax missed their connection. IB's baggage handler had to retrieve pax's bag from original flight and then store and reload it onto the next flight that IB booked pax onto. Let's say IB's handler charges per-action. Does CX and IB pay half half?
2) On separate tickets but CX checked bags through, CX pays for all of IB's extra handling costs?

Was the policy change driven by cost saving as supposed to revenue protection? If BA offered a check through service at a cost-neutral or even profit making price would there be a market?

Thank you for reading....

I don't know all the details, but based on a previous conversation I had with baggage counter, it is my understanding that while the last carrier is responsible for reimbursing the affected pax, all airlines printed on the bag tag (in this case, CX and BA or CX and IB) share the cost. It doesn't really matter whose fault it was or who decides to check through. After all, it is quite difficult to track. The airlines split the bill using an IATA-set equation (thus nothing oneworld-specific) that takes into account of both the number of flights each carrier has on the tag and the distance of the flight, I believe.

Fewer airlines through-check bags these days partly to save bag reimburse cost but also partly because free baggage allowance is not as simple as it used to be. In the past, if the itinerary touched the Americas, it was 2pc. Otherwise, it was 20kg for Y, 30kg for J, or 40kg for F. Now, if the airline checking you in cannot read the bag allowance and extra bag fee of the downstream ticket, they will have a hard time knowing how much you can bring and/or how much needs to be charged. Oneworld airlines should all be able to access each other's ticket, but it is another story to know how much to charge if you are checking more bags than your allowance.

On a related note, CX has quietly changed its policy to through-check to separate ticket only for oneworld carriers. https://www.cathaypacific.com/cx/en_...g-flights.html Previously, CX would do that to all interline partners. Maybe CX has a hard time reading the baggage allowance of downstream tickets if not oneworld.