Originally Posted by Globaliser
IIRC, the airline that issues the bag tag is responsible for the costs of delivering the bag if it misconnects somewhere along the way, even if outside its control. In today's environment, you can understand why airlines might have become a little wary about assuming the risk of those costs when they don't have to.
No, it's the last carrier that is responsible for this - at least here in the UK.
I've never had problems getting bags checked through on separate tickets, but I had an airline refuse to check my bag through on a through booking with a through ticket where both sectors were operated by that same airline! Nearly missed my connection as a result, so wasn't very happy.