Channel ownership in a publish-subscribe system

To manage channel ownership in a publish-subscribe data processing environment, a determination is made at a first server that a subscription request from a client relates to a channel, the channel having a channel identifier. At an exchange component in a messaging middleware, a session queue associated with the client is bound to the channel. A mandatory delivery message is configured to be routed using a publisher identifier by the exchange component, the publisher identifier being related to the channel identifier. The mandatory delivery message is communicated from the first server to the exchange component to indicate an intent of the first server to become a publisher of the channel. The mandatory delivery message causes the channel ownership of the channel to be limited to a single publisher.