A method and arrangement for temporarily withholding notifications with client data of at least one observed client to a watching client when the watching client has an ongoing subscription for receiving the notifications from a client data server. When the watching client receives a subscription suspend trigger, the watching client sends a subscription suspend message to the client data server indicating that client data notifications should be temporarily withheld while retaining the subscription. When the watching client subsequently receives a subscription resume trigger, the watching client sends a subscription resume message to the client data server indicating that the suspended subscription shall be resumed and allowing client data notifications to be delivered again. The watching client then subsequently receives client data notifications according to the subscription.