1) Create a feature. On the FeatureActivated(), registed the event receiver(a single class file) against mutliple lists
Add an event receiver to a specific list programmatically
for example:
public override void FeatureActivated(SPFeatureReceiverProperties properties)
{
SPWeb oWeb = (SPWeb)properties.Feature.Parent;
oWeb.Lists[list1].EventReceivers.Add(_eventType, Assembly.GetExecutingAssembly().FullName, "EventReceiverProject1.EventReceiver1.EventReceiver1");
oWeb.Lists[list2].EventReceivers.Add(_eventType, Assembly.GetExecutingAssembly().FullName, "EventReceiverProject1.EventReceiver1.EventReceiver1");
// add for 10 lists
}
2) You can have one content type that is used in all the 10 lists and and then attach the event receiver to this content type
How to Add an Event Receiver to a Content Type by Programmatically in SharePoint