I'm adding CloudKit sharing to an app that already uses NSPersistentCloudKitContainer successfully. Private-database sync works flawlessly across my devices. But every attempt to create a share hangs: container.share(_:to:) never returns and never invokes its completion handler. No error is thrown, nothing prints, the operation simply stalls indefinitely. Environment: Xcode 26, iOS 26.5, iPhone 16 Paid Individual developer account Single NSPersistentCloudKitContainer, two stores (private + shared) What works: Private database sync across multiple devices (iPhone + iPad) is reliable eventChangedNotification reports setup/import/export events succeeding continuously CloudKit schema was initialized via initializeCloudKitSchema() and record types appear in the CloudKit Console The problem: Calling share on a root object hangs. I've reproduced the identical hang with all three API variants: async/await: try await container.share([object], to: nil) — never returns Completion handler: container.share([object], to: nil) { ... } — closure never fires UICloudSharingController preparation-closure initializer — the closure never fires, controller presents an empty sheet A log line immediately before the share call prints; a log line inside the completion/closure never does. My two-store setup (per WWDC21 session 10015): swiftlet sharedURL = privateDesc.url! .deletingLastPathComponent() .appendingPathComponent("YerBoat-Shared.sqlite") let sharedDesc = NSPersistentStoreDescription(url: sharedURL) let sharedOptions = NSPersistentCloudKitContainerOptions(containerIdentifier: "iCloud.com.example.app") sharedOptions.databaseScope = .shared sharedDesc.cloudKitContainerOptions = sharedOptions sharedDesc.setOption(true as NSNumber, forKey: NSPersistentHistoryTrackingKey) sharedDesc.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey) container.persistentStoreDescriptions = [privateDesc, sharedDesc] Possibly relevant: the objects I'm trying to share (and their related records via cascade relationships) were all created before I added the sharing/shared-store code. Could existing records in the default zone fail to migrate into a shareable zone, causing the hang? Questions: What causes share() to hang silently with no error and no completion? Does sharing require records to be created after the shared store exists, or should existing private-database records be shareable? Is there a required step between initializeCloudKitSchema() and the first share() call that I'm missing? I've reviewed WWDC21-10015 and TN3164. Any guidance appreciated.