I've been spending days trying to solve the memory leak in a small menu bar application I've wrote (SC Menu). I've used Instruments which shows the leaks and memory graph which shows unreleased allocations. This occurs when someone views a certificate on the smartcard. Basically it opens a new window and displays the certificate, the same way Keychain Access displays a certificate. Whenever I create an SFCertificateView instance and set setDetailsDisclosed(true) - a memory leak happens. Instruments highlights that line. import Cocoa import SecurityInterface class ViewCertsViewController: NSViewController { var selectedCert: SecIdentity? = nil override func viewDidLoad() { super.viewDidLoad() self.view = NSView(frame: NSRect(x: 0, y: 0, width: 500, height: 500)) self.view.wantsLayer = true var secRef: SecCertificate? = nil guard let selectedCert else { return } let certRefErr = SecIdentityCopyCertificate(selectedCert, &secRef) if certRefErr != errSecSuccess { os_log("Error getting certificate from identity: %{public}@", log: OSLog.default, type: .error, String(describing: certRefErr)) return } let scrollView = NSScrollView() scrollView.translatesAutoresizingMaskIntoConstraints = false scrollView.borderType = .lineBorder scrollView.hasHorizontalScroller = true scrollView.hasVerticalScroller = true let certView = SFCertificateView() guard let secRef = secRef else { return } certView.setCertificate(secRef) certView.setDetailsDisclosed(true) certView.setDisplayTrust(true) certView.setEditableTrust(true) certView.setDisplayDetails(true) certView.setPolicies(SecPolicyCreateBasicX509()) certView.translatesAutoresizingMaskIntoConstraints = false scrollView.documentView = certView view.addSubview(scrollView) // Layout constraints NSLayoutConstraint.activate([ scrollView.leadingAnchor.constraint(equalTo: view.leadingAnchor), scrollView.trailingAnchor.constraint(equalTo: view.trailingAnchor), scrollView.topAnchor.constraint(equalTo: view.topAnchor), scrollView.bottomAnchor.constraint(equalTo: view.bottomAnchor), // Provide certificate view a width and height constraint certView.widthAnchor.constraint(equalTo: scrollView.widthAnchor), certView.heightAnchor.constraint(greaterThanOrEqualToConstant: 500) ]) } } https://github.com/boberito/sc_menu/blob/dev_2.0/smartcard_menu/ViewCertsViewController.swift Fairly simple.