TeamViewer

TeamViewer has previously sold a "perpetual" license for versions 8-12, but after switching to a subscription-based Software As A Service model, they have pestered "perpetual" license owners to "upgrade" to a subscription license for their newer versions.

Recently, they have announced support will be fully shut down for these versions: https://community.teamviewer.com/English/discussion/141015/end-of-support-for-teamviewer-versions-11-and-12/