Recently, I had had an issue which required making a folder shareable on my local LAN. I noticed that under Ubuntu 16.04 there was no "share" tab in Nemo for making a folder shareable on the local LAN.
I also took a look at my other computer which is running Ubuntu 14.04. In that computer folders accessed with Nemo have a "share" tab. So it seems that the upgrade to Ubuntu 16.04 "removed" the share "tab" for Nemo.
I am using Nemo as the file manager rather than Nautilus under Ubuntu 16.04. Nautilus is still available with the "share" tab. However, utilizing Nemo as the principle file manager seems to have created an occasional situation where my computer under Ubuntu 16.04 is sometimes not recognized by the local LAN. Is there a way to add the "share" tab (enable sharing) in Nemo under Ubuntu 16.04 which should resolve the occasional concern of the computer not showing-up on the local LAN. (Evidently Nemo "covers" Nautilus, herby "hiding" the folder's share property.)