If you want to upload mods to the Fallout 4 depository on Bethesda.net, you're going to have to own the game for starters, in a new list of anti-mod-piracy tweaks that Bethesda is making to its Fallout experience. It's also going to require you to link both Bethesda accounts and Fallout 4 accounts to make sure you are who you say you are and that if you try and share a mod that's not yours, you will be caught out for it.
Mod piracy is a relatively recent phenomenon in a larger-scale sense, but it's been ongoing for a long time now, with people downloading mods and uploading them somewhere else under their own name - essentially taking credit for others' work. Without paid mods being common place, this doesn't cause much financial hardship, but it can lead to mod makers receiving flak for features that don't work, after the mod being released on a platform it wasn't intended for.
Bethesda will now have a much better idea of who is taking part in mod piracy and can move to ban those accounts if it takes place. At the very least, this forces mod pirates to buy a new copy of the game each time they do it. While that isn't the biggest disincentive in the world, it should be enough to stop the casual pirates causing problems for legitimate modders.
What are some of your favourite mods on Fallout 4?