I am in the middle of a major clean up of my software download archives, It would be useful to know what software and sample libraries can simply be downloaded and reinstalled from your account if disaster strikes. One of course may still want to keep a backup to save time/bandwidth. Things change pretty rapidly so please correct me if I am wrong.
 
To start here are a couple.
 
Yes
Cakewalk - via CCC
Toontrack- via new software manager.
Arturia - Via Software Centre.
EastWest composer cloud. (not sure about stand alone products)
 
No
IK-Multimedia - time restrictions on Sampletank 3 (new downloads at a cost)
 

ATM IK is the only one I can think of that I own and all my ST3 stuff is on my Raid-1 NAS. Thanks for reminding me that I also need to get it on my cloud storage.

EastWest also stand alone products (but not Platinum/Diamond except Choirs and HOP).
Sampletekk: reactivation upon simple request.
OrangeTreeSamples.
Native Instruments.
NomadFactory.
SonicCouture.
SlateDigital.
SoundToys.
Pianoteq.
Garritan.
eSoundz.
iZotope.
Waves.
PSP.
d16.
 

I'm impressed with that list ........how well it was structured.  

After a Windows 10 clean install and an unintended disk wipeout, I redownloaded Studio 1 V2 and PianoTeq with no problems.
 
I believe that the Pettenhouse and Sampletekk links expire after a certain time, though both are nice guys and might allow a redownload.
 
I'm not sure about NI. I looked at my page and it allows Kontakt, but not my full KU9 that I fortunately have on hard drive. It might depend on your original purchase as mine was a crossgrade on harddrive.
 
Oh I don't charge either. :P

Mesh
I'm impressed with that list ........how well it was structured.  

Beauty is in the eye of Lord Mesh.

bigcatt
I'm not sure about NI. I looked at my page and it allows Kontakt, but not my full KU9 that I fortunately have on hard drive. It might depend on your original purchase as mine was a crossgrade on harddrive.
 

I am not sure about Komplete either. I have a box of DVDs that it came on.  Its one of the vendors I need to investigate further.

Glyn Barnes

bigcatt
I'm not sure about NI. I looked at my page and it allows Kontakt, but not my full KU9 that I fortunately have on hard drive. It might depend on your original purchase as mine was a crossgrade on harddrive.
 

I am not sure about Komplete either. I have a box of DVDs that it came on.  Its one of the vendors I need to investigate further.

Yep, I think the larger libraries from Ultimate might be off limits. Then again, I don't see why they wouldn't allow us to re-download them if they are indeed taking the download-route.
Keep us posted, Glyn, if you get more news from NI.

No one mentioned XLN!

Sidroe
No one mentioned XLN!

Because Fleer couldn't decide on the order of it in his list.