You can also provide downgrade rights to a software license so that the same license can be used for licensing: prior versions of the software being added (or) other software(s) belonging to the same suite.
Follow the steps mentioned below to provide downgrade rights to a software license.
Note: Steps have been written assuming you've filled the software license form [see: creating software license to understand how a license form is filled] and are about to provide the license with downgrade rights.
Under Downgrade Rights section:
Select Sotware [prior version of the software being added (or) other software(s) belonging to the same manufacturer] from dropdown
Provide License Key and click Add button
Save the license

Note:
Multiple software(s) (belonging to the same manufacturer) too can be bound by a single software license with downgrade rights
Downgrade rights can be provided to software licenses not only when they are being added but also while editing them [see editing software license for more details]
You can also add Upgrade licence for existing software.
Follow the steps mentioned below to upgrade a software license.
Click Add New dropdown --> and select Upgrade License option

Add License page opens up
Select Software License which is to be updated using Upgrade From dropdown
Select Software License using which the exisiting Software License will be updated from the Upgrade To dropdown
Upload the existing purchased license using upload purchased license icon.
Specify License Key and provide Vendor Name
Specify the license purchase cost
Provide description specifying reason behind license upgrade
Click Save
Note:
Software license being upgraded will be converted into a downgrade license