Multiple Multisite networks on the same domain?

You can not run different networks or different Multisite installations under one domain in the default possibilities of WP. But you can use one Multiste with multiple networks with the help of a plugin – https://wordpress.org/plugins/wp-multi-network/

With this plugin get you the chance to create different networks with sites in one installation, one Multisite. Like the follow structure example.

http://www.companysite.com/education
     -- /www.companysite.com/education/de
     -- /www.companysite.com/education/en
     -- ...
http://www.companysite.com/marketing
     -- /www.companysite.com/marketing/de
     -- /www.companysite.com/marketing/en
     -- ...
http://www.companysite.com/innovation
     -- /www.companysite.com/innovation/de
     -- /www.companysite.com/innovation/en
     -- ...