Hello everybody,
I am new to the community. Therefore, please excuse me if I should forget any details 
Topic: In our corporation we have a special use case, regarding Jira Software projects.
I would appreciate your feedback 
First of all, let me give you some basic information about the system/applications:
* We run Jira Server
* Version: 7.11.1 (planing on an update next week probably)
* Java version: 1.8.0_102
* Jira Core/Software 7.11.1
* Jira Service Desk 3.14.1
* The server runs on Ubuntu 18.04.1 LTS
* The installation of Service Desk is somewhere else...
* I am global admin in Jira
* I have access to the installation (Core/Software) on Ubuntu
* I do not have access to the installation (Service Desk) on <OS>
Problem: Our corporation works with partners.
These partners should have access to our Jira Software projects (we already have this). However, there will be certain future developments, to which only certain partners should have access to.
The whole thing gets even more complicated, because now we will start introducing epics, stories, etc.
Is it possible to control, which epics, stories, tasks etc. can be viewed by which partner?
Obviously, the corporation does not want to use any addons from the marketplace.
Thank you all in advance 
PS.: In case you do not understand or misunderstand something because of my language skills, you should know, that english is not my native language. Please do not hesitate to depict something if anything is wrong 