Originally you said "Only if you distribute the code."
If you run software on your server, and someone outside accesses the software via a web page, even if the software is still only running on your server and hasn't been distributed outside the company, if it's under the AGPL, the company must make available the source code.
If i run a AGPl database like mongo(before they switched to their own license) and had a web app that used it to persist and read data. I would not be required any modifications to mongodb because i didn't trigger copyright. Now if I let people connect to mongodb through some managed service that i was selling, i would trigger copyright because mongo protocol is proprietary and covered by copyright law. This is a textbook example how it works.
If you used a brand new implementation of whatever protocol Mongo uses that's under a less restrictive license than AGPL, you would not trigger any obligation to share the source code.
"Proprietary" in "Proprietary protocol" pretty much means "specific" / "non-standard". And you can't legally prevent someone to reimplement your proprietary protocol. I don't even think you can copyright the protocol itself. You can copyright the documentation / specification document at best, and actual implementations of it.
In "proprietary software", though, "proprietary" means "non-tree", that is, not open-source as defined by the OSD / not free software as defined by the FSF / the GNU project. The meaning of this word is very different in those two separate concepts.
The AGPL network clauses only trigger on modification, so if you deploy mongo without modification and don't distribute any code, thats fine, even if you expose mongo on the public internet.
Read the AGPL again. It has specific clauses that say that integration, not modification, of AGPL’d software applies it. Just using the AGPL’d software is the trigger.
I don't see anything about integration in the license, there is no trigger about use AFAICT.
However, in item 13, it specifically says "if you modify the Program":
13. Remote Network Interaction; Use with the GNU General Public License.
Notwithstanding any other provision of this License, if you modify the Program, your modified version must prominently offer all users interacting with it remotely through a computer network (if your version supports such interaction) an opportunity to receive the Corresponding Source of your version by providing access to the Corresponding Source from a network server at no charge, through some standard or customary means of facilitating copying of software. This Corresponding Source shall include the Corresponding Source for any work covered by version 3 of the GNU General Public License that is incorporated pursuant to the following paragraph.
c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.
See also, paragraph (b):
b) The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to "keep intact all notices".
Originally you said "Only if you distribute the code."
If you run software on your server, and someone outside accesses the software via a web page, even if the software is still only running on your server and hasn't been distributed outside the company, if it's under the AGPL, the company must make available the source code.