They require you to acknowledge some terms that grant you access to the Unreal Engine source code. They grant it by adding you to their GitHub org which has the engine source code as a private repo.
Is it? How else do you selectively grant access to a repo? Orgs are the normal way, it's just not normal to have a project which is proprietary and somewhat private but available to 400k people.
Github just needs to rethink how tagging all users works and a way to prevent this.
I accepted those terms, and was added to Unreal's repo, but didn't get a notification. I think the mentioned group is some subset of the repo users, but 400k is such a big number that I'm not sure who they could be.
Unreal engine is open source but in a private GitHub repo. Anyone can link their GitHub account with their epic games account which adds them to the team.
That's a misleading, obfuscating way to make the difference. I guess the OP means an OSI-approved licence.
If you write your own licence (not recommended, but some developers and especially corporations do) it could be even fully compliant, but not approved.
"open source" and "free software" are two words for the exact same thing.
Both of them are pretty poor descriptors. "open source" doesn't convey the legal freedom you are granted (as you have just found out), and "free software" makes it sound like it's just about price.
If someone lets you see source code but doesn't allow you to do anything with that code it's not what people would call "open source", you could probably call it source-available or something. "open source" has a specific legal definition that means code released with a permissive license.
If you read the page you linked more carefully, you will see that OSI does not own a valid trademark for "Open Source", only for "Open Source Initiative".
OSI in fact tried to file for a trademark on 'Open Source' in 1999 [1], but failed because the term is 'too descriptive'.
You can download it via Epic Game Store without joining the org. Github organization is for contribution from non-employees as well as source code for various projects (like engine demos).
Only for those still using Windows. The head of Epic has some bizarre complex against Linux, so they refuse to release binaries (or the Epic Game Store at all) for Linux. So the only way to install Unreal Engine is to link your Github account to their org, clone it, then build it from source. Which takes a few hours and something like 70gb of disk space while building.
Huh. And yet why is that sort of annoying forced registration not considered 'antisocial', but this accidental tagging is resulting in calls for the poster to be banned?
They sell it (access to the source for the engine) under a commercial license. They were going to have _some_ sort of registration system, so that they can make sure everyone who downloads it paid for it. They reused GitHub for both distribution and registration.
Access to the UE4 source code is free. They probably sell licenses that let you do more than the free license, but the Github thing is not used to gate purchases. I don't know why they do it like this to be honest, they could just put the free license in the repo, that's pretty common practice.
Because it's not a free license. Once you get a million dollars or so in revenue, they take a substantial cut.
The idea is that nobody is going to get a million dollars in revenue from a game without being visible enough that Epic's receivables department can bill you. So they can ignore the 99.99% who download it and never get a hit.
I'm amazed that 400,000 people have downloaded Unreal Engine, though. It's really complicated, hard to use, takes hours to compile, and is only worth the trouble if you're making an elaborate 3D game. Not that many people do that.
This is just arguing semantics. You don't have to pay anything for the initial download, so there is no legal reason for this. They could just public the repo and put their license (including the $1MM+ royalties) in a LICENSE file.
I suspect the "real" reason for the current rigamarole is to get your details for their marketing team.
Oh, interesting. I thought you could download binaries for free and source access cost extra. I’ve never used it, so I suppose whatever story I read about it was less clear than I thought.