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Unity Terms-of-Service and use of SpatialOS



Hello SpatialOS developers,

As some of you might or might not yet have heard Unity has ruled that the use of their engine in combination with SpatialOS or other third-party cloud platforms constitutes a breach to their Terms-of-Service. This is as much news to you as it is for us at Improbable and we have not received any form of upfront warning.

We have always had a productive relationship with Unity, just like the ones we have with many other game engine providers. As of the posting of this message we have not had any form of formal communication or explanation as to the why of this change in their stance.

Improbable’s own Unity licenses have been revoked, which considerably hampers our ability to support you going forward. This unilateral decision also means that a live game using Unity on top of SpatialOS is now considered as a breach of their Terms-of-Service. Their decision is retroactive in nature so it applies to projects that are still in development.

We sincerely hope that Unity will quickly realise the repercussions and extent of their decision and reverse it. However we need you to help us raise awareness for all the negative consequences that their decision will have on you as game developers and on game development in general. You should reach out to your Unity account manager, Unity support channels and via social media to express your thoughts and concerns.

Read our full blogpost over here. Of course, we’re here on the forums or on Discord to answer any questions you might have.

Kind regards,

Duco - Head of Developer Community @ Improbable


Good evening again (depending on where in the world you are :wink: )!

The day has been long and intense. Not just from Improbable’s perspective but also the whole wider game developer community which has reacted to the clear lack of clarity in Unity’s Terms-of-Service.

Given that even for us the story is not about ourselves but rather about the many talented game developers that are using our platform for their project we wanted to share some thoughts on the general topic of the relationship between game developers and the platforms they use.

Please read it our blog post here and as always we are happy to hear your thoughts here, on our Discord or on our other social channels.



Duco, guys at Improbable… please do what you can to repair your relationship with Unity and talk them down. Yea, they have some buffoons at the helm, but now that the entire team over there knows what’s going on, i’m sure there is pressure on the business side to patch things up. There is no reason why you both can’t make bucket loads of $$ together. :slight_smile:

Being forced to migrate over to UE is going to be a huge issue for us (and i’m sure many other devs), and Unity without SpatialOS is just a total dead end.


Actually given the fact that they let you know a year in advance, and then again 6 months ago, it is making your company seem like you have taken a child-in-the-playground approach to doing business.

Trying to make a PR stunt of this was not the way to win them over, nor your developers.

As someone who was looking forward to using Spatial OS for our first big funded project, we can no longer trust improbable given the way they have dealt with this.

Our legal adviser has looked over both statements by both companies and ultimately yours comes off worse from a legal standpoint.

**dont even get me started on your own TOS, you have the nerve to point the finger but have you read your own? **


Dear all,

We have released a final statement to help bring more clarity to the various points that have been raised both by us and Unity over the past two days. As this statement explains we will, from this point on, only publicly address issues that users of our platform are facing.

Kind regards,

Duco - Head of Developer Community @ Improbable


Are you planning to contact games currently in production? I haven’t received anything about this.


Hello @cbdileo,

As our last statement indicates:

We have interpreted their exception for games to include our services’ physical operation on behalf of those customers (because otherwise it is meaningless) and intend to keep running unless we are prevented. Even then, we will not take down or ask anyone to take down anything unless proper formal legal channels are followed, not announcements or blog posts.

From that perspective you are currently not in any danger of a shutdown. We would still encourage you to reach out to Unity to confirm your case with them but there is no reason why you should not fall under their blanket statement about existing SpatialOS games still being in the clear. If there are any further developments that would impact you or any other of the developers using SpatialOS we will definitely reach out.



Hey everyone,

I’ve recently emailed Unity Support about this topic and my own (attempted) workarounds and this is what I’ve heard back from them. I’ve already forwarded things to Duco, so hopefully this helps them with other teams!

For a text transcript:

Berwyn Friday at 17:20

To whom it may concern:

I’m a solo developer that just subscribed to Unity Pro in the hopes of using Unity and SpatialOS together for a project. I have read the dueling blogposts, and honestly I’m in a bit of a pickle. I have not started my game project yet, and it’s not live, therefore I don’t qualify for the EULA by my understanding. Similarly, I was thinking that, perhaps, I could leverage Spatial workers that don’t use the Unity Runtime, but the Terms of Service definition of “Project Content” makes that murky.

Is it possible to get some clarification on

a) Whether or not I can use non-Unity workers on SpatialOS that my Unity game client (on an end-user machine) interacts with, or

b) If there’s another Unity-approved solution that provides the same service that SpatialOS does, or

c) Whether I can get a refund of my Unity Pro subscription so I can use that money towards another engine that enables SpatialOS.

I really love Unity and the technical direction it’s going and would absolutely love to continue using it, but my entire game concept relies on the managed workers and load-balancing that SpatialOS provides, and as a solo developer I don’t honestly have the time to iterate on operations and hosting when I could be iterating on my game instead.

I appreciate any consideration you’d give this!

Andrew Yesterday at 15:54

Hi Berwyn

Thanks for getting in touch and for considering Unity as an option for your project development.

Sorry to hear that you were affected by our relationship with Improbable.

  1. Could you please elaborate a bit more on this one?

  2. If your project needs to run a Unity-based game server, you can use your own servers or generic cloud instances (like GCP, AWS or Azure), they are covered by our EULA.

  3. sorry, this is still not considered, We are still working on this for all of our users while we resolve our dispute and we will post a notification in our blog as soon as possible

Best Regards,

Customer services Engineer

Berwyn Yesterday at 16:02

Hi Andrew,

In regards to #1, what I mean is could I (within the bounds of the ToS) construct a C# server worker (or a C++ or Java one for that matter) that does not use Unity code or the Unity Platform in any way and deploy it to SpatialOS? My reading of the ToS confuses me in this regard, since the term “Project Content” makes things murky.


Andrew Today at 12:50

Hi Berwyn

Thanks for the clarification.

Our legal team is still working on this, for the moment it is not considered.

Best Regards,

Customer services Engineer

For posterity:
Unity3D transcript.pdf (70.8 KB)


Dear SpatialOS devs,

We are happy to confirm that Improbable will continue to actively support game developers on Unity Engine, and develop our SpatialOS Game Development Kit for Unity.

We are also highlighting a new feature on our roadmap, with support for mobile development due to be released in pre-alpha for experimentation shortly. Read our blog post here.

Kind regards,
Duco van Amstel - Head of Developer Community


This is great to hear.

Full steam ahead. :slight_smile: