NOAH KANTROWITZ

React and Patents 2017-09-25

Over the past several weeks there has been an evolving discussion about the licensing of React, a popular library for building complex user interfaces. There has been a lot of conflicting information posted about the state of React, what kind of licensing terms are involved, and why all of this matters. I would like to try and set the record straight to the best of my ability. But first:

A Disclaimer

I am not a lawyer and nothing in this post should be considered legal advice. If you have any specific questions about any of this, please talk to a licensed intellectual property attorney in your local jurisdiction. This is for entertainment purposes only. This is just my opinions/knowledge, not those of my employer, Facebook, the Apache Software Foundation, or anyone else.

Okay, with the disclaimer out of the way, let’s rewind, where did all this start?

The Story Up Until Now

While we could start way back with the initial creation of React, that was a long time ago and the part of the story we all care about begins in April 2017. In a somewhat unassuming Jira ticket, one of the Cassandra team asked the Apache Software Foundation legal affairs team if directly integrating with RocksDB was acceptable. I hear you say “RocksDB? I thought this was about React!” well that was brought up soon after in the same ticket, as both RocksDB and React were made available under the same license. This was resolved a few months later in July when the ASF legal team made the call that the license terms used for RocksDB (and therefore React) were incompatible with the requirements on ASF projects. This was quickly picked up by the media and run with headlines like “Apache says ‘no’ to Facebook code libraries”.

We’ll come back to RocksDB later, but with React this kicked off a firestorm of concerned and confused users asking what was going on. There was some discussion for a few weeks as to if React should be changed to a different license, but in mid-August this was closed with Facebook confirming that they felt the current license was appropriate.

Then, unexpectedly, a few days ago (September 22nd) Facebook announced they would be relicensing React and several related projects to use the MIT license.

Okay, so that’s the whole history, let’s look at some major questions that came out of these few months:

Who Owns React (and RocksDB)?

To get it out of the way, code is in general owned by whomever writes it. If you write code as a part of your job, it is owned by your employer, give or take what is in your employment contract. Facebook does require a contributor license agreement (CLA) for their projects, and the CLA grants Facebook some strongly worded rights for copyright use and patent access, but in the end each contributor remains the owner of the copyright in their contribution. This means that while React is managed by Facebook, and they do own a lot of the copyright over their projects, in the end they are actually owned by the collective community of developers that works on them. In the case of RocksDB specifically there is also a large chunk of the code which is owned by Google, as it is an outgrowth of an earlier Google project called LevelDB.

Ownership is generally thought of in terms of copyright ownership, as that’s the more directly relevant bit, but another factor in the control of software is who owns any patents which cover the software. We’ll leave this part for later in this post as it’s a much more complex topic.

What Was The Original License For React (and RocksDB)?

The license used originally by Facebook has two main parts, a copyright license and a patent license. The copyright license half is pretty straightforward, a 3-Clause BSD license. This is part of a family of minimalist copyright licenses that allow use, copying, and modification of the code. Without this license, those rights would remain exclusively with the copyright holders (i.e. the person or company which wrote each section of the code). The BSD license (usually in 2 or 3-clause variants, sometimes 4) is fairly well known and the requirements you must meet to use those licensed rights (preserve the copyright notice and license, don’t use Facebook’s name in endorsements, don’t sue anyone because the code doesn’t work) are quite reasonable.

The second half is a patent license, which says that anyone using the software is allowed to use any Facebook patents that might cover that software so Facebook cannot sue them for patent infringement. The goal here is the same as with the copyright license, making sure users have enough rights to be successful open-source citizens while protecting Facebook and the other rightsholders involved.

Facebook has termed this a “BSD+Patents” license, though this should not be confused with the OSI-approved license also called “BSD+Patent” (or sometimes BSD-2-Clause-Patent) as the two are unrelated.

What Problem Did The ASF Have With BSD+Patents?

As mentioned in the previous section, the use of the BSD license for copyrights was 100% okay with everyone, the issues all revolved around the patent license. This was something created by Facebook specifically, so to start with it was not a well-known quantity in the same way as things like the BSD or MIT license would be. While using standardized licenses (or more specifically, licenses recognized by the Open Source Initiative) does certainly make life easier for open-source lawyers, it isn’t a specific requirement.

The Apache Software Foundation does its best to make the projects under its umbrella be somewhat uniform from a legal perspective. If you get a legal “okay” to use one of them, you can almost certainly use any other ASF project. This is important for ecosystem stability as many ASF projects depend on other ASF projects to function. We’ll get to the Apache-2.0 license in more detail later, but the ASF created it to help in this mission, to provide a unified set of licensing terms for all ASF projects. But the open-source ecosystem is a big place, and many ASF projects want to depend on libraries not from the ASF and thus sometimes under different license terms. So the doctrine used by the ASF legal team is that other licenses are okay as long as they do not put any more requirements on the end user than the Apache-2.0 license does. So for example, pretty much all software in the world depends on zlib, which is distributed under the zlib license, but from the point of view of the ASF crew, that is less restrictive than Apache-2.0 so it doesn’t make life any harder for end users.

The problematic section of the patent license was under what conditions the license would be revoked. While most copyright licenses are given as irrevocable, it is normal for patent licenses to include a termination clause in the case of a lawsuit over the software. This helps to protect the company, if they get sued they can at least prevent you from continuing to benefit from their IP for the duration of the lawsuit. But that said, the Facebook patent license went a lot further: “The license granted hereunder will terminate, automatically and without notice, if you … initiate … any Patent Assertion against Facebook or any of its subsidiaries or corporate affiliates”. So rather than being scoped to just lawsuits over the specific project, any patent suit brought against Facebook would terminate the patent license. The ASF Legal team decided this represented a restriction above and beyond the Apache-2.0 license, and so it could not be used with ASF projects.

It should be repeated that this was a decision by the ASF Legal team for ASF-controlled projects, that’s it. This was not an abstract judgment that Apache-2.0 code can’t be used with BSD+Patents in general, nor was it any comment on the quality of Facebook’s code or on their patent license as being good or bad. It was specifically to ensure the licensing goals of the ASF remained safe, nothing more.

So What Happened To RocksDB?

In response to the original decision from ASF Legal, the RocksDB team quickly switched from BSD+Patents to Apache-2.0. There isn’t a lot of public information on how this change went down or why, but given it happened within a few hours I’m guessing it was considered fairly uncontroversial by everyone involved. As mentioned earlier, there is a lot of code from LevelDB still in use, which is owned by Google and will continue to be made available under the terms of the 3-Clause BSD license.

One slight addendum, since this will come up again with React: I’m not actually 100% what the legal basis for the change of license was. Normally you need approval from all copyright holders before changing a license, but it is possible the Facebook legal team decided the sublicensing requirement of the Facebook CLA made it okay to relicense in this fashion without getting approval. Or it’s possible they just figured everyone would be okay with it, which is probably correct.

Why Did Facebook Want The Broad Termination Clause?

Without getting too far in to the details, one major problem facing the software industry right now is a plethora of patent lawsuits from companies that buy out very broad or wide-reaching patents and then use them to try and extract settlements from a large number of software companies by threating litigation. These are colloquially called “patent trolls”. Regardless of your personal feelings on the issue, Facebook considers this a threat to their business and was using the broad termination clause across all of their open-source software to try and take some wind out of the sails of future trolls as if the troll was using anything under the Facebook patent license, if they filed a lawsuit over one of the troll patents, Facebook could counter-sue using one of theirs.

This defensive measure was deemed important enough to reject the initial request for relicensing React. And speaking personally, I totally understand that impulse. I agree that troll lawsuits are a chilling scourge on our industry and in general I support legal defense machinery to try and reduce them.

Why Did Other People Not Want The Broad Termination Clause?

While you might initially think “but I would never sue Facebook”, things are often more complex than that. For other large companies, this one-sided termination clause effectively means the company as a whole is giving up the right to pursue legitimate patent infringement cases against Facebook. Given the scope and scale of many patent portfolios, this represents an unacceptable risk to many (already risk-averse) legal departments.

For smaller companies, especially VC-backed startups, suing Facebook would likely have never been an option in the first place even if Facebook was very clearly infringing as the legal costs can be immense. However the other shoe dropping is that many startups want to end up getting acquired by larger companies, so all the same issues get pulled back in. While I don’t know of any examples citing React specifically, acquisition deals fall apart all the time over intellectual property concerns so this is something even startups should take seriously.

That said, for some cases it really is okay. I personally used React for some projects, like the dashboard that powers my home information system, when it was under the BSD+Patents license.

So If React Isn’t BSD+Patents Anymore, What Happened?

While the public discussion about relicensing React ended after the first 4 weeks, apparently it continued within Facebook, for which they should be recognized and commended. This resulted in a somewhat surprising announcement that React will switch from BSD+Patents to the MIT license. At the time of writing, I don’t think this change has been made, but they are planning to implement it soon. As with the RocksDB license change, I’m unsure of the exact legal mechanism being used, especially since this is moving to a less restrictive license (i.e. the copyright holders are giving up more rights). But regardless, we can expect this to be reality soon and the rest of this post assumes Facebook will follow through on the license change.

Awesome, This Means Everything Is Fine Now, Right?

Maybe. Here is where things start getting dicey. The MIT license is generally thought of as a copyright license, just like the BSD licenses. With the switch to it, this would mean Facebook is intending to terminate (or at least no longer rely on) their patent license. But that doesn’t make Facebook’s patents go away.

A quick check on Google Patents shows Facebook currently controls around 5200 patents (not even counting their subsidiaries). Without going through every single one of them, there is no good way to know which, if any, would apply to React or related projects. The posture Facebook initially took around their patent license certainly intimated that they think one or more of their patents does apply, but they don’t have to actually show their hand until/unless they actually file a lawsuit against someone the first time.

So if we are now ignoring the Facebook patent license, there are three scenarios. One is that the whole thing was a bluff (perhaps unintentionally) and there are no Facebook patents which cover React, or equivalently Facebook thinks any patents they do have would be indefensible in a post-Alice world. Second, React will now be covered by a copyright license, but all patents covering React (and here we assume there are some) will not be licensed and Facebook can sue anyone using React at any time. Third, Facebook is relying on a somewhat-controversial reading of the MIT license that says it does provide a patent license.

The first case seems unlikely. The second is downright evil and I have more trust in both the Facebook open-source folks and the React team than that. This leaves us with option three, further bolstered by a tweet from one of the React team. This reading of the MIT license revolves around the phrase “including without limitation the rights to use”. Some people claim given the broad wording of this rights grant, it would include both copyrights and patent rights. But this is the aforementioned dicey bit. To the best of my knowledge, an implicit patent grant this vague and outside of a commercial context has never been tested in court. If this is the goal of the Facebook team, it would also mean they are effectively permanently renouncing those patents, as the implied grant would have no termination rules, even for a lawsuit directly about React. I would very much like to believe this case is our reality, but without a more well-known legal footing, I’m very concerned we may have inadvertently created a scenario two where everyone is actually just infringing all the time.

The announcement of the relicensing from Facebook was very notably absent any discussion of patent rights, and all postings I’ve seen from Facebook folks about this have been very carefully worded to avoided specifically stating what Facebook thinks the patent rights situation will be.

But You Said RocksDB Relicensed And Everything Was Fine?

RocksDB switched to the Apache-2.0 license. Like many newer licenses, it includes specific provisions covering both copyright rights and patent rights (and more). This means that patent rights around RocksDB might actually be more restrictive than React, but they are far more explicit and well understood.

Specifically the Apache-2.0 license uses a fairly standard termination clause, where the lawsuit must claim “the Work or a Contribution incorporated within the Work” is what is infringing. As mentioned earlier, this simplifies lawsuits over the project itself while not totally disarming patent litigation about unrelated things. Beyond just the patent licensing, the Apache-2.0 license also makes a much more specific declaration of which copyright-related rights are being shared, covers trademark licensing, and makes the rules for redistribution clearer.

The fact that Facebook chose the MIT license for React instead of Apache-2.0 sends a signal that they may be trying to hedge their bets here in a way the RocksDB team did not.

Okay, Can I Just Use Preact Instead?

Again, maybe. While copyright law has a concept of “derived works” vs. “non-derived works”, patent law (in this case) does not. Preact is (I think) built as a whitebox reimplementation of many React APIs in a way that Facebook doesn’t hold any copyright over it. But patents don’t care about that, if Preact implements an algorithm or process patented by Facebook it doesn’t matter if it was created independently or not. But since we don’t know which of their thousands of patents might apply, there is no good way to say if Preact would be infringing or not.

Tl;Dr What Do I Do?

At this time, I still think it would be wise for companies to avoid React. If at some point in the future Facebook provides more specific guidance about patent rights this could be easily remedied, but only time will tell on that. I do firmly believe that Facebook and the React team are not being intentionally bad actors in all this, and the open-source community should give them the benefit of the doubt when it comes to incomplete explanations, but at the same time we each need to ensure the legal safety of our own companies and projects.

If you found this discussion of intellectual property issues interesting, I’ve got a whole talk about the basics of IP which can you check out the slides for or come see the talk at PyGotham or DevOpsDays Hartford.

As I said at the start, I am not an attorney so if you have specific questions about React or IP law in general I’m happy to do my best to help but please also talk to a lawyer or your company’s legal department if you have one.


Thanks to Peter Kropf and others for their help with this post.

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