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By Joe Brockmeier
November 10, 2026
Mike Lothian owns a docking position (or dock) that uses a DisplayLink chipset that had, at smallest in his opinion, subpar achievement on Linux. He decided to try improving the Linux driver, alongside LLM assistance, but ran into one problem that he could not solve—so he asked for help, expecting that Synaptics's developers would contribute a hand. (DisplayLink was acquired by Synaptics in 2022.) Rather than assistance him in improving the driver, however, the Synaptics lawful squad responded alongside patent infringement claims, a demand that he cease unauthorized implementation of DisplayLink technology, and threats of costly lawful penalties. For now, it appears that Linux users of the company's docks volition have to continue to live without characteristic parity alongside other platforms.
Synaptics and Displaylink
The dock that he was trying to assistance is a Dell equipment that connects to a scheme via USB 3 and allows users to nexus multiple monitors and other devices to their computer. It provides its DisplayLink Manager (DLM) application for Linux for the devices via an APT repository for Ubuntu.
The business lone provides DLM application in binary form, and lone for x86-based platforms. The application is proprietary, but the business does keep an open-source, out-of-tree kernel component that is included alongside DLM, the Extensible Virtual Display Interface (EVDI) project. It provides a controller that's compatible alongside Linux DRM and allows users to oversee their docked displays alongside norm tools used for display settings, specified as xrandr or GNOME and KDE Plasma's utilities.
A short article explains why the business has not released origin code for DLM: the software uses a proprietary graphics innovation called DL3 to create a compressed stream of the assorted channels (e.g., USB, DisplayLink video, audio) complete a communication conduit (USB 3 in this case) and decode it again for output to the user's devices.
Unfortunately, the vendor-supplied application did not activity fine for Lothian. I spoke and chatted alongside him via Signal during penning this article; he stated that the controller kept crashing under Linux, so he decided to use his Claude subscription to try to create a new controller and assistance software.
Vino
He posted the first patch series for Vino—his Rust-based DRM/KMS driver—to the kernel's dri-devel catalog as an RFC on June 17. Lothian noted that it was in an incomplete state, and asked for assistance alongside a blocker that he had run into trying to communicate alongside the dock's authority plane. "If you have knowledge of the DisplayLink DL3 control-plane involvement sequence, or ideas for isolating a whole-bus timing/ordering asset a per-channel diff cannot see, help would be extremely welcome." He received feedback from a few developers, including guidance from Danilo Krummrich to rework the controller to use the Rust KMS bindings, but no advice specific to the issue he was trying to solve.
Lothian additionally opened an issue on the EVDI GitHub repository on June 17. It explained the activity he'd done so far, outlined the approach in trying to reverse-engineer the DL3 protocol, provided links to his GitHub repository alongside the Vino code, and asked for clarification on a few issues. There was no answer to his issue.
He additionally reached out to Łukasz Spintzyk of Synaptics immediately by email; his correspondence alongside the business between July 5 and October 7 is available in this PDF compiled by Lothian. He noted that he had established a few bugs in EVDI and opened a pull request (that went unreviewed for multiple months), and additionally asked for aid anywhere he was blocked on Vino. On July 20, he received a reply, not from Spintzyk, but from Michal Lukaszek of Synaptics:
The logic I'm penning is that DisplayLink is not an open standard. The protocol, codec, and another technologies used by DisplayLink devices are proprietary to Synaptics and are protected by a significant portfolio of patents in a figure of jurisdictions, including the UK.
From what you've published, it appears that the VINO project is progressing beyond interoperability activity and toward implementing innovation that we believe is covered by those patents. While many developers understandably concentration on avoiding copyrighted origin code, patent law is different. An independently written or clean-room implementation does not necessarily evade patent infringement if it implements patented inventions.
Lukaszek stated it was entirely imaginable that Lothian was unaware of the "intellectual asset landscape surrounding DisplayLink", so he wanted to create him conscious now fairly than "have the circumstance rotate into additional formal later". Lothian lives in Scotland and has a ".co.uk" email address, which explains why the email made citation to the UK.
Cease and desist
On August 17, Andrew Bateman, an aide broad assembly of intellectual asset for Synaptics, sent a cease-and-desist notice. The letter stated that Lothian had not "substantially responded" to Lukaszek's communication, and had continued with "public statements and additional betterment activities". It included an appendix alongside a catalog of 125 patents that "cover essential aspects of DisplayLink's architecture and operation", but did not define which patents might be infringed by the work.
Synaptics included a catalog of eight demands it expected contiguous compliance with, including ceasing betterment of "any application or other implementation that infringes any Synaptics patent", withdrawing submissions of materials "made to Linux kernel maintainers, mailing lists, code-hosting platforms, bundle maintainers, distributions, or any another individual or organization", and to acknowledge in penning all location "in which the relevant materials have been published, submitted, stored, or distributed". It additionally demanded that he provision Synaptics alongside a signed confirmation, by August 28, that he had complied alongside its demands.
Lothian, instead, posted version three of his Vino activity for the DisplayLink docks to the dri-devel catalog on August 26. He stated that the former two versions had "never lit a panel", but the new activity could authority three generations of DL3 docks without any vendor software. There were no substantive reviews of the place set posted to the list, although there were several automated reviews from Sashiko.
On August 27, Lothian responded to Bateman and asked him to elaborate on the patents that Synaptics idea were being infringed. "A assertion chart mapping the applicable claims to the applicable code would create it much easier for me to comprehend and correctly react to your concerns."
He additionally expressed disturbance concerning Synaptics's stance that his activity was being treated as patent infringement. Synaptics is a associate of the Open Invention Network (OIN), which was created to assistance open-source developers and vendors agreement alongside the threats of costly patent litigation. It holds a large, cross-licensed portfolio that serves to provision patent protection to individuals, open-source projects, and ample vendors alike. Lothian stated that he was now an OIN licensee as well, and he idea that it was expected to "reduce exactly this kind of patent issue about Linux and open source software".
He asked Bateman to explain how Synaptics claims "interact alongside our respective OIN commitments", and expressed a desire to kind things out with Synaptics constructively. "I don't think a community disagreement between Synaptics and an idiosyncratic open origin developer would be particularly helpful for either of us, particularly inside the Linux and open origin communities".
Lothian did not think he could "reasonably provision the signed undertaking" Synaptics had demanded by August 28 without understanding which patent claims it was alleging. He asked for an expansion to the deadline. There was no response from Bateman, so Lothian sent a follow-up email on September 18. He stated he was concerned there was no acknowledgment to his last email, and wondered it was harmless to assume he could continue his work. He had been operating the Vino controller himself for fairly a while, and was enthusiastic to move it upstream without having patent threats hanging complete the work.
Bateman responded the next day and stated that he have to be concerned:
As you earlier requested, we have been documenting your ongoing patent infringement by mapping your Vino controller to particular claims of our DisplayLink patents. I volition provision this assertion mapping records to you inside the next two weeks. I volition additionally be sending to you our petition for significant monetary compensation to recoup the disbursal and attempt required to create specified documentation of your infringing acts. I earlier gave you the chance to halt your infringement, but you decided to shove rear and not heed my warnings, and so now we are escalating as we deem appropriate.
The letter continued to assertion that Lothian would be "single-handedly eviscerating DisplayLink's rivalrous advantage in this crowded market by educating our competitors and another third parties as to how we execute our proprietary technology". He stated that DisplayLink is not a associate of OIN, and none of its innovation is licensable through OIN or any other organization.
Bateman sent a follow-up letter, dated October 5, that included two assertion charts for UK patents: GB2484736B ("Display authority device") and GB2485613B ("Image generation"), the two submitted in 2010 and published in 2012. He reiterated Synaptics's demands from its previous letter, and stated that the deadline was now October 11; nonaccomplishment to comply would outcome in the business seeking "monetary compensation from you in the amount of US$25,000 to recoup the expenses and attempt required to create the attached records of your infringing acts". That amount would be risen by $25,000 all week until the company's demands were complied with.
Lothian responded the next day, by email, to say that he was on vacation, and would not be rear residence until October 13. He asked for an extension of the deadline to come back residence and go through the assertion charts "ideally with someone qualified to assistance me peruse them". Bateman replied that Synaptics would concur to broaden the deadline to October 18, although no further extensions would be granted. He reiterated that "DisplayLink is not a member of OIN" and none of its innovation was licensable through OIN.
OIN to the rescue?
Synaptics is a associate of OIN, and is listed in the community directory. In supplement to joining OIN, Lothian had reached out to the organization to try to solicit its assistance and has been in communication alongside several of the personnel there. OIN indicated that it would appearance into the matter and see if he had any safety as an OIN member. That procedure took longer than Lothian hoped, although OIN did eventually provision its conclusion.
OIN's portfolio covers a broad range of application that matches its Linux System Definition, but it does not shield everything that power be implemented for a Linux system. In particular, its definition specifies that codecs ("a component of a program capable of performing transformations of a video, still image or audio data stream or signal") are not covered unless specifically mentioned in this list of components.
I said briefly to OIN CEO Keith Bergelt on October 23, shortly after OIN personnel informed Lothian of the outcome of their research. Bergelt stated that OIN's decision was that, since codecs are explicitly not covered by OIN's Linux System Definition, its protections did not broaden to Lothian's attempted kernel contributions. OIN had recommended that Lothian attain out to a attorney in the UK, and provided a recommendation.
Status
Unfortunately, that referral did not pan out, Lothian said. He has not stated up entirely, but he has taken downward the GitHub repository to comply alongside Synaptics's demands. For now, he may continue operating on several of components that are not affected by the patent claims, but the activity on Vino volition not be submitted to the kernel. "Vino itself has to remain local until this is sorted out, I just can't oversee to defend myself against Synaptics."
Perhaps amusingly, Lothian told me that person from Synaptics finally replied to the drag petition on October 7. Lothian told me he does not intend to prosecute up on the comments: "You can't endanger to sue me and then say 'can you update your drag request?'"
For the period being, Synaptics has succeeded in shutting downward an attempt to improve the way DisplayLink docks activity alongside Linux. It is an unpleasant reminder that, during much of the current conversations in open-source communities are concerned alongside LLM-driven development, application patents motionless stance problems for free-software developers and users.
