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Project update

TL;DR

After months of delays, broken promises, and incomplete compliance, the ExpressLRS team has issued a final pre-litigation demand letter through our legal counsel. This represents the final step before initiating formal judicial and administrative proceedings.

What's Happened Since Our Last Update

When we published our October 22nd update, we had reason to be cautiously optimistic. The unauthorized Chinese trademark application had been rejected, the US application's attorney had withdrawn, and the expresslrs[.]dev domain had been taken down. Coming up soon was the October 31st deadline for the demands in our cease and desist letter.

October 31st came and went without a peep, and as we prepared to move to the next phase, on November 2nd the individual behind these filings reached out through an intermediary to negotiate resolution. At that time, the individual agreed to:

  1. Cease all use of the ExpressLRS trademark
  2. Assign the US trademark application to ExpressLRS LLC
  3. Abandon the Chinese trademark application
  4. Transfer the expresslrs[.]dev domain

We extended goodwill, provided an additional 48-hour grace period, and worked with them to facilitate these transfers.

ExpressLRS Progresses Global Protection Thanks To Community Backing

TL;DR

Good news: The unauthorized trademark applications are gradually being rejected, and ExpressLRS LLC is making significant progress protecting the project's identity worldwide.

What's Happened Since Our Last Update

When we published our initial post on October 3rd, we were facing unauthorized trademark applications in China and the United States. Here's where things stand today:

China Application:

The unauthorized Chinese trademark application (No. 84786671) has been rejected outright - in a way that cannot be appealed. This is tremendous news for the team and the community.

United States Application:

Following our cease-and-desist letter sent on October 2nd, 2025, the attorney representing the unauthorized US trademark application has withdrawn from the case entirely. This means if the US Patent and Trademark Office finds any reason to reject the application, the applicant will have to navigate the process without legal representation.

We are now preparing a letter of protest to provide the examining attorney with additional grounds for rejection.

Protect Your Open-Source Project Before It's Too Late: A Legal Horror Story

Running a successful open-source project is one of the most rewarding experiences for a developer community. It’s also a journey full of unexpected challenges - some technical, some human, and, as we’ve recently learned, some legal.

This post is both an update on the status of the ExpressLRS project and a cautionary tale for other maintainers of widely adopted open-source software and hardware: if your project becomes popular, you must take legal steps early to protect its name and identity.

What Happened

Imagine spending years building an open-source project, only to find someone else trying to claim its name. On August 25th, 2025, we were notified that an individual, Christopher Henry Sauer (also known as “Christina Sauer”, “Chris Sauer”, radiomistress) had applied to register ExpressLRS as a trademark in China (Application No. 84786671).

On August 27th, 2025, this individual also registered the domain name expresslrs[.]dev.

On September 8th, 2025, we received further notification of another application from the same individual to register ExpressLRS as a trademark in the United States (Serial No. 99380841).