With the perennial tensions between proprietary and open source software (OSS) unlikely to end anytime soon, a $3 billion startup is throwing its weight behind a new licensing paradigm — one that’s designed to bridge the open and proprietary worlds, replete with new definition, terminology, and governance model.
Developer software company Sentry recently introduced a new license category dubbed “fair source.” Sentry is an initial adopter, as are some half dozen others, including GitButler, a developer tooling company from one of GitHub’s founders
The fair source concept is designed to help companies align themselves with the “open” software development sphere, without encroaching into existing licensing landscapes, be that open source, open core, or source-available, and while avoiding any negative associations that exist with “proprietary.”
However, fair source is also a response to the growing sense that open source isn’t working out commercially.
“Open source isn’t a business model — open source is a distribution model, it’s a software development model, primarily,” Chad Whitacre, Sentry’s head of open source, told TechCrunch. “And in fact, it places severe limits on what business models are available, because of the licensing terms.”
Sure, there are hugely successful open source projects, but they are generally components of larger proprietary products. Businesses that have flown the open source flag have mostly retreated to protect their hard work, moving either from fully permissive to a more restrictive “copyleft” license, as the likes of Element did last year and rel=”nofollow” href=”https://grafana.com/blog/2021/04/20/grafana-loki-tempo-relicensing-to-agplv3/”>Grafana before it, or ditched open source altogether as HashiCorp did with Terraform.
“Most of the world’s software is still closed source,” Whitacre added. “Kubernetes is open source, but Google Search is closed. React is open source, but Facebook Newsfeed is closed. With fair source, we’re carving a space for companies to safely share not just these lower-level infrastructure components, but share access to their core product.”
Fair play
Sentry, an app performance monitoring platform that helps companies such as Microsoft and Disney detect and diagnose buggy software, was initially available under a permissive BSD 3-Clause open source license. But in 2019, the product transitioned to a business source license (BUSL), a more restrictive source-available license initially created by MariaDB. This move was to counter what co-founder and CTO David Cramer called “funded businesses plagiarizing or copying our work to directly compete with Sentry.”
Fast forward to last August, and Sentry announced that it was making a recently acquired developer tool called Codecov “open source.” This was to the chagrin of many, who questioned whether the company could really call it “open source” given that it was being released under BUSL — a license that isn’t compatible with the Open Source Initiative’s (OSI) definition of “open source.”
Cramer swiftly issued an apology, of sorts, explaining that while it had erroneously used the descriptor, the BUSL license adheres to the spirit of what many open source licenses are about: Users can self-host and modify the code without paying the creator a dime. They just can’t commercialize the product as a competing service.
But the fact is, BUSL isn’t open source.
“We sort of stuck our foot in it, stirred the hornet’s next,” Whitacre said. “But it was during the debate that followed where we realized that we need a new term. Because we’re not proprietary; and clearly, the community does not accept that we’re open source. And we’re not open core, either.”
Those who follow the open source world know that terminology is everything, and Sentry is far from the first company to fall in its (mis)use of the established nomenclature. Nonetheless, the episode sparked Adam Jacob, CEO and co-founder of DevOps startup System Initiative, to rel=”nofollow” href=”https://x.com/adamhjk/status/1687113805237714944″>challenge someone to develop a brand and manifesto to cover the type of licenses that Sentry wanted to align itself with — similar to what the OSI has been doing for the past quarter century with open source, but with a more commercially attractive gradient.
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