Open-weight means the model file's numbers are visible, but unlike open-source software, you cannot see how the model was created or what data encoded those weights.
CJ distinguishes open-weight from open-source: you can see the numbers but not the data or process that produced them. ✦ AI generated
CJ · Syntax · 2026-07-30 · original ↗
starts at this moment · 14:11
When an AI lab makes their model freely available for people to download and use, we call this open weight because we can actually look inside the model file and see all of those numbers or weights. And this is where we can make a clear distinction between open weight and open source. Now, open source is a term that comes from the world of software. It's how we license open source software. But the main difference here is that we can see the weights, the numbers inside of that model file, but we can't actually see how that model was created or what data was used or what actually encoded all of those weight values inside of the file.
verbatim transcript · starts at 14:11
14:11file that has trillions or billions of numbers inside of it. And when an AI lab makes their model freely available for people to download and use, we call this open weight because we can actually look inside the model file and see all of those numbers or weights. And this is where we can make a clear distinction between open weight and open source. Now, open source is a term that comes
14:31from the world of software. It's how we license open source software. But the main difference here is that we can see the weights, the numbers inside of that model file, but we can't actually see how that model was created or what data was used or what actually encoded all of those weight values inside of the file. Now, what you actually do with that model file itself is also under a
14:54license and sometimes a terms of service. And that's where this is closer to open source software. And in this scenario, models have a license or a terms of service. sometimes even an open- source license that dictate what can be done with their models once you've downloaded them. For instance, DeepSeek models are released under the MIT license. And this means that anyone is allowed to download, run, and even
15:16profit from their models. So, as a US citizen, you could start your own AI company that basically just runs fine-tuned or tweaked DeepSeek models. You don't even have to have an AI lab or billions of dollars. You just need to rent the infrastructure and now you've got a business selling custom access to custom AI models. But in contrast to that, there are models like Llama from Meta that have a license which cap free
15:40commercial use at 700 million monthly active users and a competitor restriction clause that blocks entire industries. So while these llama models are open weight, we can see all of the weights inside of them. We can't necessarily start a really large business using them. And if we work in certain industries, we're not really supposed to use those models either because that would be violating their terms of service. Now, the other thing