It's not proprietary, they (tax companies) just want you to think that. It is very murky though, but you can fill out and file the proper forms yourself if you

It's not proprietary, they (tax companies) just want you to think that. It is very murky though, but you can fill out and file the proper forms yourself if you know what you're doing. Apparently, even the models last filing season did a great job. My uncle has been an accountant and done a lot of the family's taxes for decades. He did a parallel comparison and the llm did it perfectly. The models have improved since then as well. Of course, if you're (imo rightly) concerned with your data, you'll have to run them locally.