What would this even look like? An 83b election is something I file with the IRS. Are you suggesting a company might have me sign a contract committing me to not file an 83b election?
How would they ever find out if I did file, and why would they care?
My understanding is that 83b applies to stock, not options, so you have to first exercise the options and hold unvested stock. That requires early exercise.
It's been a possibility in my options contracts. However, the company must agree to it, cash your exercise check, and send the necessary paperwork to the IRS. If they choose not to cooperate, you're out of luck.
How would they ever find out if I did file, and why would they care?