my comment was a response to the comment above, complaining about options and exercise windows offering options, not what you're talking about WRT secondary sales and corporate privacy. The reason we have options and all this weird stuff is indeed tax law. Private companies do not grant equity because it is generally extremely tax disadvantaged to both the employee and the company itself. For instance, the 90 day window is a consequence of ISOs to NQOs, which has a direct tax consequence. I'm not arguing that 90 day exercise window is absolutely better than 10 year exercise window, im just saying that everything is downstream from tax and corporate law.