Ask HN: What disclosure obligations does a private company have to shareholders?

I left a company about 3 years ago, and exercised some options immediately after departure.

Since then they've apparently taken funding (which isn't public anywhere), but I haven't received any correspondence from them (about the funding or anything else). Do they have any obligations to keep me updated on happenings within the company, or are they allowed to keep me completely in the dark until they're a public company or experience a change in ownership?