In general the concept is that related buyers have a right to be informed but anyone else in the market. So if you were to buy stake in a private company during that youd have the right to the books during that sale and covering that is fraud.
Kind of like how buisnesses would have no right to know how much equity i have unless it was relevent to any actual agreement.
Not saying i think its right way or better but i dont see total transparency of details not related to a direct sale and the partipants to be necceray for a market to be "free".