What's old is new again? The public markets are too fiddly, so companies seek financing/liquidity on a non-exchange exchange? Investors can buy and sell small

What's old is new again? The public markets are too fiddly, so companies seek financing/liquidity on a non-exchange exchange? Investors can buy and sell small shares of private companies on a "private" market in public view? Seems like the SEC would be grumpy about a public non-public market? What are the listing requirements? Is there an equivalent of the 10-K?