I'm not sure if you would consider these "startups" per se, but I've been at two private companies that had an acquisition or equivalent. Large comparison shop

I'm not sure if you would consider these "startups" per se, but I've been at two private companies that had an acquisition or equivalent. Large comparison shopping site, I joined about 9 months before a majority stake was sold to a private equity group. They took a while to grant my options and by that time they were in talks about the acquisition, so the options were priced at the acquisition price (since once they'd seen an offer, they couldn't price "fair market value" below that). I didn't exercise, since at that price it wasn't going to perform better than any other stock and wasn't liquid. Next time around, I got eleventy billion options in a "startup" around series G or H funding. They got acquired but did not cover the liquidation preferences for investors, so no employees saw a dime. They did hand out some pretty significant bonuses.