About once a month, on a Friday or Saturday night, the Silicon Valley Technorati gather for a drug-heavy, sex-heavy party. Sometimes the venue is an epic mansion in San Francisco’s Pacific Heights; sometimes it’s a lavish home in the foothills of Atherton or Hillsborough. On special occasions, the guests will travel north to someone’s château in Napa Valley or to a private beachfront property in Malibu or to a boat off the coast of Ibiza, and the bacchanal will last an entire weekend. The places change, but many of the players and the purpose remain the same.

The stories I’ve been told by nearly two dozen people who have attended these events or have intimate knowledge of them are remarkable in a number of ways. Many participants don’t seem the least bit embarrassed, much less ashamed. On the contrary, they speak proudly about how they’re overturning traditions and paradigms in their private lives, just as they do in the technology world they rule. Like Julian Assange denouncing the nation-state, industry hotshots speak of these activities in a tone that is at once self-congratulatory and dismissive of criticism. Their behavior at these high-end parties is an extension of the progressiveness and open-mindedness—the audacity, if you will—that make founders think they can change the world. And they believe that their entitlement to disrupt doesn’t stop at technology; it extends to society as well. Few participants, however, have been willing to describe these scenes to me without a guarantee of anonymity.

If this were just confined to personal lives it would be one thing. But what happens at these sex parties—and in open relationships—unfortunately, doesn’t stay there. The freewheeling sex lives pursued by men in tech—from the elite down to the rank and file—have consequences for how business gets done in Silicon Valley.

Sex Parties of the Tech and Famous

From reports of those who have attended these parties, guests and hosts include powerful first-round investors, well-known entrepreneurs, and top executives. Some of them are the titans of the Valley, household names. The female guests have different qualifications. If you are attractive, willing, and (usually) young, you needn’t worry about your résumé or bank account. Some of the women work in tech in the Bay Area, but others come from Los Angeles and beyond, and are employed in symbiotic industries such as real estate, personal training, and public relations. In some scenarios, the ratio of women to wealthy men is roughly two to one, so the men have more than enough women to choose from. “You know when it’s that kind of party,” one male tech investor told me. “At normal tech parties, there are hardly any women. At these kinds of party, there are tons of them.”

I believe there is a critical story to tell about how the women who participate in these events are often marginalized, even if they attend of their own volition. One female investor who had heard of these parties before I approached her told me, “Women are participating in this culture to improve their lives. They are an underclass in Silicon Valley.” A male investor who works for one of the most powerful men in tech put it this way: “I see a lot of men leading people on, sleeping with a dozen women at the same time. But if each of the dozen women doesn’t care, is there any crime committed? You could say it’s disgusting but not illegal—it just perpetuates a culture that keeps women down.”

To be clear, there is a wide range of parties for experimental sexual behavior. Some, devoted entirely to sex, may be drug- and alcohol-free (to encourage safety and performance) and demand a balanced gender ratio. Others are very heavy on drugs and women and usually end in group “cuddle puddles,” a gateway to ever-so-slightly more discreet sexual encounters.

Men show up only if directly invited by the host, and they can often bring as many women as they want, but guys can’t come along as plus-ones. (That would upset the preferred gender ratio.) Invitations are shared via word of mouth, Facebook, Snapchat (perfect, because messages soon disappear), or even basic Paperless Post. Nothing in the wording screams “sex party” or “cuddle puddle,” in case the invitation gets forwarded or someone takes a screenshot. Besides, there’s no need to spell things out; the guests on the list understand just what kind of party this is. Women too will spread the word among their female friends, and the expectations are hardly hidden. “They might say, ‘Do you want to come to this really exclusive hot party? The theme is bondage,’ ” one female entrepreneur told me. “ ‘It’s at this V.C. or founder’s house and he asked me to invite you.’ ”

“IT’S VERY RISKY—ONCE YOU’RE IN THAT CIRCLE, ONCE YOU DECIDE YOU WANT TO PLAY THE GAME, YOU CAN’T BACK OUT.”

Perhaps this culture is just one of the many offshoots of the sexually progressive Bay Area, which gave rise to the desert festival of free expression Burning Man, now frequented by the tech elite. Still, the vast majority of people in Silicon Valley have no idea these kinds of sex parties are happening at all. If you’re reading this and shaking your head saying, “This isn’t the Silicon Valley that I know,” you may not be a rich and edgy male founder or investor, or a female in tech in her 20s. And you might not understand, anyway. “Anyone else who is on the outside would be looking at this and saying, Oh my God, this is so fucked up,” one female entrepreneur told me. “But the people in it have a very different perception about what’s going on.”