then eventually became the manager of the whole center. When the fraud
group operations moved to Omaha, that made it a lot cheaper for us to run. She
was working on the human management part—all the investigators—and I
would be supplying her with software. Between those things, we got fraud
pretty well under control in about a year.
Livingston: So the fraud solution was a combination of humans and software?
Levchin: Depending on who you ask. I think Sarah feels that it’s probably more
humans and the coders think it’s more technology. It’s...

Livingston: Did you patent this technique?
Levchin: I didn’t really want to patent it because, for one, I don’t like software
patents, and, two, if you patent it, you make it public. Even if you don’t know
someone’s infringing, they will still be getting the benefit. Instead, we just
chose to keep it a trade secret and not show it to anyone.
After a while, IGOR became well known to the company, like all the other
tools that we had built early on. We had patented some of it, and some of it we...

you are a very safe user. But by then you are also not a user, because for
every step you have to take, the dropoff rate is probably 30 percent. If you take
ten steps, and each time you lose one-third of the users, you’ll have no users by
the time you’re done with the fourth step.
The point is, the startups didn’t realize there was this risk. We didn’t really
realize there was this risk component either when we started. But we were just
lucky enough . . . Maybe I should be...

anyone with a substantial public visibility announcing that they are suddenly
bleeding out $10 million a month in fraud would send serious shocks through
the investor base. But I think, even if they did that, it’s likely they wouldn’t have
been successful because—we had talked to a lot of them both as a potential
acquirer and as partnership potential—none of them had actually ever gone to
the sort of stuff that we did for our anti-fraud work.
Max Levchin 11
The default of how you do these things is very powerful, if you’ve...

20,000 new active users every day. The transactional growth is exponential
because people are sticking around. It’s not like people came in, did one thing,
and left. They came in, did one thing, and stayed. And they kept doing more.
Livingston: Was the growth viral?
Levchin:We built the system to be viral from day one. The idea was: I can send
you the money, even if you aren’t a member. If I send you $10, you get an email
saying, “You have $10 waiting for you. Sign up, and you can take it.” That’s...