Hunter Moore, 27, who has been dubbed by some media outlets as "the most hated man on the Internet," was arrested Thursday at his home in Woodland. FBI agents also arrested Charles Evens, 25, of the Studio City area of Los Angeles.
Evens pleaded not guilty in a Los Angeles court while Moore appeared in court in Sacramento but didn't enter a plea, U.S. attorney's spokesman Thom Mrozek said.
Both remained jailed.
A 15-count federal indictment issued this week in Los Angeles charges the men with conspiracy, computer hacking, aggravated identity theft, and aiding and abetting. They could face up to five years in federal prison if convicted.
From 2010 to 2012, Moore ran a website called isanyoneup.com that posted nude and explicit photos, including some submitted to the site by former lovers and spouses without the permission of the people in them. Alongside the photos, Moore included the name and other details of the people depicted.
The photos included an "American Idol" finalist, the daughter of a major Republican donor, and a woman in a wheelchair, according to a 2012 article on Moore in Rolling Stone magazine.
According to the indictment, Evens was paid for providing Moore with nude photos that he obtained by hacking or using other means to accessing hundreds of email accounts.
In an email to Moore, Evens said what he was doing was illegal, and in other emails, Moore offered to pay Evens $200 a week and asked him to use an anonymous PayPal account to avoid detection of the scheme, according to the indictment. Evens was paid as much as $900 at one time, prosecutors contend.
Moore told BBC that he made as much as $20,000 a month in advertising revenue. He ignored cease-and-desist orders and scoffed at challenges to the ethics of his site, although in 2012 he finally sold the website to an anti-cyberbullying organization, saying his notoriety had resulted in people sending him a flood of child pornography and other images.
But he defended the site as well, even though he acknowledged in the 2012 BBC interview that posting the photos could "definitely affect someone's livelihood."
"I just monetize people's mistakes that they made, and it's kind of a shady business. But if it wasn't me, somebody else was going to do it," he said.
In a 2012 interview on CNN's "Dr. Drew" show, a woman who called in to the show chastised Moore for refusing requests to remove naked selfies of her daughter and alleged they came from a hacked account.
"I'm sure she sent the pictures to a million different guys and just ended up on my site just like everybody else," Moore said, although he added that he didn't want to hurt her daughter.
"I'm sorry that your daughter was cyber-raped. But, I mean, now she's educated on technology," he added.