Peter Moshou, 37, of Auburndale, Fla., could face up to three years in prison for violating the federal CAN-SPAM Act. Prosecutors say Moshou sent millions of unsolicited commercial e-mails using Atlanta-based EarthLink's network.
The messages, sent throughout 2004 and 2005, were about brokerage services for people interested in selling their timeshares.
EarthLink filed a civil lawsuit against Moshou in January after the company detected a massive influx of spam in its system and later handed its investigation over to federal prosecutors.
On Thursday, as Moshou awaited a first hearing with U.S. Magistrate Gerrilyn Brill, he did not seem like a man who could face prison time and a fine of up to $350,000 for sending the spam e-mails. Wearing a striped shirt and tennis shoes, Moshou idly chatted with prosecutors about spam attempts, laughing as one joked about spamming ploys.
But when the court hearing began, no one on either side of the counsel table was laughing.
"Internet spam is more than just an annoyance," said U.S. Attorney General David Nahmias. "It is criminal."
This marks the second high-profile prosecution EarthLink has helped secure. After the Internet service provider in 2003 won a $16.4 million judgment against Howard Carmack, the so-called Buffalo Spammer, the company turned its evidence over to New York prosecutors.
In May, Carmack was sentenced to up to seven years in prison for sending 850 million junk e-mails through accounts he opened with stolen identities.
After the hearing, Moshou and his attorney went to the chambers of U.S. District Judge Richard Story to schedule a time when he can enter his guilty plea.