The blaze in Glendora destroyed five homes and damaged 17 others. Five firefighters and another person were injured.
Clifford Henry, Steven Aguirre and Jonathan Jarrell were indicted on six federal counts of illegally setting and failing to control an unauthorized campfire. They've been ordered back in court on Feb. 11.
They each could face 12 years in prison. The indictment supersedes earlier federal charges. The three remain jailed and have not entered pleas.
Authorities say the men set a campfire in the Angeles National Forest on Jan. 16 during Santa Ana winds and extreme fire danger. The men said a gust blew burning paper into some brush, sparking a 3-square-mile blaze.
The fire was finally declared 100 percent contained on Friday - more than two weeks after it broke out.
The Associated Press contributed to this report.