X-Factor #40 was published by Marvel Comics on April 1, 2009, as part of a series that began in 2006. Peter David writes, and art comes from David Yardin, Jeromy Cox and Nathan Fairbairn. This 36-page issue features Madrox, Layla Miller, Multiple Man, John Maddox and Susan Maddox, among 8 characters cataloged on VerseDB.