(Posted on KatFans and wanted to share here as it's applicable)
There have been questions on what Conference USA (or even the WAC really) would need to be to constitute a FBS conference. The rules for such can be found below.
As you can make out, there needs to be EIGHT football playing members that also contest at least six men's and eight women's conference sports within said conference. There's a bit more specific (i.e. need three women's team sports), but just want to spell it out for the people that are trying to understand the makeup of the WAC and/or CUSA as it relates to FBS status.
20.02.6 Football Bowl Subdivision Conference. A conference classified as a Football Bowl Subdivision conference shall be comprised of at least eight full Football Bowl Subdivision members that satisfy all bowl subdivision requirements. An institution shall be included as one of the eight full Football Bowl Subdivision members only if the institution participates in the
conference schedule in at least six men's and eight women's conference-sponsored sports, including men's basketball and football and three women's team sports including women's basketball. A conference-sponsored sport shall be a sport in which regular season and/or championship opportunities are provided, consistent with the minimum standards identified by the applicable
NCAA sport committee for automatic qualification. (Adopted: 10/31/02 effective 8/1/05, Revised: 12/15/06)
20.02.6.1 Exception. A Football Bowl Subdivision member institution shall be permitted to count as one of its required six men's sports and one of its required eight women's sports a sport in which its conference does not sponsor or conduct a championship, provided the sport is one in which it participates in another Division I multi- or single-sport conference. Different sports may be counted for men and women. (Adopted: 4/29/04 effective 8/1/05, Revised: 12/15/06)
20.02.6.2 Grace Period. A conference shall continue to be considered a Football Bowl Subdivision conference for two years following the date when it fails to satisfy the eight full Football Bowl Subdivision member requirement due to one or more of its member's failure to comply with the bowl subdivision membership requirements. (Adopted: 4/28/05 effective
8/1/05, Revised: 12/15/06)
NCAA Publications