The HPPA Act of 1996 protected those in group plans (i.e. employer provided insurance) who had pre-existing conditions but it did not cover the small individual market. Just over half of US states enacted various types of pre-X protections for the individual market.
The ACA extended pre-X coverage protection to all market participants including the small individual market. Most people do not understand this as the ACA marketing, in 2010, was misleading and implied no one had pre-existing condition protections pre-ACA, which is not true.
Medicare/Medicaid have no pre-existing condition exclusions, and they account for about 38% of the market. Supplemental “medigap” plans have no pre-existing condition exclusions at first Medicare sign up but can have exclusions if Medigap is added later (with some exceptions).
