"Preexisting Conditions" isn't always fully understood by many people. Here are some examples of how it used to work before Obamacare:

1. A person has some health condition and wants to purchase their own private medical coverage. So they go through underwriting, medical exam, etc... Based on their condition, they can be denied insurance coverage due to risk or insured at a higher rate. People with chronic illnesses could never pay in more than they draw, so insurance companies will deny coverage.

2. A new employee getting GROUP insurance coverage through their employee at either their hire date or an existing employee getting coverage for the first time at open enrollment period: Typically there is a 6 month to 12 month waiting period for coverage of preexisting conditions. They get health insurance so coverage isn't denied, but any preexisting conditions are carved out for a period of time. Once the waiting period is over, then their preexisting conditions do become covered.

3. A person who has insurance coverage and has had it long enough to serve any waiting period for preexisting conditions wants to get a new policy....private or employer provided. Often they can transfer from one to another without having to deal with the preexisting conditions issue....Transfer of Credible Coverage rules and COBRA rules apply. I know this is the case swapping from one employer to the next as long as the regs are followed (typically no more than a 60 day gap in credible coverage allowed to transfer into new coverage and not have to be subject to preexisting conditions clause).

This is how it used to work. Private coverage was much more strict on preexisting conditions that was employer based coverage.

My mom has Type 1 Diabetes since she was 10-12 years old and she's never been without health insurance because she was always under an employer health plan...even now as retired with pension insurance plan and Medicare.

My 17 year old son has polycystic kidney disease since he was young. He has coverage under my employer based health insurance with 3 different companies since his birth. As long as my coverage stayed current he'd have coverage. Once he is on his own, for him to ever get insurance under the old way/old regs, would be to take his certificate of credible coverage from my coverage now and transfer that to his new coverage through an emplyer of a private plan that accepted that as "waiving the preexisting conditions" clause.

Now with the Obamacare rules, people who would normally be either denied coverage due to chronic health conditions or high risk or be made to serve a 6-12 month waiting period for such conditions no longer have to do that anymore. That sounds really good on the surface because people are getting approved for healthcare insurance.

But there is a downside. Sometimes a portion of these people can and do get coverage then bump to a new plan for treatment, get coverage, get really expensive treatment, then jump ship somewhere else. This leave the insurance companies EXPOSED and increases the financial risk. This equates to increase premiums for everyone to cover these realized losses or potential losses.