The insurance companies selling through the exchange are the same insurance companies who'd be "losing you", so I don't think that's it. Since businesses aren't subject to being excluded for pre-existing conditions, group plans already have that risk factor built into their pricing. Difference being they discriminate more based on age (55-65 year olds pay 4-5X what a 25 year old pays) than they will be allowed to in January (I think the cap is 3x).