The pharmacist here in Seattle sued her employer, Bartell Drugs (a local pharmacy chain) on behalf of herself and other female employees, charging sex-discrimination. Bartell Drugs employees are covered under a PPO (not HMO) programme through Regence BlueShield. The pharmacist won, and now all Bartell's employees are provided with BCP coverage.
The salient point here is, EMPLOYERS DETERMINE DRUG BENEFITS. Insurers do not. The insurer or insurance broker simply offers a list of plans to the employer, at varying prices, and the EMPLOYER decides how much the company is going to spend--and that decides what drugs end up on your formulary and what drugs you have to pay for out-of-pocket. Some plans--like mine--don't even HAVE a formulary. My husband's employer chose a "Cadillac" type plan for their employees, and thus ANY drug prescribed by a licenced physician--including BCP and diet drugs--is covered under the pharmacy benefit. This is why the pharmacist sued her EMPLOYER, not Regence BlueShield; Regence was happy to provide BCP benefits if Bartell's was willing to pay for it.
Sorry to disappoint, but there are no backroom-deals between Pfizer, Schering-Plough, or whatever and insurers. The bottom line is, how cheap is your employer? Most employers, and employees, find it easier to blame the big 'ol insurance companies when the pharmacy or hospital bill comes, rather than admit to the reality, which is that YOUR EMPLOYER SCREWED YOU.
Incidentally, I worked at a multispecialty clinic that put out a newsletter quarterly for its employees. One quarter, we got the happy news that "although insurance premiums have risen, the [clinic name] has been able to avoid passing on these costs to employees, with little change in benefits." Guess what that "little change" was? Yup. Our drug copay leapt from $5.00 to $35.00 per Rx. The clinic had avoided DIRECTLY passing on the costs to employees, but any employee who had to have any prescription filled paid for that decision in a very direct way.