This article, "When Your Insurer Says You're No Longer Covered," in the Washington Post discusses the insurance industry practice of rescission, which occurs when a company cancels a policy because it claims it was misled.  It is unclear how widespread the practice is although the five largest insurers in California have paid $19 million in fines over the last year and a half for wrongly cancelling policies. One of these insurance companies, Health Net, paid a $1 million fine and admitted to paying bonuses to employees for coming up with reasons to try and justify rescinding a policy.