Up to 306,000 Anthem Blue Cross customers with insurance policies purchased before Obamacare was enacted will have rate hikes as high as 25%. Additionally, some premiums have already jumped 53% since 2010, not including this latest change.

Last year, when Americans were barraged with healthcare insurance cancellations, state officials warned that holding onto grandfathered policies wouldn’t shield them from significant rate hikes. Unless Anthem can be swayed by California regulators to back down, the increased rates will go into effect on April 1.

Alternatively, the Affordable Care Act offers affected customers an opportunity to buy less expensive insurance. “Many of the members affected here may be eligible for federal subsidies via the Covered California exchange and may have lower premiums if they decide to switch to an Affordable Care Act-compliant policy,” Anthem spokesman Darrel Ng said. However, by changing plans, customers run the risk of losing some benefits and access to their current doctors.

Anthem is not alone in raising premiums on older policies. Earlier this month, Blue Shield of California was scolded by state Insurance Commissioner Dave Jones for an “unreasonable” increase of 10%, on average, for about 81,000 insured customers. At this point in time, however, state regulators cannot avert health insurance rate increases.

Consequently, these events should make November’s ballot initiative which bestows authority on the insurance commissioner to deny excessive rate increases crucial for Californians. Critics of the ballot measure, including insurers, doctors, hospitals, and business groups, insist that if the initiative passes, state exchanges will be undermined and that it will fail to remedy the underlying reasons for the rising premiums.

This 9.8 percent January 1, 2014 rate increase for Blue Shield’s grandfathered policyholders is an average rate increase of 22.6 percent over 12 months. Over the last 24 months, Blue Shield has raised rates on these grandfathered policyholders an average of 32.3 percent.