A new state law requires Internet service providers (ISPs), like Comcast and CenturyLink, to treat the delivery of all data equally no matter which company originates it. The bill, passed with broad bipartisan support in February and signed by Gov. Jay Inslee in March, had a provision to kick into effect the moment the FCC finalized its order to eliminate the requirement for neutral Internet service, which occurred today.

Washington’s new net neutrality law is the first of its kind to both pass and take effect. It corresponds closely to the previous federal rule, barring ISPs from blocking or throttling the bandwidth on any legal content, service, app, or device, subject to reasonable network management.

ISPs also can’t engage in prioritizing traffic for money. For instance, an ISP can’t allow one streaming video service to pay for a faster lane than is standard, to provide an ostensible better experience to the service’s customer.

Corporate advocates of net neutrality—which include most Internet-centered firms, like Google, Facebook, Spotify, and Netflix—argue that eliminating net neutrality would reduce competition and innovation, and allow ISPs to offer their own services at an advantage. It would also increase costs for consumers, as content providers were forced to pass along fees. Startups without the resources to pay to remove throttling or for faster lanes might be unable to ever compete with established players.

The law doesn’t prohibit so-called zero rating, in which companies providing a service pay the costs of delivering data to an ISP’s customer. This is typically used by streaming audio and video services for mobile devices to provide a benefit to their subscribers by reducing cellular data use. (Many cellular carriers have unlimited data plans, but they throttle from high-speed 4G LTE service to a trickle after a subscriber consumes a certain amount of data in a given month.)

Oregon also enacted a net neutrality law, signed in April and that goes into action in 2019, but it only restricts state agencies and other public bodies from contracting with network providers that don’t meet non-discriminatory provisions. Governors in five states—Hawaii, Montana, New Jersey, New York, and Vermont—have signed executive orders similar to Oregon’s law covering service to the states. Legislation in other states, like California and New York, is still proceeding and likely to be as strict as Washington’s.

The FCC is almost certain to challenge Washington as the agency asserted preemption, in which federal laws have precedent over state ones. ISPs may also sue the state, although no lawsuits have yet been reported. ISPs formerly made the case that net neutrality failed to allow them to recoup the costs incurred in linking their networks to content providers, often citing Netflix, which consumes a double-digit percentage of all Internet traffic in the United States during peak hours.

Washington’s net neutrality rule casts enforcement as a provision of consumer protection in an attempt to avoid stepping into federal telecommunications statutes. Washington’s Gov. Inslee said at the signing in March, “The states have a full right to protect their citizens.”

In the meantime, some ISPs have promised in the absence of the federal net neutrality rules to not slow data or block it, and with state laws in flux and a federal showdown possible, it’s unlikely any would push the envelope at present. The FCC’s new rules also require ISPs disclose publicly any blocking or throttling they engage in, as well as reveal any deal in which they prioritize traffic.