It's Official: All Smartphones Sold in California Must Have a 'Kill Switch' Phones manufactured after July 1, 2015 and sold in the state must come equipped with an antitheft device that enables consumers to permanently shut them down.

A California bill that requires smartphone makers to preinstall an antitheft device enabling consumers to permanently shut down their phones (i.e. the 'kill switch') was signed into law yesterday by state governor Jerry Brown.

So it's finally official: All smartphones manufactured after July 1, 2015 and sold in the state, whether in a physical store or online, must be equipped with the kill switch. While similar legislation already exists in Minnesota, California's law goes one step further in that it requires smartphone manufacturers to prompt users to install the feature, making it the default option. Consumers can choose to opt out, if they wish.

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Lawmakers across the country have pressed manufacturers and wireless carriers to include the kill switch on smartphones for some time now. They argue that the feature – which enables consumers to remotely 'wipe' their phones clean -- will dramatically reduce smartphone theft, an increasingly ubiquitous problem. Last year, over 3 million Americans had their smartphones stolen, up from 1.6 million Americans in 2012.

While the CTIA -- the industry trade group the represents leading phone manufacturers and service providers -- was initially against the addition of a kill switch, in April it announced that over a dozen providers including Apple, Google, AT&T, T-Mobile and Verizon would provide free antitheft devices for all smartphones manufactured after July 2015.

Related: Here's One Big Reason Mobile Carriers Don't Want a 'Kill Switch' on Smartphones

But the CTIA is not happy that in California, the kill switch will soon become a default setting. The trade group's argument is that any legislation requiring manufacturers to treat states differently will result in added expenses, expenses that will be passed onto the consumer.

"Uniformity in the wireless industry created tremendous benefits for wireless consumers, including lower costs and phenomenal innovation," Jamie Hastings, the vice president of external and state affairs for the CTIA said in a statement. "State by state technology mandates, such as this one, stifle those benefits and are detrimental to wireless consumers."

Regardless, this is a big win for lawmakers pushing for kill switch bills in their own states, especially if the California legislation is shown to dramatically reduce smartphone theft.

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