Back in 2011, Verizon started throttling 3G data speeds for the 5% of its smartphone customers who used the most data every month, even if those customers had so-called “unlimited” data plans. The company then killed off unlimited data in 2012, but existing plans were conditionally grandfathered in. In what appears to be an attempt to weed out the few remaining unlimited plans, Big V will soon start throttling 4G LTE data speeds for that top 5% of users.

As of now, users with unlimited plans and devices LTE-capable devices didn’t have to worry about being throttled, but the folks at Droid Life recently posted leaked information from Verizon Wireless indicating that this throttling plan would go into effect in Oct. 1.

The documentation obtained by Droid Life includes a notice that the five-percenters are slated to receive starting Aug. 1:

[Verizon] Wireless strives to provide its customers with the best wireless experience when using our network. In 2011, Verizon Wireless launched Network Optimization, which slows the data speeds of its unlimited data subscribers with 3G devices who are in the top 5% of data users when they connect to a cell site experiencing high demand. Effective October 1, Verizon Wireless will expand its existing Network Optimization policy to include its unlimited data subscribers using 4G LTE devices who have fulfilled their minimum contract term. Based on your plan and recent data usage, one or more lines on your account may experience a reduction in data speeds when connected to a cell site experiencing high demand. Customers on MORE Everything or other usage-based data plans are not subject to Network Optimization. For more information about our Network Optimization, please refer to http://www.verizonwireless.com/networkoptimization.

Unlike some “unlimited” plans on other wireless carriers, where heavy users’ data is throttled after reaching a certain monthly threshold, VZW’s “Network Optimization” would not throttle all data for the company’s biggest hogs (currently meaning customers whose monthly data use is around 4.7GB or more); just when said hogs are attempting to use data on a cell site that is experiencing high demand.

For heavy users who are the only data-devourers in the area, this could mean they may see minimal, if any, difference in speeds. Hogs in densely populated areas may see their speeds downgraded much more frequently.

Verizon recently admitted that its LTE service in some metro areas, like New York City, had gotten so congested at times that all customers in an area had to occasionally be knocked down to 3G service.

Five-percenters will remain at risk for throttling until the end of their billing period. If a user drops out of that 5% group by the end of the month, then they are free from restriction — at least until they cross that ever-shifting 5% line.

[via GigaOm]

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