Huawei are one of the largest Chinese smartphone manufacturers in the world. The company has been on something of a charm offensive for the last eighteen months, introducing a number of devices across the world in a serious attempt to sell products outside of the China and other Asian regions. These new products include a range of Honor smartphones, the Huawei Watch, which runs Android Wear, a range of new, powerful Kirin chipsets, courtesy of its semiconductor business, HiSilicon, and the premium Google Nexus device, the 6P. Huawei made its intentions known in early 2015: it wanted to push its technology and products around the world. The company has managed this: Huawei, and its associated brand names such as HiSilicon, Honor and Kirin, are now much better recognized across the world. One of the reasons why Huawei has been able to extend its product family across the world is because it has spent years establishing a patent portfolio with which to defend its technologies. We've already seen Huawei tackle other smartphone manufacturers in the industry but yesterday, Huawei seemingly raised the stakes and made a complaint about T-Mobile US' network.
Huawei is claiming that T-Mobile has used their patented technology, associated with 4G technologies as defined by the 3GPP release 8 and later. This covers all LTE technologies together with the higher performing 3G networking technologies that T-Mobile USA traditionally called 4G, such as DC-HSPA (which allows a maximum data download rate of 42 Mbps). Huawei's filing states that T-Mobile would be unable to "operate its core wireless network without the use of Huawei's 4G Wireless Network Essential Patents," which could make things interesting for T-Mobile. You can read the complaint in full at the source link below.
Huawei's documentation appears to sound as though the Chinese company has explored every other possibility before filing a lawsuit. Huawei state that they first tried to talk with T-Mobile US about their wireless patents a little over two years ago, in June 2014. Huawei tried to enter a non-disclosure agreement with T-Mobile before the discussions, but America's third largest carrier refused. Earlier in the year, Huawei filed a patent infringement suit against T-Mobile but stated that it wanted to start discussions. At this point, T-Mobile US agreed to enter a non-disclosure agreement. However, Huawei's report states that the manufacturer and carrier then spent five months discussing the terms of the non-disclosure agreement and ultimately the licensing offer, before rejecting Huawei's "FRAND" offer (fair, reasonable and non-discriminatory). Huawei's intention is to persuade the court that it has met its FRAND commitment by offering terms to T-Mobile, and to declare T-Mobile an unwilling licensee. At the time of writing, T-Mobile US have yet to (publicly) respond, but we will keep you notified of any developments.