Even as Sony continues to maintain an official silence about the details and release date of one of its most anticipated flagship devices, the Xperia Z4, more leaks continue to surface. After leaked benchmark test results had revealed specifications of the Xperia Z4, new documents have now surfaced related to the Federal Communications Commission (FCC) certificate for a mysterious Sony device codenamed PM-0780.

Sony has been expected to launch the Xperia Z4 in April with a Qualcomm Snapdragon 810 chipset, 3GB RAM, 32GB onboard storage, 20.7MP rear camera, 5MP front-facing camera, and Android 5.0 or 5.1 Lollipop out of the box. There has been a slew of leaks showing purported official press renders and live images of the Xperia Z4. A recent leak had showed the LCD front panel of the Xperia Z4 from different angles and also confirmed its rumored display specifications.

Earlier leaked images of the Xperia Z4 suggested that Sony had maintained its signature OmniBalance design for the smartphone, along with its dust and water resistance capabilities. The display size at 5.2-inch shown in the leaked images was the same as that of its predecessor Xperia Z3, though its screen resolution appeared to have been improved to Quad HD 2,560 x 1,440 pixels with 565 ppi pixel density.

Recently leaked benchmark test results of the Xperia Z4 had suggested that Sony's next flagship would sport a 5.1-inch 1080p display and powered by a 1.9GHz Snapdragon 810 octa-core chipset paired with 3GB of RAM. The Xperia Z4 would have 32GB of internal storage and sport a 20-megapixel rear sensor with LED flash, along with a 5-megapixel sensor front camera. According to the leaked benchmark test results, the Xperia Z4 would also be waterproof and dustproof, and run on Android 5.0.2 Lollipop, with a 3,420mAh battery powering the phone and various connectivity options such as Bluetooth, NFC, GPS and Wi-Fi support.

The FCC has to certify all handsets before they can be sold in the US and there are reports of a Sony device with similar dimensions as the previous Sony Xperia Z3 passing the certification process. The FCC documentation related to Sony's device code named PM-0780 lists six different variants with identical hardware, a non-removable battery and a microSD card slot, supporting a wide range of LTE bands.

The Xperia Z4 has already been approved by the Japanese Internal Affairs and Communication Ministry, and will be reportedly carried by Japanese networks NTT, DoCoMo, KDDI and SoftBank. If the reports of the Xperia Z4 obtaining clearance from the FCC are indeed true, then Sony could launch its flagship device very soon.