Microsoft could be planning two new flagship phones
Details of the Lumia 850, which will replace the 830, have been leaking out over the past few months and filings in China prove a device that may be the 850 exists.
Regulatory filings for an update to the Lumia 735, most likely called the 750, also leaked alongside the 850.
The two new devices would sit below the Lumia 950, which was announced in October last year.
Microsoft adopted Nokia's numbering system for devices which broadly relate to the status of the device. The Lumia 435 is the lowest-end device while the 950 is the highest and the 640, 735, and 830 sit somewhere in between.
According to leaks, the 850 will be a powerful phone with a 5.7-inch 1080p display, a Qualcomm processor, and 2GB of RAM. No details about the 750 have leaked yet.
Evan Blass, also known as @evleaks, tweeted a photo of an unannounced Microsoft device codenamed "Honjo" which could be the 850.
Mobile World Congress takes place between February 22 and 25. Microsoft has had a big presence in previous years, unveiling several devices, such as the Surface Pro 3 and Lumia 640.