Back in 2013, Nokia filed a patent for a "Foldable device." The US Patent & Trademark Office (USPTO) granted the patent.

The foldable Nokia phone

Interest in the former king of mobile phones was invigorated lately upon its intent on re-staging a comeback in the mobile industry through HMD Global that is composed of former executives of Nokia of Finland. Perhaps due to this growing interest, Phone Arena dug up a seemingly long-forgotten patent for a "Foldable device" back in 2013. Apparently, Nokia has been filing several patents of the technology as early as 2005.

The image in the Nokia filing looks outdated for today's modern design. It sports a compact mirror or a clam-type look with identical halves connected by a hinge. The opened device feature a single screen panel that folds in half.

According to Pocket-Lint, the filing mentioned that it would be possible to provide a pocket-sized device with a relatively large display. The report mentioned the size possibilities to be 6, 7, or 8 inches or larger.

Considering Nokia has been out of the mobile industry for some time, the patent may not push through or it may take a while for the company to release a foldable smartphone. However, this possibility cannot be discounted knowing that Samsung is high on the speculations list of releasing a folding smartphone later this year.

There are strong indications that a Samsung Galaxy X is bound for release in 2017 that is rumored to feature a design that will allow the device to transform into a 7-inch tablet.

The Nokia foldable battery

Not only was Nokia's seemingly long-forgotten patent for foldable phones been uncovered but another more interesting patent filed in March 2013 was dug up as well. The device is called a "Battery Pack" described as a battery made up of a series of cells that can be folded together.

Accordingly, the battery could be made bigger or smaller depending on the configuration of the handset or quite possibly, any device that would require being powered up for mobile use. The battery is said to be also capable of folding in on itself, Daily Mail reported.

Meanwhile, HMD Global, makers of Nokia teased additional Nokia phones by releasing a video on Facebook. The phone will be announced on Feb. 26, a day ahead of the Mobile World Congress on Feb. 27.