Microsoft has released two versions of its Surface Duo handheld device, each with two displays. But a newly surfaced patent filing indicates that the company has considered, at least, a similar device with three displays.

The filing describes the ability to use a three-screen device in a variety of positions, including a scenario in which the screens are laid flat. That raises the possibility of allowing them to form one large screen collectively.

“Such foldability allows multi-panel display devices to have a larger total display area relative to a similarly-portable single display device, while also allowing for smaller folded dimensions relative to a non-folding display device offering the same display area,” the filing explains.

Microsoft’s Surface Duo and Surface Duo 2 run on Android, and the user experience across the two screens can be less than smooth at times. A third screen would presumably add to the challenge.

This provides a glimpse into Microsoft’s thinking at one point in time, but it’s not clear if the idea of a three-screen device is still on the company’s radar, let alone its product roadmap.

The patent application for the “multi-panel display device” was made public last week by the U.S. Patent and Trademark Office. It was originally filed in June 2020, after Microsoft had announced the original Surface Duo, and three months before it was released in October 2020.

Patently Apple first reported on the filing Monday morning.

Microsoft was previously planning a larger dual-screen Surface Neo device running on a special version of Windows dubbed 10X, but the company indefinitely paused work on that project last year.