Hyundai has been granted a patent for a sliding rear door.

Hyundai and Kia have filed a patent application with the United States Patent and Trademark Office (USPTO) for a sliding tailgate for SUVs.

The application, first discovered by a New Nissan Z forum user, describes a truck-mounted tailgate as opposed to a sliding door on a minivan. It slides open on the roof.

The main advantage of this design appears to be space efficiency. The sliding tailgate does not protrude so far up when open, making it easier to use in a garage. Also, people do not need to leave the car when opening and closing it.

However, such sliding tailgates can be difficult to package. Engineers will need to find space for trucks that are likely to have more pronounced curvature than trucks with sliding minivan doors. With the tailgate open, there is also likely to be interference with the roof rack and its cargo.

However, as with all automotive patents, there is no guarantee that Hyundai or Kia plan to add sliding tailgates to their production vehicles. Often, automakers apply for patents simply to protect their intellectual property. But with SUVs making up the bulk of Hyundai and Kia's current lineups and new electric vehicle models on the horizon, one never knows.

Recent patent filings also show some novel tailgate ideas for pickup trucks. Ford applied for a patent for a three-part tailgate, while Rivian applied for patents for telescoping and folding tailgates and an integrated tailgate step.