It contains the cryptographic keys and system instructions required to decrypt and launch Nintendo Switch game files on a PC.

The file is a proprietary firmware file used by Nintendo Switch emulators (such as Ryujinx or Yuzu) to mimic the console's operating environment. File Overview

A legitimate v15 BIOS file should be small (usually a few kilobytes for keys or several megabytes for firmware) and should never require you to "run" an application to install it.