The file is part of a multi-part set (e.g., part1.rar , part2.rar ). You need all "pieces" in the same folder to extract the game correctly.
If you are seeing "piece" in the context of a download or error message, it likely means: Stakeholder.Game.rar
Are you trying to find a of a multi-file download? The file is part of a multi-part set (e