The phrase is a specific search term often used by students and researchers looking for unrestricted access to the Aggarwal and Malcom (often misspelled or shorthand for various academic texts) resources, or more commonly, the AGMA (American Gear Manufacturers Association) standards and technical papers.
These standards are intellectual property. Unauthorized distribution hurts the organizations that fund the research to keep these standards safe. How to Access Engineering Standards for Free (Legally)
By following the legal routes, you ensure your designs are based on the most current safety standards while protecting your hardware from digital threats.