The short answer is no, not in the United States and not for products sold by a US Manufacturer. The US Federal Trade Commission has very specific consumer protection laws, as outlined by the FTC's Magnuson-Moss Warranty Act of 1975.
This act outlines several key points, including the basic consumer protection that a manufacturer cannot void the warranty on components that are not directly affected by the installation/placement of after-market upgrade components. In fact, Apple and other hardware manufacturers support certain end-user upgrades, such as replacing memory (RAM), hard disk drive (HDD), or solid state drive (SSD), and even include basic instructions with their user manual or via their online support pages.
Reasonably speaking, if you properly install your memory (RMA), hard disk drive (HDD), or solid state drive (SSD) upgrade, following OWC's how-to installation video for your specific Mac, your warranty should not be voided. It is wise however, to know your skill and comfort level in performing this type of mechanical procedure. Therefore we highly recommend viewing the appropriate memory (RAM), hard disk drive (HDD), or solid state drive (SSD) installation video to determine if you or a certified technician should perform the upgrade. While OWC cannot guarantee the actions of the original manufacturer, we encourage our consumers to familiarize themselves with his or her rights.