Video Seal is an open-source video watermarking tool developed by Meta that efficiently embeds imperceptible yet robust watermarks into videos. It uses a novel "temporal watermark propagation" technique to reduce processing time while maintaining effectiveness against various video manipulations. Content creators, media companies, and others concerned with video authenticity and ownership can use Video Seal to protect their content, verify its origins, and combat deepfakes, making it a valuable tool in an era of increasing digital content manipulation.