Foothill Ranch, California in the context of Lake Forest, California

Red Digital Cinema is an American camera manufacturer specializing in digital cinematography headquartered in Foothill Ranch, California. The company became a subsidiary of Nikon in 2024.

Red has studios in Hollywood, Los Angeles, and has offices in London and Beijing, as well as a retail store in Hollywood. Additionally, Red has various authorized resellers and service centers worldwide. The company was founded by Jim Jannard in 2005 out of a side interest in digital photography, previously Jannard had founded the eyewear company Oakley which shares a similar industrial design language.

Oakley, Inc. is an American company headquartered in Foothill Ranch, California, which is an autonomous subsidiary of Luxottica. The company designs, develops and manufactures sports performance equipment and lifestyle pieces including sunglasses, safety glasses, eyeglasses, sports visors, ski/snowboard goggles, watches, apparel, backpacks, shoes, optical frames, and other accessories. Most items are designed in house at their head office, but some countries hold exclusive designs relevant to their market. Oakley currently holds more than 600 patents for eyewear, materials, and performance gear.

TAE Technologies, Inc., formerly Tri Alpha Energy, is an American company based in Foothill Ranch, California developing aneutronic fusion power. The company's design relies on an advanced beam-driven field-reversed configuration (FRC), which combines features from accelerator physics and other fusion concepts in a unique fashion, and is optimized for hydrogen-boron fuel, also known as proton-boron or p-B. It regularly publishes theoretical and experimental results in academic journals with hundreds of publications and posters at scientific conferences and in a research library hosting these articles on its website. TAE has developed six generations of original fusion platforms, with a seventh in development as of 2025. It aims to manufacture a prototype commercial fusion reactor by 2030.