Sea6 Energy is a Bangalore-headquartered company founded in 2010 that farms tropical red seaweed at scale and converts the biomass into products. Its SeaCombine mechanised cultivation system harvests and replants seaweed in deep ocean waters, and a 1 square kilometre mechanised seaweed farm was launched off Lombok, Indonesia in March 2024.

The company holds globally patented products for agriculture, aquaculture, food ingredients, bioplastics, renewable chemicals and biofuel. Commercial products include seaweed-based biostimulants and fertilizers (such as AG Fort and Nutrafert), animal feed and aqua feed ingredients, and food ingredients. Its biofuel work includes a 2024 MoU with HPCL for R&D on converting seaweed biomass into fuels, and an HTL pilot plant inaugurated at HPCL's Green R&D Centre in Bengaluru.

Sea6 sells into India, Indonesia, the United States, Sri Lanka and Vietnam, and has expanded into Spain. Investors include Tata Capital Innovations Fund, Aqua-Spark, Silverstrand Capital, BASF Venture Capital, Potato Impact Partners and PETRONAS' TTV. Reported headcount and revenue vary across sources.