- California Academy of Sciences
- California Council on Science and Technology
- California Institute of Technology
- California NanoSystems Institute
- California Polytechnic State University
- California State Polytechnic University
- California State University
- Cambridge Centre for Advanced Research and Education in Singapore
- Cambridge University Press
- Canada Foundation for Innovation
- Canadian Astronomical Society
- Canadian Cancer Society
- Canadian Institute for Advanced Research
- Canadian Institute for Substance Use Research
- Canadian Light Source
- Canadian Medical Association Journal
- Canadian Science Publishing (NRC Research Press)
- Cancer Research UK
- CancerCare
- Canterbury Christ Church University
- Canterbury Museum
- Capitol Technology University
- Cardiff University
- Cardiovascular Research Foundation
- Carleton University
- Carlos III University of Madrid
- Carnegie Institution for Science
- Carnegie Mellon University
- Carnegie Mellon University Africa
- Carnegie Mellon University Department of Engineering and Public Policy
- Carnegie Mellon University Electrical and Computer Engineering
- Carnegie Mellon University Materials Science and Engineering
- Carnegie Mellon University Mechanical Engineering
- Carnegie Mellon University's Heinz College
- Carnegie Mellon University, Department of Biomedical Engineering
- Carnegie Mellon University, Department of Chemical Engineering
- Carnegie Mellon University, Department of Civil and Environmental Engineering
- Carnegie Museum of Natural History
- Cary Institute of Ecosystem Studies
- Case Western Reserve University
- Catalan Institute of Nanoscience and Nanotechnology
- Cedars-Sinai Medical Center
- Cell Press
- Cell Transplantation Center of Excellence for Aging and Brain Repair
- Census of Marine Life
- Centenary Institute
- Center for Computational Simulation
- Center for Genomic Regulation
- Center for Vital Longevity
- Central Michigan University
- Central Washington University
- Centre for Addiction and Mental Health
- Centre for Nanoscience and Nanotechnology
- Centrum Wiskunde & Informatica
- CERN
- CGIAR
- Chaffey College
- Chalmers University of Technology
- Chandra X-ray Center
- Chapman University
- Charité - Universitätsmedizin Berlin
- Charles Darwin University
- Charles Sturt University
- Charles University
- Cheetah Conservation Fund
- Cherenkov Telsecope Observatory
- Chiba University
- Children Cancer Hospital Egypt 573z57
- Children's Healthcare of Atlanta
- Children's Hospital & Research Center at Oakland
- Children's Hospital Boston
- Children's Hospital Los Angeles
- Children's Hospital of Philadelphia
- Children's National Hospital
- Children's National Medical Center
- Chinese Academy of Sciences
- CIC biomaGUNE
- Cincinnati Children's Hospital Medical Center
- CIRAD
- CiTIUS (Singular Research Center on Intelligent Technologies)
- City College of New York
- City of Hope National Medical Center
- City University London
- City University of Applied Sciences
- City University of Hong Kong
- Clarkson University
- Clean Arctic Alliance
- Clemson University
- Clemson University College of Engineering and Science
- Cleveland Clinic
- Cleveland Museum of Natural History
- CNRS
- Cognitive Neuroscience Society
- Cold Spring Harbor Laboratory
- Colorado State University
- Columbia Business School
- Columbia University
- Columbia University Irving Medical Center
- Columbia University Medical Center
- Columbia University Quantum Initiative
- Columbia University School of Engineering and Applied Science
- Columbia University's Mailman School of Public Health
- Commonwealth Fund
- Community of European Solar Radio Astronomers
- Complexity Science Hub Vienna
- Concordia University
- Conservation International
- Consumer Wellness Center
- CORDIS
- Corewell Health
- Cornell College
- Cornell Food & Brand Lab
- Cornell University
- Cornell University Food & Brand Lab
- Cosmostatistics Initiative
- Count on Stats
- Coventry University
- Cranfield University
- CREAF
- Creighton University
- Crop Science Society of America
- CSIRO
- CU Anschutz Medical Campus
- CUECR
- CUNY Advanced Science Research Center
- CUNY School of Public Health
- Curtin University
