Affiliations with the Letter I
- IBM Research Division -- United States
- Idaho State University -- United States
- Idemitsu Koson Co., Ltd. -- Japan
- Idemitsu Petrochemical Co., Ltd. -- Japan
- Ignace DeBruyne & Associates (ID&A) -- Belgium
- Illinois State Geological Survey -- United States
- Imperial Chemical Industries, PLC -- United Kingdom
- Imperial College -- United Kingdom
- Imperial College London -- United Kingdom
- INA-Industrijanafte -- Croatia
- Indian Agricultural Research Institute -- India
- Indian Association for the Cultivation of Science -- India
- Indian Institute of Chemical Technology -- India
- Indian Institute of Science -- India
- Indian Institute of Science Education and Research -- India
- Indian Institute of Science Education Research (IISER) -- India
- Indian Institute of Technology -- India
- Indian Institute of Technology-Madras -- India
- Indiana University -- United States
- Indiana University Medical Center -- United States
- Indiana University-Purdue University-Indianapolis -- United States
- Indira Gandhi National Open University (IGNOU) -- India
- Industrial Chemistry Research Institute -- Poland
- Industrial Technology Research Institute -- Taiwan
- Industry-University Research Consortium -- Puerto Rico
- Ineos Services Belgium, N.V. -- Belgium
- INEOS USA, LLC -- United States
- InfoChem Gesellschaft für Chemische Information MbH -- Germany
- Information Works -- Germany
- InforSense, Ltd. -- United Kingdom