| Institution of Engineers, Indonesia | Academic & Science |
| Persatuan Insinyur Indonesia | Academic & Science |
| Integration Engineering Incorporated | Academic & Science |
| ICP Electronics Inc | Academic & Science |
| Iwashita Engineering Inc | Academic & Science |
| Institute for Electric Innovation | Academic & Science |
| Infrastructure Engineering Inc | Business |
| Independent Environments Inc | Business |
| Indiana Energy, Inc. | Business |
| Institute for Educational Initiatives | Community |
| Interrupt Enable Input | Computing |
| Iran Electronics Industries | Electronics |
| International Electronics Inc | Electronics |
| Interstate Electronics Inc | Electronics |
| Intertemporal Efficiency Index | General |
| Information Element Identifier | General |
| Intuitive Ethical Introvert | General |
| Instructional Enhancement Initiative | General |
| Integrity Excellence and Innovation | General |
| Intercontinental Export Import | General |
| iţiativa Erasmus Iaşi | General |
| Intercultural Engagement and Inclusion | General |
| Integral Electronic Ignition | General |
| Intercontinental Events Inc. | General |
| Institution of Engineers India | Governmental |
| Institute for Emerging Issues | Governmental |
| Individual Employment Income | Governmental |
| Institute for Engineered Interfaces | Governmental |
| Institute for Economic Inquiry | Governmental |
| Idiopathic Environmental Intolerance | Governmental |
| Information Economy Initiative | Governmental |
| Intensive English Institute | Governmental |
| Innovation and Entrepreneurship Institute | Governmental |
| Institute for Entrepreneurship and Innovation | Governmental |
| International English Institute | Governmental |
| International Epidemiology Institute | Governmental |
| Institution of Engineers of Ireland | Governmental |
| Institute for Engineering Interface | Governmental |
| Illinois Eye Institute | Governmental |
| International Educators Institute | International |
| International Educators of Illinois | International |
| International Enterprises Inc | International |
| Ion Exchange India | International |
| Intensive English for Internationals | International |
| International Enamellers Institute | International |
| Idiopathic environmental intolerances | Medical |
