| AAA Foundation for Traffic SafetyEIN 52-0794368 | Research and Public Policy | DC | $7,776,718Mid-sized | 92.02 |
| Advocates for Children of New JerseyEIN 22-1695034 | Research and Public Policy | NJ | $1,748,049Small | 90.88 |
| Alabama Policy InstituteEIN 63-0809568 | Research and Public Policy | AL | $1,190,677Small | 73.10 |
| Alliance for Aging ResearchEIN 54-1379174 | Research and Public Policy | DC | $1,867,638Small | 89.69 |
| American Academy of Arts and SciencesEIN 04-2103651 | Research and Public Policy | MA | $11,527,301Mid-sized | 91.00 |
| American Association for the Advancement of ScienceEIN 53-0196568 | Research and Public Policy | DC | $107,624,973Large | 87.49 |
| American Constitution Society for Law and PolicyEIN 52-2313694 | Research and Public Policy | DC | $5,891,120Mid-sized | 88.13 |
| American Council for an Energy-Efficient Economy EIN 94-2711707 | Research and Public Policy | DC | $9,400,072Mid-sized | 95.43 |
| American Council on Science and HealthEIN 13-2911127 | Research and Public Policy | NY | $1,729,003Small | 86.87 |
| American Enterprise Institute for Public Policy ResearchEIN 53-0218495 | Research and Public Policy | DC | $55,822,303Large | 87.22 |
| American Institute for Economic ResearchEIN 04-2121305 | Research and Public Policy | MA | $4,008,116Mid-sized | 78.56 |
| American Legislative Exchange CouncilEIN 52-0140979 | Research and Public Policy | VA | $9,056,582Mid-sized | 80.87 |
| American Studies CenterEIN 51-0232804 | Research and Public Policy | VA | $7,739,721Mid-sized | 78.15 |
| American Youth Policy ForumEIN 31-1576455 | Research and Public Policy | DC | $1,439,978Small | 91.69 |
| APhA FoundationEIN 52-6039142 | Research and Public Policy | DC | $1,640,653Small | 73.17 |
| Atlas NetworkEIN 94-2763845 | Research and Public Policy | VA | $11,899,692Mid-sized | 92.57 |
| Be the Change Inc.EIN 26-0402451 | Research and Public Policy | MA | $8,004,215Mid-sized | 79.38 |
| Bermuda Institute of Ocean SciencesEIN 06-0706038 | Research and Public Policy | NY | $15,876,165Large | 94.04 |
| Bigelow Laboratory for Ocean SciencesEIN 01-6006001 | Research and Public Policy | ME | $12,705,375Mid-sized | 96.66 |
| Botanical Research Institute of TexasEIN 75-2198196 | Research and Public Policy | TX | $5,266,139Mid-sized | 85.94 |
| Business Executives for National SecurityEIN 52-1271179 | Research and Public Policy | DC | $5,840,585Mid-sized | 91.72 |
| Californians for Population StabilizationEIN 94-2581509 | Research and Public Policy | CA | $1,049,754Small | 83.06 |
| Capital Research CenterEIN 52-1289734 | Research and Public Policy | DC | $2,844,996Small | 76.58 |
| Carnegie Institution for ScienceEIN 53-0196523 | Research and Public Policy | DC | $100,297,805Large | 87.74 |
| Cary Institute of Ecosystem StudiesEIN 22-3232968 | Research and Public Policy | NY | $13,031,409Mid-sized | 94.32 |
| Center for a New American SecurityEIN 20-8084828 | Research and Public Policy | DC | $9,751,151Mid-sized | 96.54 |
| Center for American ProgressEIN 30-0126510 | Research and Public Policy | DC | $46,765,901Large | 91.15 |
| Center for Climate and Energy SolutionsEIN 54-1892252 | Research and Public Policy | VA | $4,316,838Mid-sized | 84.09 |
| Center for Economic and Policy ResearchEIN 52-2204029 | Research and Public Policy | DC | $1,990,467Small | 89.08 |
| Center for Food SafetyEIN 52-2165893 | Research and Public Policy | DC | $4,380,584Mid-sized | 85.99 |
| Center for Immigration StudiesEIN 52-1449368 | Research and Public Policy | DC | $2,816,435Small | 88.40 |
| Center for Public IntegrityEIN 54-1512177 | Research and Public Policy | DC | $5,208,118Mid-sized | 89.11 |
| Center for Public Interest ResearchEIN 04-2863170 | Research and Public Policy | MA | $3,214,538Small | 71.66 |
| Center for Science in the Public InterestEIN 23-7122879 | Research and Public Policy | DC | $12,565,933Mid-sized | 85.45 |
| Center for Strategic and Budgetary AssessmentsEIN 52-1930922 | Research and Public Policy | DC | $8,653,272Mid-sized | 84.06 |
| Center for Talent InnovationEIN 13-3730312 | Research and Public Policy | NY | $4,340,285Mid-sized | 88.16 |
| Center for the National InterestEIN 26-2117013 | Research and Public Policy | DC | $4,008,865Mid-sized | 89.04 |
| Center for the New EconomyEIN 66-0566096 | Research and Public Policy | PR | $2,308,832Small | 87.15 |
| Center for Urban Renewal and EducationEIN 31-1467594 | Research and Public Policy | DC | $1,671,710Small | 78.59 |
| Center of the American ExperimentEIN 36-3611426 | Research and Public Policy | MN | $2,247,617Small | 77.54 |
| Center on Budget and Policy PrioritiesEIN 52-1234565 | Research and Public Policy | DC | $28,721,352Large | 90.53 |
| Center on Policy InitiativesEIN 33-0824881 | Research and Public Policy | CA | $2,041,680Small | 91.84 |
| Children's AllianceEIN 91-0982879 | Research and Public Policy | WA | $1,472,482Small | 82.23 |
| Civic FederationEIN 36-2170124 | Research and Public Policy | IL | $1,724,422Small | 76.05 |
| Clarion ProjectEIN 20-5845679 | Research and Public Policy | DC | $2,549,070Small | 63.65 |
| CLASPEIN 23-7000150 | Research and Public Policy | DC | $6,942,104Mid-sized | 95.42 |
| Clean Air Task ForceEIN 04-3512550 | Research and Public Policy | MA | $5,368,687Mid-sized | 93.52 |
| Cold Spring Harbor LaboratoryEIN 11-2013303 | Research and Public Policy | NY | $147,631,524Large | 92.80 |
| Colorado Center on Law and PolicyEIN 84-1264154 | Research and Public Policy | CO | $1,154,061Small | 92.33 |
| Commonwealth Foundation EIN 23-2473845 | Research and Public Policy | PA | $2,993,022Small | 88.36 |
| Communications Consortium Media CenterEIN 52-1524972 | Research and Public Policy | DC | $927,021Small | 79.49 |
| Congressional Black Caucus FoundationEIN 52-1160561 | Research and Public Policy | DC | $7,300,039Mid-sized | 89.01 |
| Connecticut Association for Human ServicesEIN 06-0653158 | Research and Public Policy | CT | $1,624,056Small | 86.93 |
| Constitutional Accountability CenterEIN 52-2063854 | Research and Public Policy | DC | $3,469,685Small | 91.86 |
| Council for a Strong AmericaEIN 13-3840271 | Research and Public Policy | DC | $11,660,559Mid-sized | 95.16 |
| Council for National PolicyEIN 72-0921017 | Research and Public Policy | DC | $2,680,790Small | 84.02 |
| Creative CommonsEIN 04-3585301 | Research and Public Policy | CA | $3,342,546Small | 89.05 |
| DemosEIN 13-4105066 | Research and Public Policy | NY | $11,762,460Mid-sized | 87.62 |
| Discovery InstituteEIN 91-1521697 | Research and Public Policy | WA | $5,325,118Mid-sized | 82.97 |
| Drug Policy AllianceEIN 52-1516692 | Research and Public Policy | NY | $14,612,498Large | 76.86 |