| 1 | Municipal Employee Pension FDGov | $3,014,848,176 | 240 | 1 |
| 2 | Cook County TreasurerGov | $1,840,920,574 | 66 | 1 |
| 3 | Policemens a & B Fund | $1,410,477,739 | 262 | 1 |
| 4 | Amalgamated Bank of Chicago | $1,317,947,108 | 492 | 1 |
| 5 | Zions Bank | $858,852,583 | 61 | 1 |
| 6 | Nationwide Retirement Solution | $824,738,719 | 461 | 1 |
| 7 | Bank of New York Trust | $768,529,171 | 121 | 1 |
| 8 | Municipal Employees Annuity and Benefit Fund of Chicago | $702,129,889 | 11 | 1 |
| 9 | Firemens Annuity Benefit Fund | $662,442,132 | 246 | 1 |
| 10 | Blue Cross & Blue Shield | $609,983,746 | 68 | 1 |
| 11 | State of Illinois Treasurer's OfficeGov | $531,099,387 | 14 | 1 |
| 12 | U S Bank N a | $505,614,504 | 170 | 1 |
| 13 | Bank of Ny Midwest Trust Co | $437,320,558 | 209 | 1 |
| 14 | U.S. Bank01 National.association | $344,572,884 | 35 | 1 |
| 15 | Laborers & Retirement Board | $330,367,034 | 116 | 1 |
| 16 | Chicago Transity Authority.Gov | $320,478,172 | 78 | 3 |
| 17 | Loevy & Loevy Attorneys at Law | $235,729,100 | 154 | 1 |
| 18 | Chicago Patrolmen's Fcu | $202,197,236 | 96 | 1 |
| 19 | F.H. Paschen S.N. Nielsen & Associates, LLC | $177,580,825 | 177 | 5 |
| 20 | F.H. Paschen, S.N. Nielsen & Associates, LLC | $172,558,700 | 261 | 4 |
| 21 | Board of Education of the City of ChicagoGov | $160,376,161 | 102 | 5 |
| 22 | Public Building Commission ChicagoGov | $144,354,604 | 78 | 2 |
| 23 | Caremark Inc | $129,571,343 | 54 | 2 |
| 24 | Chicago Firemans Assn Credit | $129,319,895 | 96 | 1 |
| 25 | Department of FinanceGov | $125,646,286 | 114 | 1 |
| 26 | Usi Insurance Services LLC. | $122,556,140 | 98 | 2 |
| 27 | Turner Paschen Aviation Partners | $122,314,824 | 87 | 1 |
| 28 | Aecom Hunt / Clayco, a Joint Venture | $121,981,274 | 61 | 1 |
| 29 | U.S. Bank | $116,780,438 | 36 | 1 |
| 30 | PNC Bank | $115,431,370 | 94 | 1 |
| 31 | Clark-W.E. ONeil JV | $105,189,358 | 52 | 1 |
| 32 | Constellation Newenergy Inc | $92,249,309 | 35 | 1 |
| 33 | Laborers and Retirement Board Employees' Annuity Benefit Fund | $74,894,983 | 6 | 1 |
| 34 | CDW Government, LLC. | $73,262,325 | 812 | 2 |
| 35 | Bigane Paving Company | $71,875,951 | 228 | 2 |
| 36 | Pan-Oceanic Engineering Co Inc | $69,837,486 | 100 | 3 |
| 37 | Department of Aviation Midway AirportGov | $65,667,192 | 944 | 1 |
| 38 | Sumit Construction Co., Inc. | $63,194,309 | 118 | 3 |
| 39 | Met Life | $62,162,308 | 205 | 2 |
| 40 | Municipal Employ Credit Union | $61,529,525 | 96 | 1 |
| 41 | K.l.e.o. Community Family Life Center | $59,462,741 | 140 | 3 |
| 42 | Aor Transit | $56,302,243 | 37 | 1 |
| 43 | Sdi Presence LLC | $55,494,288 | 288 | 2 |
| 44 | Chicago Park District | $54,662,817 | 80 | 4 |
| 45 | Reliable Contracting & Equipment Company | $49,375,279 | 58 | 2 |
| 46 | Skidmore,owings & Merrill LLP | $48,307,046 | 66 | 2 |
| 47 | Allied Waste Transportation Inc | $46,990,432 | 114 | 2 |
| 48 | City of Chicago Dept of WaterGov | $46,414,975 | 356 | 1 |
| 49 | Standard Parking Corporation 01 | $46,174,233 | 78 | 3 |
| 50 | Comed Exelon Energy Delivery | $45,956,201 | 125 | 1 |