13F-NT 1 senator13f093010.txt UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 13F FORM 13F COVER PAGE Report for the Calendar Year or Quarter Ended: September 30, 2010 Check here if Amendment [ ]; Amendment Number: This amendment (Check only one.): [ ] is a restatement. [ ] adds new holdings entries. Institutional Investment Manager Filing this Report: Name: Senator Investment Group LP Address: 1330 Avenue of the Americas, 26th Floor New York, NY 10019 13 File Number: The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct, and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form Person Signing this Report on Behalf of Reporting Manager: Name: Edward Larmann Title: Chief Financial Officer Phone: (212) 376-4305 Signature, Place and Date of Signing: Edward Larmann New York, NY November XX, 2010 Report Type (Check only one.): [ X] 13F HOLDINGS REPORT. [ ] 13F NOTICE. [ ] 13F COMBINATION REPORT. FORM 13F SUMMARY PAGE Report Summary: Number of Other Included Managers: 0 Form 13F Information Table Entry Total: 46 Form 13F Information Table Value Total: $1,959,953 (thousands) List of Other Included Managers: Provide a numbered list of the name(s) and Form 13F file number(s) of all institutional managers with respect to which this report is filed, other than the manager filing this report. NONE FORM 13F INFORMATION TABLE VALUE SHARES/ SH/ PUT/ INVSTMT OTHER VOTING AUTHORITY NAME OF ISSUER TITLE OF CLASS CUSIP x($1000) PRN AMT PRN CALL DISCRETN MANAGERS SOLE SHARED NONE ------------------------------ ---------------- --------- -------- -------- --- ---- -------- --------- -------- -------- -------- Alpha Natural Resources Inc COM 02076X102 34978 850000 SOLE 8500000 0 0 Aspen Technology Inc COM 045327103 25910 2498586 SOLE 2498586 0 0 Avis Budget Group COM 053774105 64089 5501200 SOLE 5501200 0 0 Citigroup Inc COM 172967101 46920 12000000 SOLE 12000000 0 0 Cogent Inc COM 19239Y108 10640 1000000 SOLE 1000000 0 0 Celera Corp COM 15100E106 33700 5000000 SOLE 5000000 0 0 Dollar Thrifty Automotive GP CALL 256743905 50692 10110 CALL SOLE 10110 0 0 Energy XXI (Bermuda) Ltd COM G10082140 29775 1288406 SOLE 1288406 0 0 Energy XXI (Bermuda) Ltd COM G10082140 4890 211594 SOLE 211594 0 0 Forest Labs Inc COM 345838106 52581 1700000 SOLE 1700000 0 0 Graham Packaging Co Inc. COM 384701108 35885 3036026 SOLE 3036026 0 0 Harvest Natural Resources Inc COM 41754V103 7049 676500 SOLE 676500 0 0 Hertz Global Holdings Inc COM 42805T105 42360 4000000 SOLE 4000000 0 0 Huntsman Corp COM 447011107 39882 3450000 SOLE 3450000 0 0 Huntsman Corp CALL 447011907 2890 2500 CALL SOLE 2500 0 0 Idera Pharmaceuticals Inc COM 451685306 10642 3234505 SOLE 3234505 0 0 IShares Russell 2000 PUT 464287955 67500 10000 PUT SOLE 10000 0 0 IShares Russell 2000 PUT 464287955 67500 10000 PUT SOLE 10000 0 0 IShares Russell 2000 PUT 464287955 472500 70000 PUT SOLE 70000 0 0 JPMorgan chase & Co COM 46625H100 20933 550000 SOLE 550000 0 0 Lear Corp COM 521865204 33545 425000 SOLE 425000 0 0 Liberty Media Corp DEB 530715AG6 5756 10000000 SOLE 10000000 0 0 Macquarie Infrastr Co LLC COM 55608B105 55067 3552700 SOLE 3552700 0 0 Martin Marietta Matls Inc COM 573284106 12315 160000 SOLE 160000 0 0 Medtronic Inc COM 585055106 33580 1000000 SOLE 1000000 0 0 Murphy Oil Corp COM 626717102 30960 500000 SOLE 500000 0 0 Pharmerica Corp COM 71714F104 14295 1500000 SOLE 1500000 0 0 Plains Expl & Prodtn Co COM 726505100 33338 1250000 SOLE 1250000 0 0 Plains Expl & Prodtn Co CALL 726505900 66675 25000 CALL SOLE 25000 0 0 Potash Corp Sask Inc COM 73755L107 56258 390570 SOLE 390570 0 0 Savient Pharmaceuticals Inc COM 80517Q100 34305 1500000 SOLE 1500000 0 0 SAVVIS Inc COM 805423308 10540 500000 SOLE 500000 0 0 Skechers U S A Inc COM 830566105 7231 307842 SOLE 307842 0 0 Smurfit-Stone Container Corp COM 83272A104 18940 1031019 SOLE 1031019 0 0 Solutia Inc COM 834376501 18984 1185000 SOLE 1185000 0 0 St Jude Med Inc CALL 790849903 39340 10000 CALL SOLE 10000 0 0 TCF Finl Corp COM 872275102 12952 800000 SOLE 800000 0 0 Temple Inland Inc COM 879868107 74748 4005800 SOLE 4005800 0 0 Temple Inland Inc CALL 879868907 1306 700 CALL SOLE 700 0 0 Textron Inc CALL 883203901 20560 10000 CALL SOLE 10000 0 0 Time Warner Inc COM 88732J207 53990 1000000 SOLE 1000000 0 0 UAL Corp COM 910047109 62699 2650000 SOLE 2650000 0 0 Virgin Media Inc COM 92769L101 46120 2000000 SOLE 2000000 0 0 Weyerhaeuser Co COM 962166104 9700 615452 SOLE 615452 0 0 Williams Cos Inc Del COM 969457100 52553 2750000 SOLE 2750000 0 0 United States Stl Corp New COM 912909008 32880 750000 SOLE 750000 0 0