The top 25 office owners survey includes office space owned globally as of Dec. 31, 2011. If companies had interests in mixed-use projects, they were asked to provide the totals for the office portion only.

1. Brookfield Office Properties
Total Office Portfolio: 82.0 million sq. ft.
PH: 212.417.7000
www.brookfieldofficeproperties.com

2. The Blackstone Group
Total Office Portfolio: 75.0 million sq. ft.
PH: 212.583.5000
www.blackstone.com

3. RREEF
Total Office Portfolio: 54.33 million sq. ft.
PH: 212.454.6260
www.rreef.com

4. Hines
Total Office Portfolio: 47.35 million sq. ft.
PH: 713.621.8000
www.hines.com

5. KBS Realty Advisors
Total Office Portfolio: 46.28 million sq. ft.
PH: 949.417.6500
www.kbsrealty.com

6. TIAA-CREF
Total Office Portfolio: 42.00 million sq. ft.
PH: 800.824.2733
www.tiaa-cref.org

7. LaSalle Investment Management
Total Office Portfolio: 41.80 million sq. ft.
PH: 312.782.5800
www.lasalle.com

8. Vornado Realty Trust
Total Office Portfolio: 40.10 million sq. ft.
PH: 212.894.7000
www.vno.com

9. CommonWealth REIT
Total Office Portfolio: 40.00 million sq. ft.
PH: 617.332.3990
www.cwhreit.com

10. Boston Properties
Total Office Portfolio: 38.22 million sq. ft.
PH: 617.236.3300
www.bostonproperties.com

11. Brandywine Realty Trust
Total Office Portfolio: 34.60 million sq. ft.
PH: 610.325.5600
www.brandywinerealty.com

12. Mack-Cali Realty Corp.
Total Office Portfolio: 32.01 million sq. ft.
PH: 732.590.1000
www.mack-cali.com

13. SL Green Realty Corp.
Total Office Portfolio: 31.43 million sq. ft.
PH: 212.594.2700
www.slgreen.com

14. Duke Realty
Total Office Portfolio: 27.70 million sq. ft.
PH: 317.808.6000
www.dukerealty.com

15. Liberty Property Trust
Total Office Portfolio: 25.03 million sq. ft.
PH: 610.648.1700
www.libertyproperty.com

16. Highwoods Properties
Total Office Portfolio: 22.61 million sq. ft.
PH: 919.872.4924
www.highwoods.com

17. Wells REIT II
Total Office Portfolio: 22.00 million sq. ft.
PH: 770.449.7800
www.wellsreitii.com

18. Piedmont Office Realty Trust
Total Office Portfolio: 20.90 million sq. ft.
PH: 770.418.8800
www.piedmontreit.com

19. Corporate Office Properties Trust
Total Office Portfolio: 20.50 million sq. ft.
PH: 443.285.5400
www.copt.com

20. Shorenstein Properties
Total Office Portfolio: 19.80 million sq. ft.
PH: 415.772.7000
www.shorenstein.com

21. AEW Capital Management L.P.
Total Office Portfolio: 17.80 million sq. ft.
PH: 617.261.9000
www.aew.com

22. Lincoln Property Co.
Total Office Portfolio: 16.46 million sq. ft.
PH: 214.474.3300
www.lincolnproperty.com

23. The Alter Group
Total Office Portfolio: 13.86 million sq. ft.
PH: 847.676.4300
www.altergroup.com

24. Kilroy Realty Corp.
Total Office Portfolio: 11.42 million sq. ft.
PH: 310.481.8400
www.kilroyrealty.com

25. The Inland Real Estate Group of Companies
Total Office Portfolio: 11.13 million sq. ft.
PH: 630.218.8000
www.inlandgroup.com