Spreadsheet: 3afae9d6-c52e-4cc6-aa69-8b3675832717
Sheet: Primary Layout

ID: | 100039495 |  |  |  |  |  |  |  | Notes/Supplemental Information:
REIT Name: | CoreSite Realty Corporation
Tax Year: | 2012
Report Date (mm/dd/yyyy): | 2013-01-23 00:00:00 |  | TARGET DELIVERY DATE: JANUARY 18, 2013
This spreadsheet and the accompanying instructions do not constitute, and should not be considered a substitute for, legal advice.  The rules governing the proper tax characterization of distributions by REITs can be complex.  Each REIT should consult its own tax advisor regarding the proper tax characterization and reporting of the REIT's distributions.
Please list Securities in [NAME]
1 | 2 | 3 | 4 |  |  |  |  |  |  |  |  |  | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 |  |  |  |  |  |  |  |  |  |  | 32
 |  |  |  |  |  |  |  |  | Total | Year Included in Shareholders' Income |  |  |  | Form 1099 Box 1a Breakdown |  | Box 1a Total |  | Form 1099 Box 1b Breakdown |  | Box 1b Total | Box 2a | Box 2b | Box 2c | Box 2d | Box 3 | Box 6 | Box 8 | Box 9 |  |  | CUSIP
 |  |  |  |  |  |  |  |  | Distribution | 2011 | 2013 | 2012 |  |  | Foreign | Ordinary | Qualified | Qualified | Qualified | Qualified | Total Capital | Unrecap |  |  |  | Foreign | Cash | Noncash | Exempt | Percentage | Number
Security |  | Ticker | Estimated | Reclass | Corrected | Record | Ex-Dividend | Payable | Per Share | (Prior Year) | (Next Year) | (Current Year) | Income | Short-term | Tax | Dividends | Income | Short-term | Foreign Tax | Dividends | [NAME]. | Sec. 1250 | Section 1202 | Collectibles | Nondividend | Tax | Liquidation | Liquidation | Interest | of AMT | Change
Description | CUSIP | Symbol | (E) | (R) | (C) | Date | Date | Date | (11+12+13) |  |  | (14+15+22+26+28) | Dividends | Capital Gain | Paid | (14+15+16) | Dividends | Gains | Paid | (18+19+20) |  | Gain | Gain | (28%) Gain | Distributions | Paid | Distr | Distr | Dividends | in Column 30 | (M) or (Y)
CoreSite Realty Corporation Common | 21870Q105 | COR |  |  |  | 2012-03-30 00:00:00 | 2012-03-28 00:00:00 | 2012-04-16 00:00:00 | 0.18 | 0 | 0 |  | 0.18 | 0 |  |  | 0 |  |  | 0 | 0 | 0 |  | 0 | 0 |  | 0 | 0
CoreSite Realty Corporation Common | 21870Q105 | COR |  |  |  | 2012-06-29 00:00:00 | 2012-06-27 00:00:00 | 2012-07-16 00:00:00 | 0.18 | 0 | 0 |  | 0.18 | 0 |  |  | 0 |  |  | 0 | 0 | 0 |  | 0 | 0 |  | 0 | 0
CoreSite Realty Corporation Common | 21870Q105 | COR |  |  |  | 2012-09-28 00:00:00 | 2012-09-26 00:00:00 | 2012-10-15 00:00:00 | 0.18 | 0 | 0 |  | 0.18 | 0 |  |  | 0 |  |  | 0 | 0 | 0 |  | 0 | 0 |  | 0 | 0
CoreSite Realty Corporation Common | 21870Q105 | COR |  |  |  | 2012-12-31 00:00:00 | 2012-12-27 00:00:00 | 2013-01-15 00:00:00 | 0.27 | 0 | 0 |  | 0.27 | 0 |  |  | 0 |  |  | 0 | 0 | 0 |  | 0 | 0 |  | 0 | 0
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CoreSite Realty Corporation Series A Preferred | 21870Q204 | COR-PA
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