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style="font-family:'Segoe UI Symbol';">&#9744;</span></ix:nonNumeric>&#160;&#160;&#160;&#160;&#160;&#160;Pre-commencement communications pursuant to Rule&#160;13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt 0pt 1.5pt 0pt;">Securities registered pursuant to Section 12(b) of the Act:</p><a id="_7b04039a_68eb_4a1c_b4ad_33c98e438a69"></a><a id="Tc_pMi9kexDbEiLIF-v-kyEEQ_1_0"></a><a id="Tc_7CtuEzgFCEu1Dn422QBvtA_1_1"></a><a id="Tc_DGLOfiAOKEaw5hqixFKFeg_1_2"></a><table style="border-collapse:collapse;font-size:16pt;width:99.89%;"><tr style="height:1pt;"><td style="vertical-align:top;width:38.05%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span 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style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><b style="font-weight:bold;text-decoration:underline;text-decoration-color:#000000;">Title of Each Class</b></p></td><td style="vertical-align:top;width:18.56%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><b style="font-weight:bold;text-decoration:underline;text-decoration-color:#000000;">Trading Symbol</b></p></td><td style="vertical-align:top;width:43.37%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><b style="font-weight:bold;text-decoration:underline;text-decoration-color:#000000;">Name of each exchange on which registered</b></p></td></tr><tr><td style="vertical-align:top;width:38.05%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_7_30_2020_To_7_30_2020_IGa5Y8inaUittQkjS36ZyQ" name="dei:Security12bTitle" id="Tc_8LYrmcGq50eR2ZjmtDVvUA_2_0">Common Stock, $0.01 par value per share</ix:nonNumeric></p></td><td style="vertical-align:top;width:18.56%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_7_30_2020_To_7_30_2020_IGa5Y8inaUittQkjS36ZyQ" name="dei:TradingSymbol" id="Tc_Ycim_yCy4EyJGI2pPfmKEQ_2_1">COR</ix:nonNumeric></p></td><td style="vertical-align:top;width:43.37%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_7_30_2020_To_7_30_2020_IGa5Y8inaUittQkjS36ZyQ" format="ixt-sec:exchnameen" name="dei:SecurityExchangeName" id="Tc_Ukz2Q3CqZUOjql0tgC4qdA_2_2">New York Stock Exchange</ix:nonNumeric></p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-size:8pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-size:8pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Emerging growth company <ix:nonNumeric contextRef="Duration_7_30_2020_To_7_30_2020_IGa5Y8inaUittQkjS36ZyQ" format="ixt-sec:boolballotbox" name="dei:EntityEmergingGrowthCompany" id="Narr_I8vxyliFq02UcNteynz0rg"><span style="font-family:'Segoe UI Symbol';">&#9744;</span></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-family:'Wingdings';font-size:8pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. <span style="font-family:'Segoe UI Symbol';">&#9744;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><span style="font-size:6pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1pt;padding-bottom:1pt;padding-top:1pt;text-align:center;border-bottom:3.0pt solid #000000;border-top:1.0pt solid #000000;margin:0pt;"><span style="font-size:1pt;line-height:1.19;visibility:hidden;">&#8203;</span></p><p style="display:none;font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:0pt;margin:0pt;"><span style="font-size:0pt;line-height:1.19;visibility:hidden;">&#8203;</span></p><a id="_dcb15f62_476d_48bd_b93d_e3b5ed98e0bb"></a></div><div style="clear:both;margin-bottom:27.35pt;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><b style="font-weight:bold;">Section&#160;2 &#8212; Financial Information</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">Item&#160;2.02 Results of Operations and Financial Condition.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">On July 30, 2020, CoreSite Realty Corporation (&quot;CoreSite&quot;) issued a press release reporting financial results and operating information for the quarter ended June 30, 2020. In addition, CoreSite made available on its website supplemental operating and financial data for the same period. The text of the press release and the supplemental information package are furnished herewith as Exhibits 99.1 and 99.2, respectively.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">The information in this report, including Exhibits 99.1 and 99.2 attached hereto, shall not be deemed to be &quot;filed&quot; for purposes of Section&#160;18 of the Securities Exchange Act of 1934, as amended (the &quot;Exchange Act&quot;), or otherwise subject to the liabilities of that section, and shall not be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><b style="font-weight:bold;">Section&#160;9 &#8212; Financial Statements and Exhibits</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">Item&#160;9.01 Financial Statements and Exhibits.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">(d)&#160;The following exhibits are furnished with this Current Report on Form 8-K.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><table style="border-collapse:collapse;font-size:16pt;margin-left:auto;margin-right:auto;padding-left:0pt;padding-right:0pt;width:100%;"><tr><td style="vertical-align:top;width:8.33%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">Exhibit&#160;No.</b></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;line-height:1.19;margin:0pt;">&#160;&#160;&#160;&#160;</p></td><td style="vertical-align:top;width:89.26%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">Description</b></p></td></tr><tr><td style="vertical-align:top;width:8.33%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">99.1</p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><a href="cor-20200730ex99106795a.htm"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;line-height:1.19;text-align:left;">Press Release, dated July 30, 2020.</span></a></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">99.2</p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><a href="cor-20200730ex992942b3d.htm"><span style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:normal;font-weight:normal;line-height:1.19;text-align:left;">Quarter Ended June 30, 2020, Earnings Release and Supplemental Information, dated July 30, 2020.</span></a></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">101.INS</p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">XBRL Instance &#8211; the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.</p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">101.SCH</p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">XBRL Taxonomy Extension Schema Document.</p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">101.LAB</p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">XBRL Taxonomy Extension Labels Linkbase Document.</p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">101.PRE</p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">XBRL Taxonomy Extension Presentation Linkbase Document.</p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:8.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">104</p></td><td style="vertical-align:top;width:2.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:89.26%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101).</p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p><a id="_46b086b6_ca62_47b3_908c_bc40bd8c749d"></a></div><div style="clear:both;display:table;margin-bottom:27.35pt;min-height:36pt;width:100%;"><div style="display:table-cell;vertical-align:bottom;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:24pt 0pt 0pt 0pt;">2</p></div></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><a id="_313671"></a><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><b style="font-weight:bold;">SIGNATURES</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><table style="border-collapse:collapse;font-size:16pt;margin-left:auto;margin-right:auto;padding-left:0pt;padding-right:0pt;width:100%;"><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td colspan="2" style="vertical-align:top;width:49.27%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">CORESITE REALTY CORPORATION</b></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-weight:bold;visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Date: July 30, 2020</p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">By:</p></td><td style="vertical-align:top;width:46.21%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">/s/ Jeffrey S. Finnin</b></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Name:&#160;<b style="font-weight:bold;">Jeffrey S. Finnin</b></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Title:&#160;&#160;&#160;<b style="font-weight:bold;">Chief Financial Officer</b></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">By:</p></td><td style="vertical-align:top;width:46.21%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">/s/ Mark R. Jones</b></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><b style="font-weight:bold;">Name:&#160;Mark R. Jones</b></p></td></tr><tr><td style="vertical-align:top;width:50.72%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:3.05%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:46.21%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;">Title:&#160;&#160;&#160;<b style="font-weight:bold;">Chief Accounting Officer</b></p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="font-size:1pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.37;margin:0pt 0pt 10pt 0pt;"><span style="line-height:1.19;margin-bottom:0pt;visibility:hidden;">&#8203;</span></p></div><div style="clear:both;display:table;margin-bottom:27.35pt;min-height:36pt;width:100%;"><div style="display:table-cell;vertical-align:bottom;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;line-height:1.19;text-align:center;margin:24pt 0pt 0pt 0pt;">3</p></div></div></div>
<div style="background-color:#000000;clear:both;height:2pt;margin-left:10.35%;margin-right:10.35%;margin-top:30pt;page-break-after:avoid;width:79.3%;border:0;"></div></body></html>
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{"company-data": {"conformed-name": "CoreSite Realty Corp", "cik": "0001490892", "assigned-sic": "6798", "irs-number": "000000000", "state-of-incorporation": "MD", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-34877", "film-number": "201059269"}, "business-address": {"street1": "1001 17TH STREET", "street2": "SUITE 500", "city": "DENVER", "state": "CO", "zip": "80202", "phone": "(866) 777-2673"}, "mail-address": {"street1": "1001 17TH STREET", "street2": "SUITE 500", "city": "DENVER", "state": "CO", "zip": "80202"}}
​
​
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM
8-K
CURRENT REPORT
Pursuant to Section 13 OR 15(d) of The
Securities Exchange Act of 1934
​
Date of Report (Date of earliest event reported):
July 30, 2020
CoreSite Realty Corp
oration
(Exact name of registrant as specified in its charter)
​
Maryland
001-34877
27-1925611
(State or other jurisdiction
(Commission
(IRS Employer
of incorporation)
File Number)
Identification No.)
​
​
​
1001 17th Street, Suite 500
​
Denver
,
CO
80202
(Address of principal executive offices)
(Zip Code)
​
Registrant's telephone number, including area code: (
866
)
777-2673
​
N/A
(Former name or former address, if changed since last report.)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
​
☐
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Securities registered pursuant to Section 12(b) of the Act:
​
​
​
Title of Each Class
Trading Symbol
Name of each exchange on which registered
Common Stock, $0.01 par value per share
COR
New York Stock Exchange
​
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934.
​
Emerging growth company
☐
​
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
☐
​
​
​
Section 2 — Financial Information
​
Item 2.02 Results of Operations and Financial Condition.
​
On July 30, 2020, CoreSite Realty Corporation ("CoreSite") issued a press release reporting financial results and operating information for the quarter ended June 30, 2020. In addition, CoreSite made available on its website supplemental operating and financial data for the same period. The text of the press release and the supplemental information package are furnished herewith as Exhibits 99.1 and 99.2, respectively.
​
The information in this report, including Exhibits 99.1 and 99.2 attached hereto, shall not be deemed to be "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or otherwise subject to the liabilities of that section, and shall not be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.
​
Section 9 — Financial Statements and Exhibits
​
Item 9.01 Financial Statements and Exhibits.
​
(d) The following exhibits are furnished with this Current Report on Form 8-K.
​
Exhibit No.
Description
​
​
​
99.1
​
Press Release, dated July 30, 2020.
​
​
​
99.2
​
Quarter Ended June 30, 2020, Earnings Release and Supplemental Information, dated July 30, 2020.
​
​
​
101.INS
​
XBRL Instance – the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.
​
​
​
101.SCH
​
XBRL Taxonomy Extension Schema Document.
​
​
​
101.LAB
​
XBRL Taxonomy Extension Labels Linkbase Document.
​
​
​
101.PRE
​
XBRL Taxonomy Extension Presentation Linkbase Document.
​
​
​
104
​
Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101).
​
​
​
2
SIGNATURES
​
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
​
​
CORESITE REALTY CORPORATION
​
​
​
​
​
​
Date: July 30, 2020
By:
/s/ Jeffrey S. Finnin
​
​
Name:
Jeffrey S. Finnin
​
​
Title:
Chief Financial Officer
​
​
​
​
​
​
​
By:
/s/ Mark R. Jones
​
​
Name: Mark R. Jones
​
​
Title:
Chief Accounting Officer
​
​
​
3