MACK CALI REALTY CORP
EXHIBIT 10.26
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<TYPE>EX-10.26
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<DESCRIPTION>EXHIBIT 10.26
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<P ALIGN="RIGHT"><FONT SIZE=2><A
NAME="ns8969_exhibit_10.26"> </A>
<A NAME="toc_ns8969_1"> </A>
<BR></FONT><FONT SIZE=2><B>Exhibit&nbsp;10.26    <BR>  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ns8969_first_amendment_to_agreement_o__fir02782"> </A>
<A NAME="toc_ns8969_2"> </A>
<BR></FONT><FONT SIZE=2><B>FIRST AMENDMENT TO<BR>  AGREEMENT OF SALE AND PURCHASE<BR>  </B></FONT><FONT SIZE=2>(Talavi Business Park)    <BR></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This
</FONT><FONT SIZE=2><B>FIRST AMENDMENT TO AGREEMENT OF SALE AND PURCHASE</B></FONT><FONT SIZE=2> (this "</FONT><FONT SIZE=2><B>Amendment</B></FONT><FONT SIZE=2>") is dated as of
August&nbsp;15, 2002, by and between </FONT><FONT SIZE=2><B>MACK-CALI GLENDALE LIMITED PARTNERSHIP,</B></FONT><FONT SIZE=2> a limited partnership organized under the laws of the State
of Arizona ("</FONT><FONT SIZE=2><B>Seller</B></FONT><FONT SIZE=2>"), having an address at c/o Mack-Cali Realty Corporation, 11&nbsp;Commerce Drive, Cranford, New Jersey 07016 and </FONT> <FONT SIZE=2><B>SUMMIT COMMERCIAL PROPERTIES,
&nbsp;INC.</B></FONT><FONT SIZE=2>, a corporation organized under the laws of the State of California
("</FONT><FONT SIZE=2><B>Purchaser</B></FONT><FONT SIZE=2>"), having an address at c/o Summit Commercial, 1970&nbsp;East Grand Avenue, Suite&nbsp;300, El&nbsp;Segundo, California 90245. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B><I>W I T N E S S E T H:</I></B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>WHEREAS</B></FONT><FONT SIZE=2>, Seller and Purchaser have entered into a certain Agreement of Sale and Purchase dated as of July&nbsp;2, 2002 (the
"</FONT><FONT SIZE=2><B>Agreement</B></FONT><FONT SIZE=2>") pursuant to which Agreement Seller agreed to sell and Purchaser agreed to purchase certain Property located at 5551&nbsp;West Talavi
Boulevard, Glendale, Arizona; and </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>WHEREAS</B></FONT><FONT SIZE=2>, Seller and Purchaser have agreed to amend the Agreement as hereinafter set forth. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>NOW, THEREFORE</B></FONT><FONT SIZE=2>, in consideration of the mutual covenants and agreements hereinafter set forth and other good and valuable consideration,
the receipt and sufficiency whereof is hereby acknowledged, intending to be legally bound hereby, the parties hereby agree as follows: </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1.&nbsp;&nbsp;&nbsp;&nbsp;The
word "Realty", which was incorrectly inserted in the Agreement as part of Seller's name, is hereby deleted and all references to Seller in the Agreement shall be
deemed to refer to "Mack-Cali Glendale Limited Partnership". </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2.&nbsp;&nbsp;&nbsp;&nbsp;The
first sentence of the defined term "Closing Date" as set forth in Section&nbsp;1.1 of the Agreement is hereby deleted in its entirety and replaced with the
following "</FONT><FONT SIZE=2><I>Closing Date</I></FONT><FONT SIZE=2>" means October&nbsp;2, 2002". The second sentence of such defined term is hereby modified to replace the phrase "sixty
(60)&nbsp;days" with the phrase "thirty (30)&nbsp;days". </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3.&nbsp;&nbsp;&nbsp;&nbsp;The
"Evaluation Period" as defined in Section&nbsp;5.1 of the Agreement is hereby extended to 5:00&nbsp;p.m. Eastern time on September&nbsp;6, 2002. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4.&nbsp;&nbsp;&nbsp;&nbsp;The
defined term "Portfolio Sale and Purchase Agreement" as set forth in Section&nbsp;1.1 of the Agreement is hereby deleted in its entirety and replaced with the
following definition: "</FONT><FONT SIZE=2><B><I>Portfolio Sale and Purchase Agreement</I></B></FONT><FONT SIZE=2>" means each of (i)&nbsp;that certain Agreement of Sale and Purchase dated as of
July&nbsp;2, 2002 by and between Mack-Cali Beardsley Limited Partnership, as seller, and Purchaser, as purchaser, as amended by that certain First Amendment to Agreement of Sale and
Purchase dated August&nbsp;15, 2002, and (ii)&nbsp;that certain Agreement of Sale and Purchase dated as of July&nbsp;2, 2002 by and between Mack-Cali Realty 9060,&nbsp;L.L.C., as
seller and Purchaser, as purchaser, as amended by that certain First Amendment to Agreement of Sale and Purchase dated August&nbsp;15, 2002, for the sale and purchase of each Portfolio Property
defined therein, as such agreements may hereinafter be amended from time to time." </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5.&nbsp;&nbsp;&nbsp;&nbsp;All
other terms, conditions and provisions of the Agreement shall continue in full force and effect and unmodified, except to the extent expressly modified hereby. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.&nbsp;&nbsp;&nbsp;&nbsp;Capitalized
terms used and not otherwise defined herein shall have the meanings respectively assigned to them in the Agreement. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.&nbsp;&nbsp;&nbsp;&nbsp;This
Amendment shall be binding upon and inure to the benefit of the successors, legal representatives, heirs and assigns of the parties hereto. </FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.&nbsp;&nbsp;&nbsp;&nbsp;This
Amendment may be executed by facsimile signatures in any number of counterparts, each of which shall be deemed an original and all of which when considered together
shall be one and the same document. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.&nbsp;&nbsp;&nbsp;&nbsp;In
the event of any conflict between the terms of this Amendment and the terms of the Agreement, the terms of this Amendment shall control. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><I>[The remainder of this page is left intentionally blank.]</I></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

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<P><FONT SIZE=2>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT SIZE=2><B>IN WITNESS WHEREOF</B></FONT><FONT SIZE=2>, the parties hereto have executed this Amendment as of the day and year first above written. </FONT></P>

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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2><B><I>SELLER:</I></B></FONT></TD>
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&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2><BR>
MACK-CALI GLENDALE LIMITED PARTNERSHIP</FONT></TD>
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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2>By:</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2>Mack-Cali Sub XXII,&nbsp;Inc. its general partner</FONT></TD>
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<TR VALIGN="TOP">
<TD WIDTH="45%"><FONT SIZE=2><BR>
<BR></FONT>
</TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
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<TD WIDTH="11%"><FONT SIZE=2>By:</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2>/s/ Roger W. Thomas</FONT><HR NOSHADE></TD>
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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2>Name:</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2>Roger W. Thomas</FONT><HR NOSHADE></TD>
</TR>
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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2>Title:</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2>Executive Vice President &amp; General Counsel</FONT><HR NOSHADE></TD>
</TR>
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<TD WIDTH="45%"><FONT SIZE=2><BR>
<BR></FONT>
</TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2><B><I>PURCHASER:</I></B></FONT></TD>
</TR>
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<TD WIDTH="45%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2><BR>
SUMMIT COMMERCIAL PROPERTIES,&nbsp;INC.</FONT></TD>
</TR>
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<TD WIDTH="45%"><FONT SIZE=2><BR>
<BR></FONT>
</TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2>By:</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2>/s/ Larry M. Matsui</FONT><HR NOSHADE></TD>
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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2>Name:</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2>Larry M. Matsui</FONT><HR NOSHADE></TD>
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<TD WIDTH="45%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="11%"><FONT SIZE=2>Title:</FONT></TD>
<TD WIDTH="41%"><FONT SIZE=2>Executive Vice President/CFO</FONT><HR NOSHADE></TD>
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<P><br><A NAME="02NYC8968_9">QuickLinks</A><br></P><!-- TOC_BEGIN -->
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<FONT SIZE=2><A HREF="#toc_ns8969_1">Exhibit 10.26</A></FONT><BR>
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<FONT SIZE=2><A HREF="#toc_ns8969_2">FIRST AMENDMENT TO AGREEMENT OF SALE AND PURCHASE (Talavi Business Park)</A></FONT><BR>

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