<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><Version>2.2.0.25</Version><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><ReportLongName>0216 - Disclosure - Stock-Related Matters</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelColumn>false</LabelColumn><CurrencyCode>USD</CurrencyCode><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName>1/1/2010 - 12/31/2010
USD ($)

USD ($) / shares
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   &lt;!-- Begin Block Tagged Note 16 - us-gaap:RestrictionsOnDividendsLoansAndAdvancesTextBlock--&gt;
   &lt;div style="margin-left: 0%"&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent; text-align: left"&gt;
   &lt;tr&gt;
       &lt;td width="3%"&gt;&lt;/td&gt;
       &lt;td width="97%"&gt;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top"&gt;
       &lt;td&gt;
       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;16.&amp;#160;&lt;/font&gt;&lt;/b&gt;
   &lt;/td&gt;
       &lt;td&gt;
       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Stock-Related
       Matters&lt;/font&gt;&lt;/b&gt;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;div style="font-size: 1pt; margin-left: 0%; width: 100%;  align: left; border-bottom: 1pt solid #000000"&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 12pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent"&gt;
       &lt;b&gt;&lt;i&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Charter
       Amendment&lt;/font&gt;&lt;/i&gt;&lt;/b&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 0%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       On June&amp;#160;12, 2009, following approval by stockholders, the
       Company&amp;#8217;s Charter was amended to increase the number of
       authorized shares of capital stock from 110,000,000&amp;#160;shares
       to 275,000,000&amp;#160;shares and authorized shares of Common stock
       from 108,910,000&amp;#160;shares to 273,910,000&amp;#160;shares.
   &lt;/div&gt;
   &lt;div style="margin-top: 12pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent"&gt;
       &lt;b&gt;&lt;i&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Rights
       Agreement&lt;/font&gt;&lt;/i&gt;&lt;/b&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 0%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       The Company entered into a Rights Agreement, dated as of
       January&amp;#160;28, 2005, with the Bank of New York, which entitled
       stockholders to acquire shares of Common stock at a price equal
       to 50% of the then-current market value in limited circumstances
       when a third party acquires beneficial ownership of 15% or more
       of outstanding Common stock or commences a tender offer for at
       least 15% of Common stock, in each case, in a transaction that
       the Board of Directors does not approve. The Company entered
       into an amendment of this Rights Agreement on May&amp;#160;28, 2010
       that accelerated the expiration of the Rights Agreement.
       Following the amendment, the Rights Agreement terminated on
       May&amp;#160;28, 2010.
   &lt;/div&gt;
   &lt;div style="margin-top: 12pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent"&gt;
       &lt;b&gt;&lt;i&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Restrictions
       on Paying Dividends&lt;/font&gt;&lt;/i&gt;&lt;/b&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 0%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       Many subsidiaries (including certain consolidated partnerships,
       trusts and other non-corporate entities) are subject to
       restrictions on their ability to pay dividends or otherwise
       transfer funds to other consolidated subsidiaries and,
       ultimately, to PHH Corporation (the parent company). These
       restrictions relate to loan agreements applicable to certain
       asset-backed debt arrangements and to regulatory restrictions
       applicable to the equity of the Company&amp;#8217;s reinsurance
       subsidiary. The aggregate restricted net assets of these
       subsidiaries totaled $1.1&amp;#160;billion as of December&amp;#160;31,
       2010. These restrictions on net assets of certain subsidiaries,
       however, do not directly limit the ability to pay dividends from
       consolidated Retained earnings.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 0%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       Certain debt arrangements require the maintenance of ratios and
       contain restrictive covenants applicable to consolidated
       financial statement elements that potentially could limit the
       ability to pay dividends. Requirements of debt arrangements that
       could limit the ability to pay dividends include, but are not
       limited to:
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="text-align: left"&gt;
   &lt;tr&gt;
       &lt;td width="3%"&gt;&lt;/td&gt;
       &lt;td width="97%"&gt;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;    Pursuant to the Amended Credit Facility, the Company may not
       declare or pay any dividend, other than dividends payable solely
       in common stock, without the written consent of the lenders
       representing more than 50% of the aggregate commitments in
       effect at such time. Provided that we are not in default under
       the Amended Credit Facility, we may declare or pay a dividend so
       long as the Convertible Notes due 2012 have been repaid,
       prefunded, extended or refinanced and after giving effect to
       such dividend: (i)&amp;#160;the aggregate unrestricted Cash and cash
       equivalents is at least $50&amp;#160;million; and (ii)&amp;#160;no
       amounts are borrowed under the Amended credit facility and no
       more than $50&amp;#160;million of letters of credit are outstanding.
       Such restrictions will be suspended so long as the
       Company&amp;#8217;s corporate ratings are equal to or better than at
       least two of the following: Baa3 from Moody&amp;#8217;s Investors
       Service, BBB- from Standard&amp;#160;&amp;#038; Poor&amp;#8217;s and BBB-
       from Fitch Ratings (in each case on stable outlook or better).
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="line-height: 6pt; font-size: 1pt"&gt;
   &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;    Pursuant to the Senior Note indenture, the Company is restricted
       from paying dividends if, after giving effect to the dividend
       payment, the debt to tangible equity ratio exceeds 6:1 on the
       last day of each month.
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="line-height: 6pt; font-size: 1pt"&gt;
   &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;    Pursuant to the Medium-term note indenture, the Company is
       restricted from paying dividends if, after giving effect to the
       dividend payment, the debt to equity ratio exceeds 6.5:1.
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;/div&gt;
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   &lt;b&gt;
   &lt;font style="font-family: 'Times New Roman', Times"&gt;
   &lt;/font&gt;
   &lt;/b&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 18pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;/div&gt;
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 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 08
 -Paragraph e
 -Article 4

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