<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>115 - Disclosure - Stockholders' Equity</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><CurrencyCode /><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName /><CurrencySymbol /><contextRef><ContextID>P01_01_2013To06_30_2013</ContextID><EntitySchema>http://www.sec.gov/CIK</EntitySchema><EntityValue>0001133818</EntityValue><PeriodDisplayName /><PeriodType>duration</PeriodType><PeriodStartDate>2013-01-01T00:00:00</PeriodStartDate><PeriodEndDate>2013-06-30T00:00:00</PeriodEndDate><Segments /><Scenarios /></contextRef><UPS /><CurrencyCode /><OriginalCurrencyCode /></MCU><CurrencySymbol /><Labels><Label Key="CalendarSupplement" Id="0" Label="6 Months Ended" /><Label Key="Calendar" Id="1" Label="Jun. 30, 2013" /></Labels></Column></Columns><Rows><Row FlagID="0"><Id>1</Id><IsAbstractGroupTitle>true</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>1</Level><ElementName>us-gaap_StockholdersEquityNoteAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Stockholders' Equity Note [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_StockholdersEquityNoteDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="P01_01_2013To06_30_2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>              &lt;table border="0" style="clear:both;width:100%; table-layout:fixed;"&gt;  &lt;tr&gt;  &lt;td&gt;&lt;/td&gt;  &lt;/tr&gt;  &lt;/table&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif "&gt;  &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt"&gt;  &lt;table style="clear:both;MARGIN-TOP: 0pt; FONT: 10pt Times New Roman, Times, Serif; MARGIN-BOTTOM: 0pt"   cellspacing="0" cellpadding="0" width="100%"&gt;  &lt;tr style="VERTICAL-ALIGN: top"&gt;  &lt;td style="WIDTH: 0.25in"&gt;  &lt;div&gt;&lt;strong&gt;8.&lt;/strong&gt;&lt;/div&gt;  &lt;/td&gt;  &lt;td style="TEXT-ALIGN: justify"&gt;  &lt;div&gt;&lt;strong&gt;Stockholders&amp;#8217; Equity&lt;/strong&gt;&lt;/div&gt;  &lt;/td&gt;  &lt;/tr&gt;  &lt;/table&gt;  &lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; TEXT-INDENT: -0.25in; MARGIN: 0pt 0px 0pt 0.25in; FONT: 10pt Times New Roman, Times, Serif"&gt;  &lt;strong&gt;&lt;em&gt;&amp;#160;&lt;/em&gt;&lt;/strong&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &lt;strong&gt;&lt;em&gt;Issuance of Common Stock&lt;/em&gt;&lt;/strong&gt; &amp;#150; In May  and June of 2007, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;&lt;font style=" FONT-SIZE: 10pt"&gt;  6,505,994&lt;/font&gt;&lt;/font&gt; shares of common stock for $&lt;font style=" FONT-SIZE: 10pt"&gt;6,506&lt;/font&gt; in cash to founders of the Company.  In August of 2007, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;3,975,000&lt;/font&gt; shares of common stock for  $&lt;font style=" FONT-SIZE: 10pt"&gt;993,750&lt;/font&gt; in cash to investors  in the Company pursuant to a private placement memorandum. In  August of 2007 the Company issued an additional &lt;font style=" FONT-SIZE: 10pt"&gt;1,333,334&lt;/font&gt; shares of common stock for  $&lt;font style=" FONT-SIZE: 10pt"&gt;1,000,000&lt;/font&gt; in cash to  investors in the Company pursuant to a second round of financing.  The Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;530,833&lt;/font&gt; in  common stock to the Placement Agent as commission for the shares of  common stock sold to investors. In November of 2007, the Company  issued &lt;font style=" FONT-SIZE: 10pt"&gt;3,138,889&lt;/font&gt; shares in  common stock to MD Anderson as partial consideration for its two  technology licenses from MD Anderson.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In February of 2008, the Company completed a reverse merger with  Ogden Golf Co. Corporation and issued &lt;font style=" FONT-SIZE: 10pt"&gt;38,023,578&lt;/font&gt; shares of common stock of the  public company Bio-Path Holdings (formerly Ogden Golf Co.  Corporation) in exchange for pre-merger common stock of Bio-Path,  Inc. In addition, shareholders of Ogden Golf Co. Corporation  retained &lt;font style=" FONT-SIZE: 10pt"&gt;3,600,000&lt;/font&gt; shares of  common stock of Bio-Path Holdings. In February of 2008 Bio-Path  issued &lt;font style=" FONT-SIZE: 10pt"&gt;80,000&lt;/font&gt; shares of  common stock to strategic consultants pursuant to executed  agreements and the fair value was expensed upfront as common stock  for services. In April of 2008, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;200,000&lt;/font&gt; shares of common stock to a firm  in connection with introducing Bio-Path, Inc. to its merger partner  Ogden Golf Co. Corporation. The fair value of this stock issuance  was expensed upfront as common stock for services valued at $&lt;font  style=" FONT-SIZE: 10pt"&gt;180,000&lt;/font&gt;. In April of 2008, the  Company recorded an additional &lt;font style=" FONT-SIZE: 10pt"&gt;  24&lt;/font&gt; shares for rounding in accordance with FINRA rules. In  December of 2008, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;100,000&lt;/font&gt; shares of common stock to an  investor relations firm for services. The fair value of this stock  issuance was expensed upfront as common stock for services valued  at $&lt;font style=" FONT-SIZE: 10pt"&gt;40,000&lt;/font&gt;. There were no  issuances of shares during the first quarter of 2009. In June of  2009, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;  660,000&lt;/font&gt; shares of common stock and warrants to purchase an  additional &lt;font style=" FONT-SIZE: 10pt"&gt;660,000&lt;/font&gt; shares of  common stock for $&lt;font style=" FONT-SIZE: 10pt"&gt;165,000&lt;/font&gt; in  cash to investors in the Company pursuant to a private placement  memorandum. The warrants must be exercised within two years from  the date of issuance. The exercise price of the warrants is $&lt;font  style=" FONT-SIZE: 10pt"&gt;1.50&lt;/font&gt; a share. In connection with  this private placement, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;66,000&lt;/font&gt; shares of common stock to the  Placement Agent as commission for the shares of common stock sold  to investors. There were no issuances of shares during the fourth  quarter of 2009.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In November and December of 2009, the Company sold shares of common  stock and warrants to purchase shares of common stock for $&lt;font  style=" FONT-SIZE: 10pt"&gt;&lt;font style=" FONT-SIZE: 10pt"&gt;675,000&lt;/font&gt;&lt;/font&gt; in cash to investors  pursuant to a private placement memorandum. These shares were not  issued by the December 31, 2009 year end. In January 2010, the  Company issued these investors &lt;font style=" FONT-SIZE: 10pt"&gt;  2,700,000&lt;/font&gt; shares of common stock and warrants to purchase an  additional &lt;font style=" FONT-SIZE: 10pt"&gt;2,700,000&lt;/font&gt; shares  of common stock. The warrants must be exercised within two years  from the date of issuance. The exercise price of the warrants is  $&lt;font style=" FONT-SIZE: 10pt"&gt;1.50&lt;/font&gt; a share. In January  2010, the Company also sold an additional &lt;font style=" FONT-SIZE: 10pt"&gt;900,000&lt;/font&gt; shares of common stock and  warrants to purchase an additional &lt;font style=" FONT-SIZE: 10pt"&gt;  900,000&lt;/font&gt; shares of common stock for $&lt;font style=" FONT-SIZE: 10pt"&gt;225,000&lt;/font&gt; in cash to investors in the  Company pursuant to a private placement memorandum. The warrants  must be exercised within two years from the date of issuance and  the exercise price is $&lt;font style=" FONT-SIZE: 10pt"&gt;1.50&lt;/font&gt; a  share. In connection with these private placement sales of equity,  the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;360,000&lt;/font&gt;  shares of common stock to the Placement Agent as commission for the  shares of common stock sold to investors.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In May of 2010, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;  780,000&lt;/font&gt; shares of common stock and warrants to purchase an  additional &lt;font style=" FONT-SIZE: 10pt"&gt;780,000&lt;/font&gt; shares of  common stock for $&lt;font style=" FONT-SIZE: 10pt"&gt;273,000&lt;/font&gt; in  cash to investors in the Company pursuant to a private placement  memorandum. The warrants must be exercised within two years from  the date of issuance. The exercise price of the warrants is $&lt;font  style=" FONT-SIZE: 10pt"&gt;1.50&lt;/font&gt; a share. In connection with  this private placement, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;78,000&lt;/font&gt; shares of common stock to the  Placement Agent as commission for the shares of common stock sold  to investors.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In June of 2010, the Company signed an equity purchase agreement  for up to $7 million with Lincoln Park Capital Fund, LLC  (&amp;#8220;LPC&amp;#8221; or &amp;#8220;Lincoln&amp;#8221;), a Chicago-based  institutional investor. Under the terms of the equity purchase  agreement, the Company has the right to sell shares of its common  stock to LPC from time to time over a &lt;font style=" FONT-SIZE: 10pt"&gt;24&lt;/font&gt;-month period in amounts between $&lt;font  style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; and $&lt;font style=" FONT-SIZE: 10pt"&gt;1,000,000&lt;/font&gt; up to an aggregate amount of $7  million depending upon certain conditions set forth in the purchase  agreement including that a registration statement related to the  transaction has been declared effective by the U.S. Securities and  Exchange Commission (&amp;#8220;SEC&amp;#8221;). As a result, a  registration statement was filed and later declared effective by  the SEC on July 12, 2010. Upon signing the agreement, the Company  received $&lt;font style=" FONT-SIZE: 10pt"&gt;200,000&lt;/font&gt; from LPC as  an initial purchase in exchange for &lt;font style=" FONT-SIZE: 10pt"&gt;  571,429&lt;/font&gt; shares (&amp;#8220;Initial Purchase Shares&amp;#8221;) of  the Company&amp;#8217;s common stock and warrants to purchase &lt;font  style=" FONT-SIZE: 10pt"&gt;571,429&lt;/font&gt; shares of the  Company&amp;#8217;s common stock at an exercise price of $&lt;font style=" FONT-SIZE: 10pt"&gt;1.50&lt;/font&gt; per share. Subsequent purchases of  the Company&amp;#8217;s common stock by Lincoln Park under the  agreement do not include warrants. In connection with the signing  of the LPC financing agreement, the Company issued LPC &lt;font style=" FONT-SIZE: 10pt"&gt;12,000&lt;/font&gt; shares of the Company&amp;#8217;s  common stock for its due diligence efforts and &lt;font style=" FONT-SIZE: 10pt"&gt;566,801&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee for the balance of the $7 million  equity purchase commitment.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In July of 2010, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;&lt;font style=" FONT-SIZE: 10pt"&gt;150,000&lt;/font&gt;&lt;/font&gt; from LPC in exchange for  &lt;font style=" FONT-SIZE: 10pt"&gt;375,000&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;6,251&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the &lt;font style=" FONT-SIZE: 10pt"&gt;375,000&lt;/font&gt; shares of common  stock. No warrants to purchase additional shares of common stock of  the Company were issued to Lincoln in connection with the sale of  the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In September of 2010, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; from LPC in exchange for &lt;font  style=" FONT-SIZE: 10pt"&gt;125,000&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;2,084&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 125,000 shares of common stock. No warrants to purchase  additional shares of common stock of the Company were issued to  Lincoln in connection with the sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In October of 2010, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; from LPC in exchange for &lt;font  style=" FONT-SIZE: 10pt"&gt;135,135&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;2,084&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 135,135 shares of common stock. No warrants to purchase  additional shares of common stock of the Company were issued to  Lincoln in connection with the sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In November of 2010, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; from LPC in exchange for &lt;font  style=" FONT-SIZE: 10pt"&gt;135,135&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;2,084&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 135,135 shares of common stock. No warrants to purchase  additional shares of common stock of the Company were issued to  Lincoln in connection with the sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  From November 2010 through April of 2011 the Company sold shares of  common stock for $&lt;font style=" FONT-SIZE: 10pt"&gt;1,794,205&lt;/font&gt;  in cash to investors pursuant to a private placement memorandum. In  June of 2011, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;  5,980,685&lt;/font&gt; shares of common stock to these investors. In  connection with this private placement, in June of 2011 the Company  issued &lt;font style=" FONT-SIZE: 10pt"&gt;598,069&lt;/font&gt; shares of  common stock to the Placement Agent as commission for the shares of  common stock sold to investors. No warrants to purchase additional  shares of common stock of the Company were issued to these  investors in connection with the sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In June of 2011, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; from LPC in exchange for &lt;font  style=" FONT-SIZE: 10pt"&gt;164,853&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;2,084&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 164,853 shares of common stock. No warrants to purchase  additional shares of common stock of the Company were issued to  Lincoln in connection with the sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In October of 2011, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;1,920,000&lt;/font&gt; shares of common stock for  $&lt;font style=" FONT-SIZE: 10pt"&gt;576,000&lt;/font&gt; to investors who  exercised warrants from September to October 2011.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In November of 2011, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;25,000&lt;/font&gt; from LPC in exchange for 83,333  shares of the Company&amp;#8217;s common stock. LPC was also issued  1,042 shares of the Company&amp;#8217;s common stock as a commitment  fee in connection with the purchase of the 83,333 shares of common  stock. No warrants to purchase additional shares of common stock of  the Company were issued to Lincoln in connection with the sale of  the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In December of 2011, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; from LPC in exchange for &lt;font  style=" FONT-SIZE: 10pt"&gt;172,414&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;2,084&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 172,414 shares of common stock. No warrants to purchase  additional shares of common stock of the Company were issued to  Lincoln in connection with the sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In March of 2012, the Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; from LPC in exchange for &lt;font  style=" FONT-SIZE: 10pt"&gt;166,667&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;2,084&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 166,667 shares of common stock. No warrants to purchase  additional shares of common stock of the Company were issued to  Lincoln in connection with the sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In April of 2012, LPC made three separate purchases of the  Company&amp;#8217;s common stock. The Company received $&lt;font style=" FONT-SIZE: 10pt"&gt;25,000&lt;/font&gt; from LPC in exchange for &lt;font  style=" FONT-SIZE: 10pt"&gt;89,286&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;1,042&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 89,286 shares of common stock. The Company received another  $&lt;font style=" FONT-SIZE: 10pt"&gt;25,000&lt;/font&gt; from LPC in exchange  for &lt;font style=" FONT-SIZE: 10pt"&gt;96,154&lt;/font&gt; shares of the  Company&amp;#8217;s common stock. LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;1,042&lt;/font&gt; shares of the Company&amp;#8217;s  common stock as a commitment fee in connection with the purchase of  the 96,154 shares of common stock. Finally, the Company received  $&lt;font style=" FONT-SIZE: 10pt"&gt;&lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt;&lt;/font&gt; from LPC in exchange for  &lt;font style=" FONT-SIZE: 10pt"&gt;&lt;font style=" FONT-SIZE: 10pt"&gt;  185,185&lt;/font&gt;&lt;/font&gt; shares of the Company&amp;#8217;s common stock.  LPC was also issued &lt;font style=" FONT-SIZE: 10pt"&gt;&lt;font style=" FONT-SIZE: 10pt"&gt;2,084&lt;/font&gt;&lt;/font&gt; shares of the  Company&amp;#8217;s common stock as a commitment fee in connection with  the purchase of the 185,185 shares of common stock. No warrants to  purchase additional shares of common stock of the Company were  issued to Lincoln in connection with the sale of the common  stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In June of 2012, the Company sold $&lt;font style=" FONT-SIZE: 10pt"&gt;150,000&lt;/font&gt; in shares of its common stock  pursuant to a private placement, with shares to be issued, and  $&lt;font style=" FONT-SIZE: 10pt"&gt;18,500&lt;/font&gt; in shares of its  common stock for services with shares to be issued.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In August of 2012, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;50,000&lt;/font&gt; shares of its common stock for the  $&lt;font style=" FONT-SIZE: 10pt"&gt;18,500&lt;/font&gt; shares for services  previously recognized in June 2012.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In July through September of 2012, the Company sold $&lt;font style=" FONT-SIZE: 10pt"&gt;795,001&lt;/font&gt; in shares of its common stock  pursuant to a private placement, with shares to be issued.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In October through December of 2012, the Company sold $&lt;font style=" FONT-SIZE: 10pt"&gt;708,600&lt;/font&gt; in shares of its common stock  pursuant to a private placement, with shares to be issued.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  As of December 31, 2012 the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;3,300,337&lt;/font&gt; shares of its common stock to  investors who purchased shares of common stock from the period June  through September of 2012.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In February and March of 2013, the Company sold $&lt;font style=" FONT-SIZE: 10pt"&gt;346,201&lt;/font&gt; in shares of its common stock  pursuant to a private placement, with shares to be issued.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In April and May of 2013, the Company sold $&lt;font style=" FONT-SIZE: 10pt"&gt;2,000,198&lt;/font&gt; in shares of its common stock  pursuant to a private placement, with shares to be issued, and  $&lt;font style=" FONT-SIZE: 10pt"&gt;489,501&lt;/font&gt; in shares of its  common stock pursuant in a direct offering, with shares to be  issued.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  In June of 2013, the Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;  11,664,665&lt;/font&gt; shares of common stock to investors in connection  with the private placement and direct offering. In June of 2013 the  Company issued &lt;font style=" FONT-SIZE: 10pt"&gt;1,496,499&lt;/font&gt;  shares of common stock to the Placement Agent as commission for the  shares of common stock sold to investors. No warrants to purchase  additional shares of common stock of the Company were issued to  these investors or to the Placement Agent in connection with the  sale of the common stock.&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  As of June 30, 2013, there were &lt;font style=" FONT-SIZE: 10pt"&gt;  &lt;font style=" FONT-SIZE: 10pt"&gt;75,380,214&lt;/font&gt;&lt;/font&gt; shares of  common stock issued and outstanding. There are no preferred shares  outstanding as of June 30, 2013.&lt;/div&gt;  &lt;/div&gt;        </NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 210

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.5-02.29-31)

 -URI http://asc.fasb.org/extlink&amp;oid=6877327&amp;loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 6

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21506-112644



Reference 3: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 02

 -Paragraph 29, 30, 31

 -Article 5



Reference 4: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 310

 -SubTopic 10

 -Section S99

 -Paragraph 2

 -Subparagraph (SAB TOPIC 4.E)

 -URI http://asc.fasb.org/extlink&amp;oid=27010918&amp;loc=d3e74512-122707



Reference 5: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section S99

 -Paragraph 4

 -Subparagraph (SAB TOPIC 4.C)

 -URI http://asc.fasb.org/extlink&amp;oid=27012166&amp;loc=d3e187143-122770



Reference 6: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 08

 -Article 4



Reference 7: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Staff Accounting Bulletin (SAB)

 -Number Topic 4

 -Section C



Reference 8: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Staff Accounting Bulletin (SAB)

 -Number Topic 4

 -Section E



Reference 9: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 235

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.4-08.(d),(e))

 -URI http://asc.fasb.org/extlink&amp;oid=26873400&amp;loc=d3e23780-122690



Reference 10: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Glossary Preferred Stock

 -URI http://asc.fasb.org/extlink&amp;oid=6521494



Reference 11: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 04

 -Article 3



Reference 12: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 2

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21463-112644



Reference 13: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.3-04)

 -URI http://asc.fasb.org/extlink&amp;oid=27012166&amp;loc=d3e187085-122770



Reference 14: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 3

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21475-112644



Reference 15: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 11

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21564-112644



Reference 16: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 5

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21488-112644



Reference 17: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 4

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21484-112644



Reference 18: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 08

 -Paragraph d

 -Article 4



Reference 19: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 30

 -Section 50

 -Paragraph 2

 -URI http://asc.fasb.org/extlink&amp;oid=6405834&amp;loc=d3e23285-112656



</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Stockholders' Equity</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Stockholders' Equity</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.biopathholdings.com/role/StockholdersEquity</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
