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  <p style="border:none;margin:0in 0in .0001pt;padding:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
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  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">SECURITIES AND EXCHANGE COMMISSION</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">WASHINGTON, D.C. 20549</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">FORM&nbsp;8-K</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">CURRENT REPORT<br>
  PURSUANT TO SECTION&nbsp;13 OR 15(D)&nbsp;OF THE<br>
  SECURITIES EXCHANGE ACT OF 1934</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Date of report (Date of earliest event reported):<b>&#160; May&nbsp;20, 2008</b></font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">ADVANCED CELL TECHNOLOGY, INC.</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Exact name of registrant as specified in its charter)</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
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    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Delaware</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">000-50295</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">87-0656515</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(State or other jurisdiction<br>
    of&nbsp;incorporation)</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Commission File Number)</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(IRS Employer Identification Number)</font></p>
    </td>
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  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">381 Plantation Street Worcester, Massachusetts
  01605</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Address of principal executive offices, including zip code)</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">(510) 748-4900</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Registrant&#146;s telephone number, including area code)</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Former name or former address, if changed since last report)</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:normal;">Check the
  appropriate box below if the Form&nbsp;8-K filing is intended to simultaneously
  satisfy the filing obligation of the registrant under any of the following
  provisions:</font></b></h4>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></b></h4>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Wingdings" style="font-size:10.0pt;font-weight:normal;">o</font></b><font size="2" style="font-size:10.0pt;font-weight:normal;">&nbsp;&nbsp;&nbsp;Written communications pursuant to Rule&nbsp;425 under
  the Securities Act (17 CFR 230.425)</font></h4>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></b></h4>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Wingdings" style="font-size:10.0pt;font-weight:normal;">o</font></b><font size="2" style="font-size:10.0pt;font-weight:normal;">&nbsp;&nbsp;&nbsp;Soliciting material pursuant to Rule&nbsp;14a-12 under
  the Exchange Act (17 CFR 240.14a-12)</font></h4>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></b></h4>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Wingdings" style="font-size:10.0pt;font-weight:normal;">o</font></b><font size="2" style="font-size:10.0pt;font-weight:normal;">&nbsp;&nbsp;&nbsp;Pre-commencement communications pursuant to Rule&nbsp;14d-2(b)&nbsp;under
  the Exchange Act (17 CFR 240.14d-2(b)</font></h4>
  
  <h4 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></b></h4>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="2" style="font-size:10.0pt;">&nbsp;&nbsp;&nbsp;</font><font size="2" style="font-size:10.0pt;">Pre-commencement communications pursuant
  to Rule&nbsp;13e-4(c)&nbsp;under the Exchange Act (17 CAR 240.13e-4(c))</font></p>
  
  <div style="border:none;border-bottom:double windowtext 6.0pt;padding:0in 0in 0in 0in;">
  
  <p style="border:none;margin:0in 0in .0001pt;padding:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
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  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='',FILE='C:\JMS\brosent\08-14935-1\task2951579\14935-1-ba.htm',USER='brosent',CD='May 20 19:24 2008' -->
  
  
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  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">ITEM 8.01&#160; Other Events.</font></b></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">As previously reported in
  the Form&nbsp;12b-25 filed by the Advanced Cell Technology,&nbsp;Inc. (the &#147;Company&#148;)
  with the Securities and Exchange Commission on May&nbsp;16, 2008, the Company
  was unable to file its Quarterly Report on Form&nbsp;10-Q for the quarterly
  period ended March&nbsp;31, 2008 (the &#147;Form&nbsp;10-Q&#148;), by the required filing
  deadline of May&nbsp;15, 2008, without unreasonable effort or expense. The
  filing of the Form&nbsp;12b-25 afforded the Company an additional period of
  time until May&nbsp;20, 2008 to file the Form&nbsp;10-Q and still be considered
  timely in making that filing. While the Company has been diligently preparing
  the Form&nbsp;10-Q (including the financial statements contained therein), the
  Company was unable to file the Form&nbsp;10-Q by the extended deadline. The
  Company currently anticipates that it will file the Form&nbsp;10-Q as promptly
  as practicable.</font></p>
  
  <p style="margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Because of its failure to
  timely file its Form&nbsp;10-Q, the Company does not meet the &#147;adequate current
  public information&#148; requirement contained in Rule&nbsp;144 promulgated under
  the Securities Act of 1933, as amended, and the Company&#146;s shareholders may not
  rely on Rule&nbsp;144 for the resale of shares of common stock held for less
  than twelve (12) months until the Company files the Form&nbsp;10-Q.</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2</font></p>
  
  <div style="margin:0in 0in .0001pt;text-autospace:none;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='2',FILE='C:\JMS\brosent\08-14935-1\task2951579\14935-1-ba.htm',USER='brosent',CD='May 20 19:24 2008' -->
  
  
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  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">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.</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
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    <td width="56%" valign="top" style="padding:0in .7pt 0in .7pt;width:56.66%;">
    <h3 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;text-indent:0in;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></b></h3>
    </td>
    <td width="43%" colspan="2" valign="top" style="padding:0in .7pt 0in .7pt;width:43.34%;">
    <h3 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;text-indent:0in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">ADVANCED CELL
    TECHNOLOGY, INC.</font></b></h3>
    </td>
   </tr>
   <tr>
    <td width="56%" valign="top" style="padding:0in .7pt 0in .7pt;width:56.66%;">
    <h3 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;text-indent:0in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></b></h3>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.42%;">
    <h3 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;text-indent:0in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></b></h3>
    </td>
    <td width="38%" valign="top" style="padding:0in .7pt 0in .7pt;width:38.92%;">
    <h3 style="font-weight:bold;margin:0in 0in .0001pt;page-break-after:auto;text-indent:0in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></b></h3>
    </td>
   </tr>
   <tr>
    <td width="56%" valign="top" style="padding:0in .7pt 0in .7pt;width:56.66%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.42%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">By:&nbsp;</font></p>
    </td>
    <td width="38%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:38.92%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/ William M.
    Caldwell, IV</font></p>
    </td>
   </tr>
   <tr>
    <td width="56%" valign="top" style="padding:0in .7pt 0in .7pt;width:56.66%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.42%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="38%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:38.92%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">William M.
    Caldwell, IV</font></p>
    </td>
   </tr>
   <tr>
    <td width="56%" valign="top" style="padding:0in .7pt 0in .7pt;width:56.66%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.42%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="38%" valign="top" style="padding:0in .7pt 0in .7pt;width:38.92%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Chief Executive
    Officer</font></p>
    </td>
   </tr>
   <tr>
    <td width="56%" valign="top" style="padding:0in .7pt 0in .7pt;width:56.66%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.42%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="38%" valign="top" style="padding:0in .7pt 0in .7pt;width:38.92%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="56%" valign="top" style="padding:0in .7pt 0in .7pt;width:56.66%;">
    <p style="margin:0in 0in .0001pt;page-break-after:auto;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Dated:
    May&nbsp;21, 2008</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.42%;">
    <p style="margin:0in 0in .0001pt;page-break-after:auto;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="38%" valign="top" style="padding:0in .7pt 0in .7pt;width:38.92%;">
    <p style="margin:0in 0in .0001pt;page-break-after:auto;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
   </tr>
  </table>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3</font></p>
  
  <div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
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metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "a08-14935_18k.htm", "description": "8-K", "secsgml_size_bytes": 18799}]
metadata_filer: {"company-data": {"conformed-name": "ADVANCED CELL TECHNOLOGY, INC.", "cik": "0001140098", "assigned-sic": "2834", "irs-number": "870656515", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-50295", "film-number": "08850507"}, "business-address": {"street1": "381 PLANTATION STREET", "city": "WORCESTER", "state": "MA", "zip": "01605", "phone": "508-756-1212"}, "mail-address": {"street1": "381 PLANTATION STREET", "city": "WORCESTER", "state": "MA", "zip": "01605"}, "former-company": [{"former-conformed-name": "A.C.T. Holdings, Inc.", "date-changed": "20050303"}, {"former-conformed-name": "A.C.T Holdings, Inc.", "date-changed": "20050207"}, {"former-conformed-name": "ACT Holdings Inc.", "date-changed": "20050204"}]}
text: 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):
  May 20, 2008
  ADVANCED CELL TECHNOLOGY, INC.
  (Exact name of registrant as specified in its charter)
  Delaware
  000-50295
  87-0656515
  (State or other jurisdiction
  of incorporation)
  (Commission File Number)
  (IRS Employer Identification Number)
  381 Plantation Street Worcester, Massachusetts
  01605
  (Address of principal executive offices, including zip code)
  (510) 748-4900
  (Registrant's telephone number, including area code)
  (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:
  o
  Written communications pursuant to Rule 425 under
  the Securities Act (17 CFR 230.425)
  o
  Soliciting material pursuant to Rule 14a-12 under
  the Exchange Act (17 CFR 240.14a-12)
  o
  Pre-commencement communications pursuant to Rule 14d-2(b) under
  the Exchange Act (17 CFR 240.14d-2(b)
  o
  Pre-commencement communications pursuant
  to Rule 13e-4(c) under the Exchange Act (17 CAR 240.13e-4(c))
  ITEM 8.01  Other Events.
  As previously reported in
  the Form 12b-25 filed by the Advanced Cell Technology, Inc. (the "Company")
  with the Securities and Exchange Commission on May 16, 2008, the Company
  was unable to file its Quarterly Report on Form 10-Q for the quarterly
  period ended March 31, 2008 (the "Form 10-Q"), by the required filing
  deadline of May 15, 2008, without unreasonable effort or expense. The
  filing of the Form 12b-25 afforded the Company an additional period of
  time until May 20, 2008 to file the Form 10-Q and still be considered
  timely in making that filing. While the Company has been diligently preparing
  the Form 10-Q (including the financial statements contained therein), the
  Company was unable to file the Form 10-Q by the extended deadline. The
  Company currently anticipates that it will file the Form 10-Q as promptly
  as practicable.
  Because of its failure to
  timely file its Form 10-Q, the Company does not meet the "adequate current
  public information" requirement contained in Rule 144 promulgated under
  the Securities Act of 1933, as amended, and the Company's shareholders may not
  rely on Rule 144 for the resale of shares of common stock held for less
  than twelve (12) months until the Company files the Form 10-Q.
  2
  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.
  ADVANCED CELL
    TECHNOLOGY, INC.
  By:
  /s/ William M.
    Caldwell, IV
  William M.
    Caldwell, IV
  Chief Executive
    Officer
  Dated:
    May 21, 2008
  3