<SEC-DOCUMENT>0001752724-23-276836.txt : 20231212
<SEC-HEADER>0001752724-23-276836.hdr.sgml : 20231212
<ACCEPTANCE-DATETIME>20231212105732
ACCESSION NUMBER:		0001752724-23-276836
CONFORMED SUBMISSION TYPE:	N-CEN
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20230930
FILED AS OF DATE:		20231212
DATE AS OF CHANGE:		20231212
EFFECTIVENESS DATE:		20231212

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			abrdn Life Sciences Investors
		CENTRAL INDEX KEY:			0000884121
		IRS NUMBER:				043147016
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			0930

	FILING VALUES:
		FORM TYPE:		N-CEN
		SEC ACT:		1940 Act
		SEC FILE NUMBER:	811-06565
		FILM NUMBER:		231480328

	BUSINESS ADDRESS:	
		STREET 1:		1900 MARKET STREET
		STREET 2:		SUITE 200
		CITY:			PHILADELPHIA
		STATE:			PA
		ZIP:			19103
		BUSINESS PHONE:		6177728515

	MAIL ADDRESS:	
		STREET 1:		1900 MARKET STREET
		STREET 2:		SUITE 200
		CITY:			PHILADELPHIA
		STATE:			PA
		ZIP:			19103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TEKLA LIFE SCIENCES INVESTORS
		DATE OF NAME CHANGE:	20141015

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	H&Q LIFE SCIENCES INVESTORS
		DATE OF NAME CHANGE:	19920929
</SEC-HEADER>
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            <principalFileNo>8-69787</principalFileNo>
            <principalCrdNo>000283942</principalCrdNo>
            <principalLei>549300HN4UKV1E2R3U73</principalLei>
            <principalStateCountry principalState="US-NY" principalCountry="US"/>
            <principalTotalPurchaseSale>160000.00000000</principalTotalPurchaseSale>
          </principalTransaction>
          <principalTransaction>
            <principalName>CuraSen Therapeutics, Inc.</principalName>
            <principalFileNo>N/A</principalFileNo>
            <principalCrdNo>N/A</principalCrdNo>
            <principalLei>N/A</principalLei>
            <principalStateCountry principalState="US-CA" principalCountry="US"/>
            <principalTotalPurchaseSale>497418.43000000</principalTotalPurchaseSale>
          </principalTransaction>
          <principalTransaction>
            <principalName>State Street Bank and Trust Company</principalName>
            <principalFileNo>N/A</principalFileNo>
            <principalCrdNo>N/A</principalCrdNo>
            <principalLei>571474TGEMMWANRLN572</principalLei>
            <principalStateCountry principalState="US-MA" principalCountry="US"/>
            <principalTotalPurchaseSale>2787024000.00000000</principalTotalPurchaseSale>
          </principalTransaction>
          <principalTransaction>
            <principalName>AMOLYT PHARMA</principalName>
            <principalFileNo>N/A</principalFileNo>
            <principalCrdNo>N/A</principalCrdNo>
            <principalLei>N/A</principalLei>
            <principalStateCountry principalState="US-MA" principalCountry="US"/>
            <principalTotalPurchaseSale>1610455.25000000</principalTotalPurchaseSale>
          </principalTransaction>
        </principalTransactions>
        <principalAggregatePurchase>2849907266.71000000</principalAggregatePurchase>
        <isBrokerageResearchPayment>N</isBrokerageResearchPayment>
        <mnthlyAvgNetAssets>419527241.27000000</mnthlyAvgNetAssets>
      </managementInvestmentQuestion>
    </managementInvestmentQuestionSeriesInfo>
    <closedEndManagementInvestment>
      <securityRelatedItems>
        <securityRelatedItem>
          <description>Common stock</description>
          <securityClassTitle>Tekla Life Sciences Investors</securityClassTitle>
          <commonStocks>
            <commonStock commonStockExchange="XNYS" commonStockTickerSymbol="HQL"/>
          </commonStocks>
        </securityRelatedItem>
      </securityRelatedItems>
      <isRightsOffering>N</isRightsOffering>
      <isSecondaryOffering>N</isSecondaryOffering>
      <isRepurchaseSecurity>N</isRepurchaseSecurity>
      <isDefaultLongTermDebt>N</isDefaultLongTermDebt>
      <isDividendsInArrears>N</isDividendsInArrears>
      <isSecuritiesModified>N</isSecuritiesModified>
      <managementFee>1.06000000</managementFee>
      <netOperatingExpenses>1.35000000</netOperatingExpenses>
      <marketPricePerShare>12.47000000</marketPricePerShare>
      <netAssetValuePerShare>15.00000000</netAssetValuePerShare>
    </closedEndManagementInvestment>
    <attachmentsTab>
      <isIPAReportInternalControl>true</isIPAReportInternalControl>
    </attachmentsTab>
    <signature registrantSignedName="abrdn Life Sciences Investors" signedDate="2023-12-05" signature="Laura Woodward" title="VP of Fund Admin"/>
  </formData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>INTERNAL CONTROL RPT
<SEQUENCE>2
<FILENAME>NCEN_811-06565_15997308_0923.htm
<TEXT>

<HTML>
<HEAD>
   <TITLE>lifesciencesncen.htm - Generated by SEC Publisher for SEC Filing</TITLE>
</HEAD>

<BODY bgcolor="#ffffff">
<a name="page_1"></a><a name="_bclPageBorder1"></a><DIV STYLE="PADDING-RIGHT: 0%; PADDING-LEFT: 0%">
<p style="margin-bottom:20.0pt;margin-left:0in;margin-right:0in;margin-top:0in;page-break-after:avoid;text-align:center;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">Report of Independent Registered Public Accounting
Firm</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">To the Shareholders and Board of
Trustees<br>
abrdn Life Sciences Investors:</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">In planning and performing our audit
of the financial statements of abrdn Life Sciences Investors (formerly, Tekla
Life Sciences Investors) (the Fund) as of and for the year ended
September&nbsp;30,&nbsp;2023, in accordance with the standards of the Public
Company Accounting Oversight Board (United States), we considered the Fund's
internal control over financial reporting, including controls over safeguarding
securities, as a basis for designing our auditing procedures for the purpose of
expressing our opinion on the financial statements and to comply with the
requirements of Form N-CEN, but not for the purpose of expressing an opinion on
the effectiveness of the Fund's internal control over financial reporting.
Accordingly, we express no such opinion.</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">Management of the Fund is responsible
for establishing and maintaining effective internal control over financial
reporting. In fulfilling this responsibility, estimates and judgments by
management are required to assess the expected benefits and related costs of
controls. A company's internal control over financial reporting is a process
designed to provide reasonable assurance regarding the reliability of financial
reporting and the preparation of financial statements for external purposes in
accordance with generally accepted accounting principles. A company's internal
control over financial reporting includes those policies and procedures that
(1) pertain to the maintenance of records that, in reasonable detail,
accurately and fairly reflect the transactions and dispositions of the assets
of the company; (2) provide reasonable assurance that transactions are recorded
as necessary to permit preparation of financial statements in accordance with
generally accepted accounting principles, and that receipts and expenditures of
the company are being made only in accordance with authorizations of management
and directors of the company; and (3) provide reasonable assurance regarding
prevention or timely detection of unauthorized acquisition, use, or disposition
of the company's assets that could have a material effect on the financial
statements.</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">Because of its inherent limitations,
internal control over financial reporting may not prevent or detect
misstatements. Also, projections of any evaluation of effectiveness to future
periods are subject to the risk that controls may become inadequate because of
changes in conditions, or that the degree of compliance with the policies or
procedures may deteriorate.</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">A deficiency in internal control over
financial reporting exists when the design or operation of a control does not
allow management or employees, in the normal course of performing their assigned
functions, to prevent or detect misstatements on a timely basis. A material
weakness is a deficiency, or a combination of deficiencies, in internal control
over financial reporting, such that there is a reasonable possibility that a
material misstatement of the company&#8217;s annual or interim financial statements
will not be prevented or detected on a timely basis.</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">Our consideration of the Fund's
internal control over financial reporting was for the limited purpose described
in the first paragraph and would not necessarily disclose all deficiencies in
internal control that might be material weaknesses under standards established
by the Public Company Accounting Oversight Board (United States). However, we
noted no deficiencies in the Fund's internal control over financial reporting
and its operation, including controls over safeguarding securities, that we
consider to be a material weakness as defined above as of
September&nbsp;30,&nbsp;2023.</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;page-break-after:avoid;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">This
report is intended solely for the information and use of the management and the
Board of Trustees of abrdn Life Sciences Investors (formerly, Tekla Life
Sciences Investors) and the Securities and Exchange </font><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">Commission
and is not intended to be and should not be used by anyone other than these
specified parties.</font></p>
</DIV><HR noshade align="center" width="100%" size=2><DIV STYLE="page-break-before: always">&nbsp;</DIV><a name="page_2"></a><a name="_bclPageBorder2"></a><DIV STYLE="PADDING-RIGHT: 0%; PADDING-LEFT: 0%">


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  <p style="margin-bottom:0in;margin-left:0in;margin-right:0in;margin-top:3.0pt;page-break-after:avoid;"><font face=Arial,sans-serif style="font-size:9.0pt;font-style:normal;font-weight:normal;">&nbsp;</font></p>
  </td>
 <td valign=top width=20% style="padding:0in 0in 0in 0in;">
  <p style="margin-bottom:0in;margin-left:0in;margin-right:0in;margin-top:3.0pt;page-break-after:avoid;"><font face=Arial,sans-serif style="font-size:9.0pt;font-style:normal;font-weight:normal;">&nbsp;</font></p>
  </td>
 <td valign=top width=20% style="padding:0in 0in 0in 0in;">
  <p align=center style="margin-bottom:0in;margin-left:0in;margin-right:0in;margin-top:0in;page-break-after:avoid;text-align:center;"><font face=Arial,sans-serif style="font-size:10.0pt;line-height:12.0pt;">/s/ KPMG LLP</font></p>
  <p style="margin-bottom:0in;margin-left:0in;margin-right:0in;margin-top:3.0pt;page-break-after:avoid;"><font face=Arial,sans-serif style="font-size:9.0pt;font-style:normal;font-weight:normal;">&nbsp;</font></p>
  </td>
 <td valign=top width=20% style="padding:0in 0in 0in 0in;">
  <p style="margin-bottom:0in;margin-left:0in;margin-right:0in;margin-top:3.0pt;page-break-after:avoid;"><font face=Arial,sans-serif style="font-size:9.0pt;font-style:normal;font-weight:normal;">&nbsp;</font></p>
  </td>
 <td valign=top width=20% style="padding:0in 0in 0in 0in;">
  <p style="margin-bottom:0in;margin-left:0in;margin-right:0in;margin-top:3.0pt;page-break-after:avoid;"><font face=Arial,sans-serif style="font-size:9.0pt;font-style:normal;font-weight:normal;">&nbsp;</font></p>
  </td>
 </tr>
</table></div>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;page-break-after:avoid;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;font-style:normal;font-weight:normal;line-height:12.0pt;">Philadelphia,
Pennsylvania<br>
November&nbsp;29,&nbsp;2023</font></p>

<p style="margin-bottom:10.0pt;margin-left:0in;margin-right:0in;margin-top:0in;"><font face=Arial,sans-serif lang=EN-US style="font-size:10.0pt;line-height:12.0pt;">&nbsp;</font></p>




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</DOCUMENT>
</SEC-DOCUMENT>
