<SEC-DOCUMENT>0001193125-25-000645.txt : 20250102
<SEC-HEADER>0001193125-25-000645.hdr.sgml : 20250102
<ACCEPTANCE-DATETIME>20250102161303
ACCESSION NUMBER:		0001193125-25-000645
CONFORMED SUBMISSION TYPE:	424B3
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20250102
DATE AS OF CHANGE:		20250102

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			C3is Inc.
		CENTRAL INDEX KEY:			0001951067
		STANDARD INDUSTRIAL CLASSIFICATION:	DEEP SEA FOREIGN TRANSPORTATION OF FREIGHT [4412]
		ORGANIZATION NAME:           	01 Energy & Transportation
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			1T
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		424B3
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-276430
		FILM NUMBER:		25502160

	BUSINESS ADDRESS:	
		STREET 1:		331 KIFISSIAS AVENUE
		STREET 2:		ERITHREA
		CITY:			ATHENS
		STATE:			J3
		ZIP:			14561
		BUSINESS PHONE:		011-30-210-625-0001

	MAIL ADDRESS:	
		STREET 1:		331 KIFISSIAS AVENUE
		STREET 2:		ERITHREA
		CITY:			ATHENS
		STATE:			J3
		ZIP:			14561
</SEC-HEADER>
<DOCUMENT>
<TYPE>424B3
<SEQUENCE>1
<FILENAME>d883835d424b3.htm
<DESCRIPTION>424B3
<TEXT>
<HTML><HEAD>
<TITLE>424B3</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE" STYLE="line-height:Normal">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Filed Pursuant to Rule 424(b)(3) </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration Nos. <FONT STYLE="white-space:nowrap">333-276430</FONT> and <FONT STYLE="white-space:nowrap">333-276597</FONT> </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>PROSPECTUS SUPPLEMENT NO. 1 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>(TO PROSPECTUS DATED
DECEMBER 13, 2024) </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>C3IS INC. </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This is a
supplement (&#147;Prospectus Supplement&#148;) to the prospectus, dated December 13, 2024 (&#147;Prospectus&#148;), of C3is Inc. (the &#147;Company&#148;), which forms a part of the Company&#146;s Registration Statement on Form <FONT
STYLE="white-space:nowrap">F-1</FONT> (Registration Nos. <FONT STYLE="white-space:nowrap">333-276430</FONT> and <FONT STYLE="white-space:nowrap">333-276597),</FONT> as amended or supplemented from time to time. This Prospectus Supplement is being
filed to update and supplement the information included in the Prospectus with the information contained in our Report on Form <FONT STYLE="white-space:nowrap">6-K,</FONT> furnished to the U.S. Securities and Exchange Commission on January 2, 2025
(the &#147;Form <FONT STYLE="white-space:nowrap">6-K&#148;).</FONT> Accordingly, we have attached the Form <FONT STYLE="white-space:nowrap">6-K</FONT> to this Prospectus Supplement. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This Prospectus Supplement should be read in conjunction with, and delivered with, the Prospectus and is qualified by reference to the
Prospectus except to the extent that the information in this Prospectus Supplement supersedes the information contained in the Prospectus. This Prospectus Supplement is not complete without, and may not be delivered or utilized except in connection
with, the Prospectus, including any amendments or supplements to it. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:12pt; font-family:Times New Roman"><B>Investing in
our securities involves a high degree of risk. See &#147;<U>Risk Factors</U>&#148; beginning on page 9 of the Prospectus for a discussion of information that should be considered in connection with an investment in our securities. </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or
determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense. </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>The date of
this prospectus supplement is January 2, 2025. </B></P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B><FONT
STYLE="white-space:nowrap">FORM&nbsp;6-K</FONT></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>REPORT OF
FOREIGN PRIVATE ISSUER </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>PURSUANT
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">TO&nbsp;RULE&nbsp;13a-16&nbsp;OR&nbsp;15d-16</FONT></FONT></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>UNDER
THE SECURITIES EXCHANGE ACT OF 1934 </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>For the month of January 2025 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Commission <FONT STYLE="white-space:nowrap">File&nbsp;Number&nbsp;001-41717</FONT></B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>C3IS INC. </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Translation
of registrant&#146;s name into English) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>331 Kifissias
Avenue Erithrea 14561 Athens, Greece </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Address of principal executive office) </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Indicate by check mark whether the registrant files or will file annual reports under cover
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">of&nbsp;Form&nbsp;20-F&nbsp;or&nbsp;Form&nbsp;40-F.</FONT></FONT></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">Form&nbsp;20-F&#8194;&#9746;&#8195;&#8195;&#8195;Form&nbsp;40-F&#8194;&#9744;</FONT></FONT></P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION CONTAINED IN
<FONT STYLE="white-space:nowrap">THIS&nbsp;FORM&nbsp;6-K&nbsp;REPORT</FONT></B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Reverse Stock Split </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">On December&nbsp;31, 2024, C3is Inc. (the &#147;Company&#148;) filed an amendment to its Restated Articles of Incorporation, to effectuate a
reverse stock split of the Company&#146;s issued and outstanding shares of common stock, par value of $0.01 per share. A copy of the amendment is attached hereto as Exhibit 4.1. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Effective as of 11:59 p.m. Eastern time on December&nbsp;31, 2024, the Company effected <FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap">a&nbsp;one-for-2.5&nbsp;reverse</FONT></FONT> stock split of its shares of common stock, and the Company&#146;s common stock began trading on a split-adjusted basis on The Nasdaq Capital Market as of the opening of trading
on January&nbsp;2, 2025. The reverse stock split reduced the number of outstanding shares of the Company&#146;s common stock from approximately 10.6&nbsp;million to approximately 4.2&nbsp;million and affected all outstanding shares of common stock.
No fractional shares were issued in connection to the reverse split. Stockholders who would otherwise hold a fractional share of the Company&#146;s common stock received a cash payment in lieu of such fractional share. The Company&#146;s outstanding
warrants and Series A Convertible Preferred Stock will be proportionately adjusted to increase the exercise price and reduce the number of shares issuable upon exercise to reflect the reverse stock split. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The exercise price of the Class&nbsp;B-1, B-2, C-1 and C-2 Warrants, and accordingly the conversion price of the Series&nbsp;A Convertible
Preferred Stock, will be further adjusted to the lowest daily volume weighted average price during the period commencing five consecutive trading days immediately preceding and the five consecutive trading days following the effective time of the
reverse split (if lower than the then current exercise price), with the Class&nbsp;B-1 and C-1 warrants also being exercisable pursuant to an alternative cashless exercise exchange option, and the number of shares of common stock issuable upon
exercise will be proportionately adjusted such that the aggregate exercise price of such warrants as of their original issuance date will remain unchanged. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The par value and other terms of the Company&#146;s shares of common stock were not affected by the reverse stock split. The Company&#146;s
post-reverse split common shares have a new CUSIP number, Y18284 151, and continue to trade on the Nasdaq Capital Market under the symbol &#147;CISS&#148;. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">A copy of the new form of stock certificate for the Company&#146;s post-reverse stock split shares of common stock is attached hereto as
Exhibit 4.2. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Attached to this report on <FONT STYLE="white-space:nowrap">Form&nbsp;6-K&nbsp;as</FONT> Exhibit 99.1 is a copy of the press
release dated December&nbsp;30, 2024 titled &#147;C3is Inc. Announces Reverse Stock Split&#148;. </P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXHIBIT INDEX </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD></TD>

<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD WIDTH="94%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Articles of Amendment to Restated Articles of Incorporation.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Form of Common Stock Certificate.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Press Release, dated December&nbsp;30, 2024.</TD></TR>
</TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">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, thereunto duly authorized. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Date: January&nbsp;2, 2025 </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="12%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="87%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">C3IS INC.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Nina Pyndiah</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Name:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Nina Pyndiah</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Title:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Chief Financial Officer</TD></TR>
</TABLE></DIV>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 4.1 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">ARTICLES OF AMENDMENT </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">TO </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">AMENDED AND RESTATED ARTICLES OF INCORPORATION </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">OF </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">C3IS INC. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Under Section&nbsp;90 of the </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Republic of the Marshall Islands Business Corporations Act </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">C3IS INC., a corporation incorporated in and existing under the law of the Republic of the Marshall Islands (the &#147;Corporation&#148;),
hereby certifies as follows: </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(a) The name of the Corporation is: C3IS INC. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(b) The Corporation was originally incorporated by filing Articles of Incorporation in the Republic of The Marshall Islands on July&nbsp;25,
2022. Amended and Restated Articles of Incorporation were filed with the Registrar of Corporations of the Republic of the Marshall Islands on June&nbsp;13, 2023, as amended by the Articles of Amendment filed with the Registrar of Corporations of the
Republic of the Marshall Islands on April&nbsp;11, 2024 (as so amended, restated and corrected, the &#147;Articles of Incorporation&#148;). A Statement of Designation was filed pursuant to Section&nbsp;35(5) of the Business Corporations Act on
June&nbsp;20, 2023 in respect to the rights, preferences and privileges of the 5.00% Series A Cumulative Convertible Perpetual Preferred Stock of the Corporation. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(c) The Amended and Restated Articles of Incorporation are hereby amended by inserting the following as a new paragraph into Section FOURTH
immediately following the last paragraph therein: </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:9%; font-size:10pt; font-family:Times New Roman">(e) <U>Reverse Stock Split</U>. As of 11:59 p.m. Eastern time on December&nbsp;31, 2024
(the &#147;Reverse Stock Split Effective Date&#148;), each <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">two-and-a-half</FONT></FONT></FONT> (2.5) shares of Common Stock issued and outstanding
immediately prior to the Reverse Stock Split Effective Date either issued and outstanding or held by the Corporation as treasury stock shall be combined into one (1)&nbsp;validly issued, fully paid and
<FONT STYLE="white-space:nowrap">non-assessable</FONT> share of Common Stock without any further action by the Corporation or the holder thereof (the &#147;Reverse Stock Split&#148;); provided that no fractional shares shall be issued to any holder
and that in lieu of issuing any such fractional shares, fractional shares resulting from the Reverse Stock Split will be rounded down to the nearest whole share and provided, further, that stockholders who would otherwise be entitled to receive
fractional shares because they hold a number of shares not evenly divisible by the ratio of the Reverse Stock Split will receive a cash payment (without interest and subject to applicable withholding taxes) in an amount per share equal to the
closing price per share of Common Stock on the Nasdaq Stock Market on the trading day immediately preceding the Reverse Stock Split Effective Date, as adjusted for the reverse stock split as appropriate. Each certificate, if any, that immediately
prior to the Reverse Stock Split Effective Date represented shares of Common Stock (&#147;Old Certificates&#148;), shall thereafter represent that number of shares of Common Stock into which the shares of Common Stock represented by the Old
Certificate shall have been combined, subject to the elimination of fractional shares as described above. The reverse stock split described in this paragraph shall not change the number of shares of Common Stock authorized to be issued or the par
value of the Common Stock. No change was made to the number of registered shares of Preferred Stock the Corporation is authorized to issue or to the par value of the Preferred Stock. </P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(d) This amendment to the Amended and Restated Articles of Incorporation was authorized by
actions of the Board of Directors and shareholders of the Corporation as required by the BCA. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">IN WITNESS WHEREOF, the Corporation has
caused these Articles of Amendment to Amended and Restated Articles of Incorporation to be signed as of the 31st day of December, 2024, by its Chief Executive Officer, who hereby affirms and acknowledges, under penalty of perjury, that these
Articles of Amendment are the act and deed of the Corporation and that the facts stated herein are true. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">C3IS INC.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Diamantis Andriotis</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Name: Diamantis Andriotis</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Title: Chief Executive Officer</TD></TR>
</TABLE></DIV>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 4.2 </B></P>
<P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>COMMON STOCK </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>CUSIP No.
Y18284 151 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="51%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="48%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"><B>Certificate Number</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"><B>Shares</B></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>C3IS INC. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>FORMED UNDER THE LAWS OF THE REPUBLIC OF THE MARSHALL ISLANDS </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">THIS CERTIFIES THAT _______________________________________ </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">is
the owner of<B> </B><B>_______________________________________________</B> </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">FULLY-PAID AND
<FONT STYLE="white-space:nowrap">NON-ASSESSABLE</FONT> SHARES OF COMMON STOCK, PAR VALUE $0.01 PER SHARE, OF </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><I></I><B><I>C3is Inc. (hereinafter called
the &#147;Company&#148;)</I></B><I>, transferable on the books of the Company by the holder hereof in person or by duly authorized attorney upon surrender of this Certificate properly endorsed. This Certificate and the shares represented hereby are
issued and shall be held subject to all the provisions of the Articles of Incorporation, as amended, and Bylaws of the Corporation, to all of which each holder, by acceptance hereof, assents. </I></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Witness the signatures of the duly authorized officers of the Company. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Dated&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;, 20&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195; [Affix
Corporate Seal] </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="48%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="1%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="49%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>Diamantis Andriotis, Chief
Executive Officer, President and Director</I></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"><I>&#8194;</I></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><I>Nina Pyndiah,
Secretary</I></P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">COUNTERSIGNED AND REGISTERED </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>EQUINITI TRUST COMPANY, LLC </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">TRANSFER AGENT AND REGISTRAR
</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="6%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="93%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">&nbsp;&#8195;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Authorized Signature</TD></TR>
</TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">C3IS INC. WILL FURNISH WITHOUT CHARGE TO EACH SHAREHOLDER WHO SO REQUESTS, A FULL STATEMENT OF THE
DESIGNATION, RELATIVE RIGHTS, PREFERENCES AND LIMITATIONS OF EACH CLASS OF SHARES OF THE COMPANY AUTHORIZED TO BE ISSUED AND THE DESIGNATION, RELATIVE RIGHTS, PREFERENCES AND LIMITATIONS OF EACH SERIES, WHICH ARE FIXED AND THE AUTHORITY OF THE BOARD
OF DIRECTORS TO DESIGNATE AND FIX THE RELATIVE RIGHTS, PREFERENCES AND LIMITATIONS OF OTHER SERIES. SUCH REQUEST MAY BE MADE TO THE OFFICE OF THE SECRETARY OF THE COMPANY OR TO THE TRANSFER AGENT. THE BOARD OF DIRECTORS MAY REQUIRE THE OWNER OF A
LOST OR DESTROYED SHARES CERTIFICATE, OR HIS LEGAL REPRESENTATIVES, TO GIVE THE COMPANY A BOND TO INDEMNIFY IT AND ITS TRANSFER AGENTS AND REGISTRARS AGAINST ANY CLAIM THAT MAY BE MADE AGAINST THEM ON ACCOUNT OF THE ALLEGED LOSS OR DESTRUCTION OF
ANY SUCH CERTIFICATE. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were
written out in full according to applicable laws or regulations: </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="8%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="23%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="24%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="14%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="8%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="15%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">TEN&nbsp;COM</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP>&#151;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">as tenants in common</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">UNIF GIFT MIN ACT &#151;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">Custodian</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">TEN ENT</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP>&#151;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">as tenants by the entireties</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">&#8194;&#8195;&#8195;(Cust)&#8195;&#8195;&#8194;</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">&#8194;&#8195;&#8195;(Minor)&#8195;&#8195;&#8194;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">JT TEN</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP>&#151;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">as joint tenants with right</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Under Uniform Gifts to Minors Act</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">of survivorship and not as</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">&nbsp;&#8195;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">tenants in common</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">(State)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Additional abbreviations may also be used though not in the above list. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><I>For value received, ___________________________________ hereby sells, assigns and transfers unto </I></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="100%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE</TD></TR>
</TABLE>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="51%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="48%"></TD></TR>


<TR STYLE="font-size:1px; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP STYLE="BORDER:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt">&#8195;</FONT></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="100%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="99%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><I>____________________________________________________________________________________________ Shares</I></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"><I>represented by the within Certificate, and does hereby irrevocably constitute and appoint</I></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><I>____________________________________________________________________________________________Attorney</I></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"><I>to transfer the said shares on the books of the within named Corporation with full power of substitution in the premises.</I></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="17%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="74%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"><I>Dated</I></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">&nbsp;&#8195;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">NOTICE:</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="80%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="100%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SIGNATURE(S) GUARANTEED:</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">THE SIGNATURE(S) SHOULD BE
GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE
<FONT STYLE="white-space:nowrap">17Ad-15.</FONT></P></TD></TR>
</TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">2 </P>

</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 99.1 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>C3IS INC. ANNOUNCES REVERSE STOCK SPLIT </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><I>To be effective January&nbsp;2, 2025 </I></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><I>Aiming to meet the minimum bid price requirement for maintaining listing on Nasdaq </I></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>ATHENS, GREECE</B>&nbsp;&#150; December&nbsp;30, 2024 &#150; C3IS INC. (the &#147;Company&#148;) (Nasdaq: CISS) today announced that its board of directors
has determined to effect a <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">one-for-two-and-a-half</FONT></FONT></FONT></FONT></FONT>
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">(1-for-2.5)</FONT></FONT> reverse stock split of the Company&#146;s common stock, par value $0.01 per share. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The reverse stock split will take effect at 11:59 pm Eastern Time on December&nbsp;31, 2024, and the Company&#146;s common stock will begin trading on a
split-adjusted basis on The Nasdaq Capital Market (&#147;Nasdaq&#148;) as of the opening of trading on January&nbsp;2, 2025.&nbsp;The CUSIP number of Y18284 151 will be assigned to the Company&#146;s common stock when the reverse stock split becomes
effective. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">When the reverse stock split becomes effective, every two and <FONT STYLE="white-space:nowrap">one-half</FONT> (2.5) of the Company&#146;s
issued shares of common stock will be combined into one issued share of common stock, without any change to the par value per share.&nbsp;This will reduce the number of outstanding shares of common stock from approximately 10.6&nbsp;million shares
to approximately 4.2&nbsp;million shares. The Company&#146;s outstanding warrants and Series A Convertible Preferred Stock will be proportionately adjusted to increase the exercise price and reduce the number of shares issuable upon exercise. With
respect to the Company&#146;s Class&nbsp;B Warrants and Class&nbsp;C Warrants, the exercise price and number of shares issuable upon exercise will be adjusted further in an adjustment period ending on the fifth trading day after the effective time
of the reverse split pursuant to the terms of such warrants. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">No fractional shares will be issued in connection with the reverse stock
split.&nbsp;Stockholders who would otherwise hold a fraction of a share of common stock of the Company will receive a cash payment in lieu thereof at a price equal to that fraction of a share to which the stockholder would otherwise be entitled,
multiplied by the closing price of the Company&#146;s common stock on Nasdaq on December&nbsp;31, 2024 (as adjusted for the reverse split). </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Stockholders
with shares held in book-entry form or through a bank, broker, or other nominee are not required to take any action and will see the consequence of the reverse stock split reflected in their accounts on or after January&nbsp;2, 2025.&nbsp;Such
beneficial holders may contact their bank, broker, or nominee for more information. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The reverse stock split ratio approved by the board of directors is
within the, previously disclosed, range of ratios for a reverse stock split authorized by the stockholders of the Company, within three years of the <FONT STYLE="white-space:nowrap">spin-out</FONT> of the Company. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The purpose of the reverse stock split is to increase the market price of the Company&#146;s common stock. The Company believes that the reverse stock split
will increase the market price for its common stock and allow it to satisfy the minimum bid price requirement for maintaining listing on Nasdaq. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Forward-Looking Statements </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Matters discussed in this
release may constitute forward-looking statements within the meaning of the safe harbor provisions of Section&nbsp;27A of the Securities Act of 1933 and Section&nbsp;21E of the Securities Exchange Act of 1934, including statements with respect to
the C3is Inc.&#146;s ability to maintain compliance with Nasdaq&#146;s continued listing standards and remain listed on Nasdaq or other major stock exchange and other statements that are forward looking. Forward-looking statements reflect our
current views with respect to future events and financial performance and may include statements concerning plans, objectives, goals, strategies, future events or performance and underlying assumptions and other statements, which are other than
statements of historical facts. The forward-looking </P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
statements in this release are based upon various assumptions. Although C3is Inc. believes that these assumptions were reasonable when made, because these assumptions are inherently subject to
significant uncertainties and contingencies which are difficult or impossible to predict and are beyond our control, C3is Inc. cannot assure you that it will achieve or accomplish these expectations, beliefs or projections. Important factors that,
in our view, could cause actual results to differ materially from those discussed in the forward-looking statements include risks discussed in our filings with the U.S. Securities and Exchange Commission (the &#147;SEC&#148;) and the following: the
strength of world economies and currencies, global market conditions, including changes in charter hire rates and vessel values, charter counterparty performance, changes in demand that may affect attitudes of time charterers to scheduled and
unscheduled <FONT STYLE="white-space:nowrap">dry-dockings,</FONT> shipyard performance, changes in C3is Inc.&#146;s operating expenses, including bunker prices, drydocking and insurance costs, ability to fund the remaining purchase price for one of
our drybulk vessels, ability to obtain financing and comply with covenants in our financing arrangements, actions taken by regulatory authorities, potential liability from pending or future litigation, domestic and international political
conditions, the conflict in Ukraine and related sanctions, the conflict in Israel and Gaza, potential disruption of shipping routes due to ongoing attacks by Houthis in the Red Sea and Gulf of Aden or accidents and political events or acts by
terrorists. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Risks and uncertainties are further described in reports filed by C3is Inc. with the SEC. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>ABOUT C3IS INC. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">C3is Inc. is a ship-owning company
providing dry bulk and crude oil seaborne transportation services. The Company owns four vessels, three handysize drybulk carriers with a total capacity of 97,664 deadweight tons (dwt) and an Aframax oil tanker with a cargo carrying capacity of
approximately 115,800 dwt, resulting with a fleet total capacity of 213,464 dwt. C3is Inc.&#146;s shares of Common Stock are listed on the Nasdaq Capital Market and trade under the symbol &#147;CISS.&#148; </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">For further information, please contact: </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Company Contact:
</B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Nina Pyndiah </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chief Financial Officer </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">C3is INC. </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">00-30-210-6250-001</FONT></FONT></FONT></FONT> </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="white-space:nowrap">E-mail:</FONT> info@c3is.pro </P>
</DIV></Center>

</BODY></HTML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
