<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>SEC FORM 
            4</title>
<style type="text/css">
              .FormData {color: blue; background-color: white; font-size: small; font-family: Times, serif;}
              .FormDataC {color: blue; background-color: white; font-size: small; font-family: Times, serif; text-align: center;}
              .FormDataR {color: blue; background-color: white; font-size: small; font-family: Times, serif; text-align: right;}
              .SmallFormData {color: blue; background-color: white; font-size: x-small; font-family: Times, serif;}
              .FootnoteData {color: green; background-color: white; font-size: x-small; font-family: Times, serif;}
              .FormNumText {font-size: small; font-weight: bold; font-family: arial, helvetica, sans-serif;}
              .FormAttention {font-size: medium; font-weight: bold; font-family: helvetica;}
              .FormText {font-size: small; font-weight: normal; font-family: arial, helvetica, sans-serif; text-align: left;}
              .FormTextR {font-size: small; font-weight: normal; font-family: arial, helvetica, sans-serif; text-align: right;}
              .FormTextC {font-size: small; font-weight: normal; font-family: arial, helvetica, sans-serif; text-align: center;}
              .FormEMText {font-size: medium; font-style: italic; font-weight: normal; font-family: arial, helvetica, sans-serif;}
              .FormULText {font-size: medium; text-decoration: underline; font-weight: normal; font-family: arial, helvetica, sans-serif;}
              .SmallFormText {font-size: xx-small; font-family: arial, helvetica, sans-serif; text-align: left;}
              .SmallFormTextR {font-size: xx-small; font-family: arial, helvetica, sans-serif; text-align: right;}
              .SmallFormTextC {font-size: xx-small; font-family: arial, helvetica, sans-serif; text-align: center;}
              .MedSmallFormText {font-size: x-small; font-family: arial, helvetica, sans-serif; text-align: left;}
              .FormTitle {font-size: medium; font-family: arial, helvetica, sans-serif; font-weight: bold;}
              .FormTitle1 {font-size: small; font-family: arial, helvetica, sans-serif; font-weight: bold; border-top: black thick solid;}
              .FormTitle2 {font-size: small; font-family: arial, helvetica, sans-serif; font-weight: bold;}
              .FormTitle3 {font-size: small; font-family: arial, helvetica, sans-serif; font-weight: bold; padding-top: 2em; padding-bottom: 1em;}
              .SectionTitle {font-size: small; text-align: left; font-family: arial, helvetica, sans-serif; 
              		font-weight: bold; border-top: gray thin solid; border-bottom: gray thin solid;}
              .FormName {font-size: large; font-family: arial, helvetica, sans-serif; font-weight: bold;}
              .CheckBox {text-align: center; width: 5px; cell-spacing: 0; padding: 0 3 0 3; border-width: thin; border-style: solid;  border-color: black:}
              body {background: white;}
      </style>
</head>
<body>SEC Form 4 
   <table width="100%" border="0" cellspacing="0" cellpadding="4">
<tr>
<td width="20%" colspan="2" valign="top" align="center" class="FormName">FORM 4</td>
<td rowspan="2" width="60%" valign="middle" align="center">
<span class="FormTitle">UNITED STATES SECURITIES AND EXCHANGE COMMISSION</span><br><span class="MedSmallFormText">Washington, D.C. 20549</span><br><br><span class="FormTitle">STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP</span><br><br><span class="MedSmallFormText">Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934</span><br><span class="MedSmallFormText">or Section 30(h) of the Investment Company Act of 1940</span>
</td>
<td rowspan="2" width="20%" valign="top" align="center"><table width="100%" border="1" summary="OMB Approval Status Box">
<tr><td class="FormTextC">OMB APPROVAL</td></tr>
<tr><td><table width="100%" border="0" summary="OMB Interior Box">
<tr>
<td class="SmallFormText" colspan="3">OMB Number:</td>
<td class="SmallFormTextR">3235-0287</td>
</tr>
<tr><td class="SmallFormText" colspan="4">Estimated average burden</td></tr>
<tr>
<td class="SmallFormText" colspan="3">hours per response:</td>
<td class="SmallFormTextR">0.5</td>
</tr>
</table></td></tr>
</table></td>
</tr>
<tr valign="middle">
<td><table width="100%" border="1" cellpadding="0" cellspacing="0"><tr><td>  </td></tr></table></td>
<td class="SmallFormText">Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. 
         <i>See</i>

         Instruction 1(b).</td>
</tr>
</table>
<table width="100%" border="1" cellspacing="0" cellpadding="4">
<tr>
<td rowspan="3" width="35%" valign="top">
<span class="MedSmallFormText">1. Name and Address of Reporting Person<sup>*</sup></span><table border="0" width="100%"><tr><td><a href="/cgi-bin/browse-edgar?action=getcompany&amp;CIK=0001030575">FORMELA JEAN FRANCOIS</a></td></tr></table>
<hr width="98%">
<table border="0" width="100%"><tr>
<td width="33%" class="MedSmallFormText">(Last)</td>
<td width="33%" class="MedSmallFormText">(First)</td>
<td width="33%" class="MedSmallFormText">(Middle)</td>
</tr></table>
<table border="0" width="100%">
<tr><td><span class="FormData">C/O TRANSLATE BIO, INC.</span></td></tr>
<tr><td><span class="FormData">29 HARTWELL AVE</span></td></tr>
</table>
<hr width="98%">
<span class="MedSmallFormText">(Street)</span><table border="0" width="100%"><tr>
<td width="33%"><span class="FormData">LEXINGTON</span></td>
<td width="33%"><span class="FormData">MA</span></td>
<td width="33%"><span class="FormData">02421</span></td>
</tr></table>
<hr width="98%">
<table border="0" width="100%"><tr>
<td width="33%" class="MedSmallFormText">(City)</td>
<td width="33%" class="MedSmallFormText">(State)</td>
<td width="33%" class="MedSmallFormText">(Zip)</td>
</tr></table>
</td>
<td width="35%" valign="top">
<span class="MedSmallFormText">2. Issuer Name <b>and</b> Ticker or Trading Symbol
      </span><br><a href="/cgi-bin/browse-edgar?action=getcompany&amp;CIK=0001693415">Translate Bio, Inc.</a>
     [ <span class="FormData">TBIO</span> ]
   </td>
<td rowspan="2" valign="top">
<span class="MedSmallFormText">5. Relationship of Reporting Person(s) to Issuer
      </span><br><span class="MedSmallFormText">(Check all applicable)</span><table border="0" width="100%">
<tr>
<td width="15%" align="center"><span class="FormData">X</span></td>
<td width="35%" class="MedSmallFormText">Director</td>
<td width="15%" align="center"></td>
<td width="35%" class="MedSmallFormText">10% Owner</td>
</tr>
<tr>
<td align="center"></td>
<td class="MedSmallFormText">Officer (give title below)</td>
<td align="center"></td>
<td class="MedSmallFormText">Other (specify below)</td>
</tr>
<tr>
<td width="15%" align="center"></td>
<td width="35%" align="left" style="color: blue"></td>
<td width="15%" align="center"></td>
<td width="35%" align="left" style="color: blue"></td>
</tr>
</table>
</td>
</tr>
<tr><td valign="top">
<span class="MedSmallFormText">3. Date of Earliest Transaction
         (Month/Day/Year)</span><br><span class="FormData">09/14/2021</span>
</td></tr>
<tr>
<td valign="top">
<span class="MedSmallFormText">4. If Amendment, Date of Original Filed
         (Month/Day/Year)</span><br>
</td>
<td valign="top">
<span class="MedSmallFormText">6. Individual or Joint/Group Filing (Check Applicable Line)
      </span><table border="0" width="100%">
<tr>
<td width="15%" align="center"><span class="FormData">X</span></td>
<td width="85%" class="MedSmallFormText">Form filed by One Reporting Person</td>
</tr>
<tr>
<td width="15%" align="center"></td>
<td width="85%" class="MedSmallFormText">Form filed by More than One Reporting Person</td>
</tr>
</table>
</td>
</tr>
</table>
<table width="100%" border="1" cellspacing="0" cellpadding="4">
<thead>
<tr><th width="100%" valign="top" colspan="11" align="center" class="FormTextC"><b>Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned</b></th></tr>
<tr>
<th width="36%" valign="top" rowspan="2" align="left" class="MedSmallFormText">1. Title of Security (Instr. 
      3)
   </th>
<th width="6%" valign="top" rowspan="2" align="left" class="SmallFormText">2. Transaction Date
      (Month/Day/Year)</th>
<th width="5%" valign="top" rowspan="2" align="left" class="SmallFormText">2A. Deemed Execution Date, if any
      (Month/Day/Year)</th>
<th width="7%" valign="top" colspan="2" align="left" class="SmallFormText">3. Transaction Code (Instr. 
      8)
   </th>
<th width="19%" valign="top" colspan="3" align="left" class="SmallFormText">4. Securities Acquired (A) or Disposed Of (D) (Instr. 
      3, 4 and 5)
   </th>
<th width="11%" valign="top" rowspan="2" align="left" class="SmallFormText">5. 
      Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 
      3 and 4)
   </th>
<th width="9%" valign="top" rowspan="2" align="left" class="SmallFormText">6. Ownership Form: Direct (D) or Indirect (I) (Instr. 
      4)
   </th>
<th width="8%" valign="top" rowspan="2" align="left" class="SmallFormText">7. Nature of Indirect Beneficial Ownership (Instr. 
      4)
   </th>
</tr>
<tr>
<th width="4%" align="center" class="SmallFormText">Code</th>
<th width="3%" align="center" class="SmallFormText">V</th>
<th width="8%" align="center" class="SmallFormText">Amount</th>
<th width="5%" align="center" class="SmallFormText">(A) or (D)</th>
<th width="6%" align="center" class="SmallFormText">Price</th>
</tr>
</thead>
<tbody><tr>
<td align="left"><span class="FormData">Common Stock</span></td>
<td align="center"><span class="FormData">09/14/2021</span></td>
<td align="center"><span class="FormData"></span></td>
<td align="center">
<span class="SmallFormData">S</span><span class="FootnoteData"><sup>(1)</sup></span>
</td>
<td align="center"></td>
<td align="center">
<span class="FormData">2,055,063</span><span class="FootnoteData"><sup>(1)</sup></span>
</td>
<td align="center"><span class="FormData">D</span></td>
<td align="center">
<span class="FormText">$</span><span class="FormData">38</span>
</td>
<td align="center"><span class="FormData">0</span></td>
<td align="center"><span class="FormData">I</span></td>
<td align="left">
<span class="FormData">See Footnote</span><span class="FootnoteData"><sup>(2)</sup></span>
</td>
</tr></tbody>
</table>
<table width="100%" border="1" cellspacing="0" cellpadding="4">
<thead>
<tr><th width="100%" valign="top" colspan="16" align="center" class="FormTextC">
<b>Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned</b><br><b>(e.g., puts, calls, warrants, options, convertible securities)</b>
</th></tr>
<tr>
<th width="13%" valign="top" rowspan="2" align="left" class="SmallFormText">1. Title of Derivative Security (Instr. 
      3)
   </th>
<th width="5%" valign="top" rowspan="2" align="left" class="SmallFormText">2. Conversion or Exercise Price of Derivative Security
   </th>
<th width="5%" valign="top" rowspan="2" align="left" class="SmallFormText">3. Transaction Date
      (Month/Day/Year)</th>
<th width="5%" valign="top" rowspan="2" align="left" class="SmallFormText">3A. Deemed Execution Date, if any
      (Month/Day/Year)</th>
<th width="9%" valign="top" colspan="2" align="left" class="SmallFormText">4. Transaction Code (Instr. 
      8)
   </th>
<th width="10%" valign="top" colspan="2" align="left" class="SmallFormText">5. 
      Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 
      3, 4 and 5)
   </th>
<th width="9%" valign="top" colspan="2" align="left" class="SmallFormText">6. Date Exercisable and Expiration Date 
      (Month/Day/Year)</th>
<th width="17%" valign="top" colspan="2" align="left" class="SmallFormText">7. Title and Amount of Securities Underlying Derivative Security (Instr. 
      3 and 4)
   </th>
<th width="6%" valign="top" rowspan="2" align="left" class="SmallFormText">8. Price of Derivative Security (Instr. 
      5)
   </th>
<th width="6%" valign="top" rowspan="2" align="left" class="SmallFormText">9. 
      Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 
      4)
   </th>
<th width="6%" valign="top" rowspan="2" align="left" class="SmallFormText">10. Ownership Form: Direct (D) or Indirect (I) (Instr. 
      4)
   </th>
<th width="7%" valign="top" rowspan="2" align="left" class="SmallFormText">11. Nature of Indirect Beneficial Ownership (Instr. 
      4)
   </th>
</tr>
<tr>
<th width="4%" valign="bottom" align="center" class="SmallFormText">Code</th>
<th width="4%" valign="bottom" align="center" class="SmallFormText">V</th>
<th width="5%" valign="bottom" align="center" class="SmallFormText">(A)</th>
<th width="5%" valign="bottom" align="center" class="SmallFormText">(D)</th>
<th width="5%" valign="bottom" align="center" class="SmallFormText">Date Exercisable</th>
<th width="4%" valign="bottom" align="center" class="SmallFormText">Expiration Date</th>
<th width="10%" valign="bottom" align="center" class="SmallFormText">Title</th>
<th width="7%" valign="bottom" align="center" class="SmallFormText">Amount or Number of Shares</th>
</tr>
</thead>
<tbody>
<tr>
<td align="left"><span class="SmallFormData">Stock Option (right to buy)</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">10.2</span>
</td>
<td align="center"><span class="SmallFormData">09/14/2021</span></td>
<td align="center"><span class="SmallFormData"></span></td>
<td align="center">
<span class="SmallFormData">S</span><span class="FootnoteData"><sup>(3)</sup></span>
</td>
<td align="center"></td>
<td align="center"></td>
<td align="center"><span class="SmallFormData">18,900</span></td>
<td align="center">
<span class="SmallFormData">
                
            </span><span class="FootnoteData"><sup>(4)</sup></span>
</td>
<td align="center"><span class="SmallFormData">06/17/2029</span></td>
<td align="center"><span class="SmallFormData">Common Stock</span></td>
<td align="center"><span class="FormData">18,900</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">0.00</span>
</td>
<td align="center"><span class="SmallFormData">0</span></td>
<td align="center">
<span class="SmallFormData">D</span><span class="FootnoteData"><sup>(5)</sup></span>
</td>
<td align="left"></td>
</tr>
<tr>
<td align="left"><span class="SmallFormData">Stock Option (right to buy)</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">15.33</span>
</td>
<td align="center"><span class="SmallFormData">09/14/2021</span></td>
<td align="center"><span class="SmallFormData"></span></td>
<td align="center">
<span class="SmallFormData">S</span><span class="FootnoteData"><sup>(3)</sup></span>
</td>
<td align="center"></td>
<td align="center"></td>
<td align="center"><span class="SmallFormData">18,900</span></td>
<td align="center">
<span class="SmallFormData">
                
            </span><span class="FootnoteData"><sup>(6)</sup></span>
</td>
<td align="center"><span class="SmallFormData">06/15/2030</span></td>
<td align="center"><span class="SmallFormData">Common Stcok</span></td>
<td align="center"><span class="FormData">18,900</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">0.00</span>
</td>
<td align="center"><span class="SmallFormData">0</span></td>
<td align="center">
<span class="SmallFormData">D</span><span class="FootnoteData"><sup>(5)</sup></span>
</td>
<td align="left"></td>
</tr>
<tr>
<td align="left"><span class="SmallFormData">Stock Option (right to buy)</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">20.43</span>
</td>
<td align="center"><span class="SmallFormData">09/14/2021</span></td>
<td align="center"><span class="SmallFormData"></span></td>
<td align="center">
<span class="SmallFormData">S</span><span class="FootnoteData"><sup>(3)</sup></span>
</td>
<td align="center"></td>
<td align="center"></td>
<td align="center"><span class="SmallFormData">20,000</span></td>
<td align="center">
<span class="SmallFormData">
                
            </span><span class="FootnoteData"><sup>(7)</sup></span>
</td>
<td align="center"><span class="SmallFormData">06/15/2031</span></td>
<td align="center"><span class="SmallFormData">Common Stock</span></td>
<td align="center"><span class="FormData">20,000</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">0.00</span>
</td>
<td align="center"><span class="SmallFormData">0</span></td>
<td align="center">
<span class="SmallFormData">D</span><span class="FootnoteData"><sup>(5)</sup></span>
</td>
<td align="left"></td>
</tr>
<tr>
<td align="left"><span class="SmallFormData">Stock Option (right to buy)</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">8.34</span>
</td>
<td align="center"><span class="SmallFormData">09/14/2021</span></td>
<td align="center"><span class="SmallFormData"></span></td>
<td align="center">
<span class="SmallFormData">S</span><span class="FootnoteData"><sup>(3)</sup></span>
</td>
<td align="center"></td>
<td align="center"></td>
<td align="center"><span class="SmallFormData">37,800</span></td>
<td align="center">
<span class="SmallFormData">
                
            </span><span class="FootnoteData"><sup>(8)</sup></span>
</td>
<td align="center"><span class="SmallFormData">03/06/2028</span></td>
<td align="center"><span class="SmallFormData">Common Stock</span></td>
<td align="center"><span class="FormData">37,800</span></td>
<td align="center">
<span class="SmallFormText">$</span><span class="SmallFormData">0.00</span>
</td>
<td align="center"><span class="SmallFormData">0</span></td>
<td align="center">
<span class="SmallFormData">D</span><span class="FootnoteData"><sup>(5)</sup></span>
</td>
<td align="left"></td>
</tr>
</tbody>
</table>
<table border="0" width="100%">
<tr><td class="MedSmallFormText"><b>Explanation of Responses:</b></td></tr>
<tr><td class="FootnoteData">1. As of September 14, 2021, Issuer was acquired in a cash tender by an indirect subsidiary of Sanofi, a French societe anonyme at a purchase price of $38.00 per share (the "Tender Offer"), as described more fully in the Schedule 14D-9 filed by the Issuer on August 16, 2021.</td></tr>
<tr><td class="FootnoteData">2. 1,872,115 of these shares are held directly by Atlas Venture Fund VIII, L.P. ("Atlas VIII'').  182,948 of these shares are held directly by Atlas Venture Associates VIII, L.P. ("AVA VIII LP"), the general partner of Atlas VIII.  These shares were previously received by AVA VIII LP in a pro-rata stock distribution pursuant to a Rule 10b5-1 plan established by Atlas VIII.  Atlas Venture Associates VIII, Inc. ("AVA VIII INC") is the sole general partner of AVA VIII LP.  Dr. Formela is a director of AVA VIII INC and disclaims Section 16 beneficial ownership of the securities held by Atlas VIII and Atlas VIII LP, except to the extent of his pecuniary interest therein, if any.  This report shall not be deemed to be an admission that Dr. Formela is the beneficial owner of such shares for the purposes of Section 16 or any other purpose.</td></tr>
<tr><td class="FootnoteData">3. Under the terms of the Tender Offer, Issuer outstanding stock options, if not vested became vested, and all Issuer stock options were converted into cash consideration at the amount of the difference between the exercise price of the option and the Tender Offer price of $38.00 per share.</td></tr>
<tr><td class="FootnoteData">4. This option was granted on June 18, 2019.  The shares underlying this option became fully vested on the date of the Issuer's annual meeting of stockholders following the date of the grant, or June 16, 2020.</td></tr>
<tr><td class="FootnoteData">5. This stock option was granted to the Reporting Person, a director of the Issuer. The proceeds of any sale of shares of common stock issued to the Reporting Person upon exercise of this stock option will be transferred to Atlas Venture Advisors, Inc. and as such, the Reporting Person disclaims ownership of such securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except to the extent of his pecuniary interest therein, if any.</td></tr>
<tr><td class="FootnoteData">6. This option was granted on June 16, 2020. The shares underlying this option became fully vested on the date of the Issuer's annual meeting of stockholders following the date of the grant, or June 16, 2021.</td></tr>
<tr><td class="FootnoteData">7. This option was granted on June 16, 2021. This option will vest and become exercisable in full on the one year anniversary of the date of the award, or if earlier, the date of the Issuer's next annual meeting of stockholders following the date of the grant.</td></tr>
<tr><td class="FootnoteData">8. This option was granted on March 7, 2018, with 25% of the shares underlying the option vesting on March 7, 2019 and thereafter 2.0833% vesting monthly until March 7, 2022.</td></tr>
<tr><td class="FormText"><b>Remarks:</b></td></tr>
<tr><td class="FootnoteData"></td></tr>
</table>
<table width="100%" border="0">
<tr>
<td width="60%"></td>
<td width="20%"><u><span class="FormData">/s/ Frank Castellucci, as attorney-in-fact for Jean-Francois Formela</span></u></td>
<td width="20%"><u><span class="FormData">09/14/2021</span></u></td>
</tr>
<tr>
<td></td>
<td class="MedSmallFormText">** Signature of Reporting Person</td>
<td class="MedSmallFormText">Date</td>
</tr>
<tr><td colspan="3" class="MedSmallFormText">Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.</td></tr>
<tr><td colspan="3" class="MedSmallFormText">* If the form is filed by more than one reporting person, 
                  <i>see</i>

                  Instruction 
                  4

                  (b)(v).</td></tr>
<tr><td colspan="3" class="MedSmallFormText">** Intentional misstatements or omissions of facts constitute Federal Criminal Violations 
                  <i>See</i>

                  18 U.S.C. 1001 and 15 U.S.C. 78ff(a).</td></tr>
<tr><td colspan="3" class="MedSmallFormText">Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, 
                  <i>see</i>

                  Instruction 6 for procedure.</td></tr>
<tr><td colspan="3" class="MedSmallFormText"><b>Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.</b></td></tr>
</table>
</body>
</html>
