Carbios : Amendment to the 2020 Universal Registration Document

Société anonyme (public limited company) with a Board of Directors and capital of

€5,715,130.40

Registered office: Biopôle Clermont-Limagne - 3 rue Emile Duclaux - 63360 Saint-

Beauzire, France

RCS Clermont-Ferrand 531 530 228

AMENDMENT TO THE 2020 UNIVERSAL REGISTRATION DOCUMENT FILED WITH THE AUTORITÉ DES MARCHÉS FINANCIERS (AMF) ON APRIL 14, 2021 UNDER NUMBER D.21-0306

This amendment to the Universal Registration Document was filed on April 30, 2021 with the AMF, as the competent authority in respect of (EU) Regulation no. 2017/1129, without prior approval in accordance with Article 9 of the said regulation.

The Universal Registration Document may be used in support of a public offering of securities or the admission to trading of financial securities on a regulated market if it is supplemented by a transaction note and, if applicable, a summary note and all amendments made to the Universal Registration Document. The set of documents is approved by the AMF in accordance with (EU) Regulation no. 2017/1129.

This amendment updates and must be read in conjunction with the 2020 Universal Registration Document filed with the Autorité des marchés financiers on April 14, 2021 under number D.21-0306. The 2020 Universal Registration Document and this related amendment are available free of charge from Carbios, on the Company's website (www.carbios.com) and the AMF's website (www.amf-france.org).

SUMMARY OF THE AMENDMENT TO THE 2020 UNIVERSAL

REGISTRATION DOCUMENT

1.	Updated information on the person responsible	................................................................ 3
2.	Cross-reference tables .........................................................................................................	4
3.	Press release of April 23, 2021 .............................................................................................	7
4.	Press release of April 26, 2021 ...........................................................................................	10
5.	Press release of April 28, 2021 ...........................................................................................	12

1. Updated information on the person responsible

1.1 Identity of the person responsible for the amendment to the Universal Registration Document

Jean-Claude Lumaret, Chief Executive Officer.

2.1 Declaration by the person responsible

"I certify that the information contained in this amendment is, to the best of my knowledge, correct and does not contain any omissions that would alter its scope."

Saint-Beauzire,

April 30, 2021

Jean-Claude Lumaret

Chief Executive Officer

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2. Cross-reference tables

The cross-reference table below shows the chapters or sub-chapters of the Company's 2020 Universal Registration Document ("URD") subject to an update in this amendment, with direct links to the sections of the corresponding update. This table of contents is drawn up in accordance with Annexes 1 and 2 of Commission Delegated Regulation (EU) 2019/980 of March 14, 2019:

	Annexes 1 and 2 of Delegated Regulation (EU) No.	URD	Update performed
	2019/980	chapters/sections
1	Persons responsible, third-party information,	Chapter 7
	experts' reports and competent authority approval
1.1	Identity of the persons responsible	7.3
1.2	Declaration of the persons responsible	7.3
1.3	Experts' declarations	N/A
1.4	Third-party information	N/A
1.5	Statement from the competent authority	7.5
2	Statutory auditors	7.4
2.1	Principal Statutory Auditors	7.4.1
2.2	Statutory Auditors that resigned or were dismissed	7.4.2
3.	Risk factors	Chapter 3
4	Information concerning the issuer	7.1
4.1	Company name and business name of the issuer	7.1.1
4.2	Place of registration, registration number and LEI of the	7.1.2
	issuer
4.3	Date of incorporation and length of life of the issuer	7.1.3
4.4	Registered office of the Company and legal form,	7.1.4
	applicable legislation, website and other
5	Business overview	Chapter 1
5.1	Main activities	1.4 to 1.6	- Section	1.4.2 of
			the	URD	updated
			by this section 3
			- Section 1.4.5.3 of
			the	URD	updated
			by sections 4 and 5
5.1.1	Nature of transactions carried out by the issuer	1.4; 1.5	- Section	1.4.2 of
			the	URD	updated
			by this section 3
			- Section 1.4.5.3 of
			the	URD	updated
			by sections 4 and 5
5.1.2	New products and/or services	1.6
5.2	Principal markets	1.2
5.3	Important events	7.1.5
5.4	Strategy and objectives	1.3
5.5	Extent of dependence	3.2.1.4
5.6	Competitive position of the issuer	1.4.4; 1.5.4;
		3.2.1.3
5.7	Investments	2.2.4
5.7.1	Material investments	2.2.4.1
5.7.2	Material investments in progress	2.2.4.2
5.7.3	Joint ventures and significant shareholdings	2.2.4.3
5.7.4	Environmental impact of the use of property, plant and	2.2.4.4
	equipment
6	Organizational structure	1.1.4
6.1	Brief description of the group	1.1.3; 1.5; 5.3
6.2	List of significant subsidiaries	2.2.4.3
7	Operating and financial review	2.1
7.1	Financial position	2.1

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	Annexes 1 and 2 of Delegated Regulation (EU) No.	URD	Update performed
	2019/980	chapters/sections
7.1.1	Changes in the issuer's results	2.1.3; 5.1
7.1.2	Likely future development of the issuer's activities and	1.4.3; 1.5.3; 1.6
	its R&D activities
7.2	Operating income	2.1.2; 2.1.3.1
7.2.1	Key factors	2.1.1
7.2.2	Major changes	N/A
8.2	Cash flows of the issuer	2.2.2
8.3	Financing needs and financing structure of the issuer	2.2.3
8.4	Restrictions on the use of the issuer's capital resources	N/A
8.5	Expected sources of funding	2.2.3
9	Regulatory environment	1.2.2; 1.2.3; 3.2.6
10	Trend information	2.3
10.1	Most significant trends	2.3
	Significant change in financial performance
10.2	Known trends that are reasonably likely to have a	2.4
	material effect on the issuer's prospects
11	Profit forecasts or estimates	2.4
12	Administrative, management and supervisory bodies	4.1
	and executive management
12.1	Information concerning the members of the issuer's	4.1.1; 4.1.2
	administrative and management bodies
12.2	Conflicts of interest	4.1.4
13	Remuneration and benefits	4.2
13.1	Compensation and benefits paid	4.2
13.2	Total amounts set aside to provide for pension,	N/A
	retirement or similar benefits
14	Board practices	4.1.5
14.1	Duration of terms of office	4.1.5.1.2.1
14.2	Service contracts	4.1.5.1.2.3
14.3	Information concerning committees	4.1.5.2
14.4	Statement related to corporate governance	4.1.5.2.3
14.5	Implications of future changes in the composition of	N/A
	bodies
15	Employees	1.1.4; 6.4.2
15.1	Human Resources	1.1.4
15.2	Shareholdings and stock options	6.4.2
15.3	Any arrangements for involving the employees in the	N/A
	capital of the issuer
16	Major shareholders	6.1
16.1	Distribution of share capital	6.1.1
16.2	Existence of different voting rights	6.1.2
16.3	Control of the issuer	6.1.3
16.4	Agreements resulting in a change of control	N/A
17	Related-party transactions	4.3
18	Financial information concerning the issuer's assets	Chapter 5
	and liabilities, financial position and profits and
	losses
18.1	Historical financial information	Chapter 5
18.1.1	Audited historical financial information	Chapter 5
18.1.2	Change of accounting key date	N/A
18.1.3	Accounting standards	preamble Chapter
		2; 5.1.4.4
18.1.4	Change in accounting basis	N/A
18.1.5	Breakdown of audited financial information	5.1
18.1.6	Consolidated financial statements	N/A
18.1.7	Date of most recent financial information	5.1
18.2	Interim and other financial information	N/A
18.3	Audit of historical annual financial information	5.2

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