SECOND SUPPLEMENT DATED 20 DECEMBER 2023

TO THE BASE PROSPECTUS DATED 15 MAY 2023

(established as a société anonyme with limited liability in France)

€7,000,000,000

Euro Medium Term Note Programme

This supplement constitutes the second supplement (the "Second Supplement") to, and must be read in conjunction with, the base prospectus dated 15 May 2023 granted approval no. 23-159 on 15 May 2023 and the first supplement dated 3 August 2023 granted approval no. 23-342 on 3 August 2023 (together, the "Base Prospectus") by the Autorité des marchés financiers (the "AMF") prepared by Thales (the "Issuer") with respect to its Euro Medium Term Note Programme (the "Programme"). Terms defined in the Base Prospectus have the same meaning when used in this Second Supplement. The Base Prospectus as supplemented constitutes a base prospectus for the purpose of Regulation (EU) 2017/1129 of the European Parliament and of the Council of 14 June 2017 (as may be amended from time to time, the "Prospectus Regulation").

Application has been made to the AMF for approval of this Second Supplement in its capacity as competent authority pursuant to the Prospectus Regulation.

This Second Supplement has been prepared pursuant to Article 23 of the Prospectus Regulation for the purposes of (a) increasing the aggregate nominal amount of the Notes that may be issued under the Programme and (b) updating the "Recent Developments" section of the Base Prospectus to include certain press releases.

A copy of this Second Supplement will be available on the websites of (i) the Issuer (www.thalesgroup.com) and (ii) the AMF (www.amf-france.org).

To the extent that there is any inconsistency between any statement in this Second Supplement and any other statement in or incorporated by reference in the Base Prospectus, the statements in this Second Supplement will prevail.

Save as disclosed in this Second Supplement, there has been no other significant new factor, material mistake or inaccuracy relating to information included in the Base Prospectus which is capable of affecting the assessment of the Notes to be issued under the Programme since the publication of the Base Prospectus.

INCREASE OF THE PROGRAMME'S MAXIMUM AGGREGATE PRINCIPAL AMOUNT OF NOTES

All references in the Base Prospectus to the maximum aggregate principal amount of Notes that may be outstanding at any one time under Programme should be changed from "EUR 5,000,000,000" to "EUR 7,000,000,000".

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DOCUMENTS INCORPORATED BY REFERENCE

On page 23 of the Base Prospectus, a new paragraph (a) should be added to the list of documents incorporated by reference as the latest quarterly press release shall be incorporated in the Base Prospectus. The numbering of the subsequent paragraphs shall be amended accordingly.

"(a)

the press releasepublished on 31 October 2023 in the English language relating to the Issuer's order intake

and sales for the third quarter of 2023 (the "Q3 2023 Press Release");"

Item 4.1.5 of the cross-reference list in respect of information incorporated by reference on page 24 of the Base Prospectus should be replaced by the following:

"

4.1.5 Any recent events particular to the issuer and which are to a material extent relevant to an evaluation of the issuer's solvency.

Pages 1-8, Q3 2023 Press Release

"

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RECENT DEVELOPMENTS

The below paragraphs relating to certain press releases of the Issuer should be inserted at the end of the section "Recent Developments" on page 74 of the Base Prospectus. For the avoidance of doubt, references to page numbers in the footnotes therein (if applicable) are to the pages in such press releases, not the pages in this Second Supplement.

"The following press release was published by the Issuer on 1 December 2023 in relation to the Issuer's proposal to transfer pension scheme obligations to the insurance company Rothesay:

"Pensions de-risking: Thales secures £2.7 billion full insurance transaction for Thales UK

Pensions

  • Thales has completed an agreement to transfer the entirety of its £2.7 billion Thales UK Pension Scheme obligations to the insurance company Rothesay
  • Impacts on 2023 reported financial statements:
  1. P&L settlement charge of approximately £400 million (one-off)o Total cash-out of approximately £850 million (one-off)

Thales (Euronext Paris: HO) announced today a transaction to fully insure its Thales UK Pension Scheme obligations.

Under the agreement, Thales will transfer approximately £2.7 billion of its gross pension obligations and related plan assets to Rothesay. The insurance transaction secures the benefits for all members of the Scheme, which includes defined benefit liabilities for 10,512 pensioners and dependents, and a further 5,915 deferred members.

This transaction is in line with the capital allocation strategy of Thales. Thanks to this operation, the Group is de-risking its balance sheet from the potential volatility of pension schemes' valuation arising from market risks such as inflation, interest rates as well as longevity risks.

In connection with this agreement, Thales expects to recognize a one-offP&L settlement charge of approximately £400 million in the fourth quarter of 2023, and a total one-off cash-outof approximately £850 million during the same period. These P&L and cash impacts will not affect the FY23 EBIT1 nor the FY23 free operating cash flow1 of the company.

Following the completion of this transaction, Thales will no longer have to contribute annually for £75 million to reduce the pension funding shortfall. Lastly, the Group expects a neutral impact on its adjusted net income.

The full "buy-out" will be effective by mid-2025 at the latest, after a first technical full "buy-in" step implemented from 1st December 2023. Terms and conditions related to the full "buy-out" have already been contractually accepted by Rothesay. As part of this transaction, Thales will buy back

£165 million of assets with an average 5 years duration.

Pascal Bouchiat, CFO at Thales, said: "We are very satisfied with this transaction that will result in de- risking and simplifying Thales balance sheet while providing a positive outcome for current and past Thales employees. Thales and Thales UK Trustees have been working intensively to help provide security to its over 16,000 members."

1 Non-GAPP financial indicators, see definitions page 2

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Definitions of non-GAAP financial indicators

  • EBIT, an adjusted operating indicator, corresponds to current operating income, plus the share in net income of equity affiliates, before the impact of entries recorded as part of business combinations (amortization of assets valued when determining the purchase price allocation, other expenses directly related to acquisitions). In application of IFRS5, it does not include the contribution to EBIT from discontinued operations.
  • Free operating cash flow corresponds to the net cash flow from operations before contributions to reduce the pension deficit in the United Kingdom, and after deducting net operating investments. To facilitate comparison with adjusted net income, free cash flow from operations is obtained by summing free cash flow from continuing operations and free cash flow from discontinued operations."

The following press release was published by the Issuer on 4 December in relation to its acquisition of Imperva:

"Thales completes the acquisition of Imperva, creating a global leader in cybersecurity

  • Combination creating one of the world's 5 leading companies focused on protecting the heart of the digital ecosystem: applications, data and identities
  • With the integration of Imperva starting in January, Thales will help organizations discover and protect sensitive data anywhere, manage access and secure all paths to it
  • North America is now the second largest country of operations for Thales
  • Imperva is Thales' ninth acquisition in the digital security area over the last nine years, and the second largest in the Group's history after Gemalto

MEUDON - [4 December 2023] - Thales (Euronext Paris: HO) announces today that it has completed the acquisition of Imperva, earlier than expected (previously foreseen at the beginning of 2024). This is a key milestone for Thales, creating a global leader in cybersecurity, with more than 5,800 cybersecurity experts across 68 countries and

€2.4bn in cybersecurity revenue expected in 2024, including civil and defence activities, with double-digit growth expected thereafter. This transaction will generate significant value creation for Thales' shareholders in line with the targets communicated in July 2023, when announcing the acquisition. In addition, the profile of Thales' Digital Identity and Security (DIS) activity will be significantly enhanced with new financial targets by 2027 (2024-2027 organic sales growth of +6 to +7% and 2027 EBIT margin at 16.5%).

Patrice Caine, Chairman and Chief Executive Officer of Thales, said: "The acquisition of the US company Imperva is an important day for Thales, as it marks a new step in the expansion of our global cybersecurity capabilities for enterprises and governments around the world. We are very excited to welcome the Imperva teams to Thales. The combination of our entities' values and our joint commitment to a future of trust will create significant synergies, business opportunities and major market innovations. With ever-increasingcyber threats against business and government digital infrastructure, Thales is now uniquely positioned to help customers protect the heart of their digital ecosystem: applications, data and identities."

Data-Centric Security spanning across Applications, Data and Identities

Together, Thales and Imperva will help customers address cybersecurity challenges that have increased rapidly in frequency, severity, and complexity, with the most comprehensive solutions for the broadest range of application, data security, and identity use cases. These three market segments combined are forecasted to grow significantly in the coming years. According to analysts' forecast, worldwide end-user spending is projected to total around $20 billion in 2024.

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With the addition of Imperva, Thales' expanded cybersecurity portfolio now offers a highly complementary combination of solutions to help customers secure applications, data and identities across their entire digital ecosystem:

  • Application Security: Unified protection for every application and API in the cloud, on- premises, or in a hybrid model. The market leading product suite includes Web Application Firewall (WAF), Distributed Denial of Service attack (DDoS) Protection, Advanced Bot Protection, Application Programming Interface (API) Security, a developer-friendly Content Delivery Network (CDN), and Runtime Application Self-Protection (RASP).
  • Data Security: Protection and control of access to sensitive data anywhere whether at rest, in motion or in use. The product suite includes the CipherTrust Data Security Platform, Imperva Data Security Fabric, as well as the Luna and payShield Hardware Security Modules, often used as the root of trust for cryptographic operations.
  • Identity & Access Management: seamless, secure and trusted access to applications and digital services for customers, employees and partners. The product suite includes the OneWelcome Identity Platform and SafeNet Trusted Access.

"As a long-standing partner of both Thales and Imperva, we at Exclusive Networks are delighted with the combination of two companies that we know and value," said Jesper Trolle, CEO Exclusive Networks. "This acquisition marks a key step in Thales' ambition to become a global leader in cybersecurity, reinforcing its strength in data security and expanding into the buoyant application security market. With this new combined value proposition, Thales will be uniquely positioned to offer even more innovative and effective solutions to address the growing security and compliance challenges faced by organisations around the world."

This is Thales' ninth acquisition in the digital security area over the last nine years, and the second largest in the Group's history after Gemalto, world leader in digital security. After the completed acquisitions of Tesserent, the leading player in cybersecurity in Australia, S21sec & Excellium, two major players in cybersecurity consulting, integration and managed services in Europe, and

Thales in North America

With 6,200 employees1 and €2.4 billion revenues2 in North America in 2022, and approximately 50% of the free float shares held by U.S. shareholders, Thales already has a strong presence in the region. The acquisition of Imperva increases Thales' digital security workforce in North America by almost a third.

Each year, Thales invests €4 billion in R&D, of which €1 billion is self-financed3. The Group is fully committed to supporting Imperva's customers and augmenting its solutions through accelerated innovations. As an innovator, Thales has a total of 20,000 patents in its portfolio, more than 50% of these involve key technologies related to AI, generative artificial intelligence, cybersecurity, big data, the cloud, augmented reality and quantum technologies.

Thales has 77,000 employees4 in 68 countries. In 2022, the Group generated sales of €17.6 billion.

  1. Including GTS employees
  2. Without GTS revenues
  3. Group-leveldata
  4. Excluding the Transport business, which is currently being divested"

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GENERAL INFORMATION

On page 95 of the Base Prospectus, paragraph 5 of the "General Information" section shall be replaced in its entirety by the below paragraph:

"5. Except as disclosed in this Base Prospectus (including the "Recent Developments" section), there has been no significant change in the financial position or financial performance of the Issuer or of the Group since 30 September 2023 and no material adverse change in the prospects of the Issuer since 31 December 2022."

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PERSON RESPONSIBLE FOR THE INFORMATION GIVEN IN THIS SECOND SUPPLEMENT

Person responsible for this Second Supplement

Thales, 4 rue de la Verrerie 92190 MEUDON, France

Declaration by the person responsible for this Second Supplement

I declare, to the best of my knowledge, that the information contained in this Base Prospectus is in accordance with the facts and that it contains no omission which could affect its import.

Thales

4 rue de la Verrerie

92190 MEUDON

France

duly represented by Jean-Claude CLIMEAU on 20 December 2023

VP, Treasury, Trade & Corporate Finance

Autorité des marchés financiers

This Second Supplement has been approved on 20 December 2023 by the AMF in its capacity as competent authority under Regulation (EU) 2017/1129, as amended.

The AMF has approved this Second Supplement after having verified that the information contained in the Base Prospectus, as supplemented, is complete, coherent and comprehensible in accordance with Regulation (EU) 2017/1129, as amended.

This approval should not be considered as a favourable opinion on the Issuer and on the quality of the Notes described in the Base Prospectus, as supplemented. Investors should make their own assessment of the opportunity to invest in such Notes.

This Second Supplement has been given the following approval number: 23-519.

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Attachments

Disclaimer

THALES SA published this content on 22 December 2023 and is solely responsible for the information contained therein. Distributed by Public, unedited and unaltered, on 25 December 2023 20:41:39 UTC.