Filed by Infinera Corporation

Pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12

under the Securities Exchange Act of 1934

Subject Company: Infinera Corporation

Commission File No.: 001-33486

The following communication was first made available on June 27, 2024.

Infinera SVP of Worldwide Sales Email to Infinera Global Sales

Important Action for You: Comms Tools and Guidelines for Informing Customers and Partners of Nokia’s Acquisition Announcement

All:

As you should have seen already in David’s all-employee email, today we announced in a joint press release that Infinera has entered into a definitive agreement to be acquired by Nokia. David’s email to all employees can also be found on the Infinera Hub.

As highlighted in the customer and partner communications we have prepared for you, we believe the combined company will provide significant value for our global customers and partners, and it is critical that we immediately reach out to our key contacts to inform them of this important development. Attached are two OFTs with messaging for this purpose: one to send to customers and one to send to partners. While you will need to customize the message by adding your contact’s name and your signature, please DO NOT alter the content. Also, here is a link to a dedicated resource page on the Infinera Hub where you can find an internal-only Q&A reference document that will prepare you to respond to potential inquiries. Please familiarize yourself with this information prior to your outreach. We will make every effort to keep customers and partners informed as more information becomes available.

While we are limited as to what information we can share at this time, these communications tools reinforce the significant value that we expect to result from our combined strengths, including greater scale, global reach, financial stability, and deeper R&D resources to accelerate time to market for our products and solutions.

Please remember that until the close, we continue to operate as separate and independent companies and it remains critical that we continue to serve our customers with excellence as an independent company. Importantly, please remember and abide by the following:

• You should under no circumstances engage with anyone at Nokia, even if both Nokia and Infinera are present in your customer account. To do so carries serious penalties, even beyond jeopardizing the deal itself;

• You must not encourage or permit your customer to share confidential information about Nokia with you: stop any such conversation immediately, politely but firmly;

• You should at all times avoid speculating about the shape of a possible future portfolio, geographic footprint, etc. Not only has no decision been taken on any such matter, but no decision can be taken until the deal is approved and integration planning has taken place.

Thank you for your support, and please do not hesitate to reach out to me or your regional sales leaders if you have any questions.

Additional Information and Where to Find It; Participants in the Solicitation

Infinera Corporation (“Infinera”), the members of Infinera’s board of directors and certain of Infinera’s executive officers are participants in the solicitation of proxies from stockholders in connection with the pending acquisition of Infinera (the “Transaction”). In connection with the Transaction, Nokia (“Nokia Corporation”) intends to file with the U.S. Securities and Exchange Commission (the “SEC”) a registration statement on Form F-4 that will include a proxy statement of Infinera and that also will constitute a prospectus of Nokia with respect to shares of Nokia’s ordinary shares to be issued in the Transaction, which will be represented by American depositary shares (such registration statement, the “Proxy Statement/Prospectus”).

Christine Bucklin, Greg Dougherty, David Heard, Sharon Holt, Roop Lakkaraju, Paul Milbury, Amy Rice, George Riedel and David Welch, all of whom are members of Infinera’s board of directors, and Nancy Erba, Infinera’s chief financial officer, are participants in Infinera’s solicitation. Information regarding such participants, including their direct or indirect interests, by security holdings or otherwise, will be included in the Proxy Statement/Prospectus and other relevant documents to be filed with the SEC in connection with the Transaction. Additional information about such participants is available under the captions “Our Board of Directors,” “Our Pay” and “Our Stockholders—Security Ownership of Certain Beneficial Owners and Management” in Infinera’s definitive proxy statement in connection with its 2024 Annual Meeting of Stockholders (the “2024 Proxy Statement”), which was filed with the SEC on May 17, 2024 (which is available at https://www.sec.gov/ix?doc=/Archives/edgar/data/1138639/000113863924000128/infn-20240517.htm), as amended on June 4, 2024 (available at https://www.sec.gov/Archives/edgar/data/1138639/000113863924000162/infn2024proxystatementdef1.htm). To the extent that holdings of Infinera’s securities have changed since the amounts printed in the 2024 Proxy Statement, such changes have been or will be reflected on Statements of Change in Ownership on Form 4 filed with the SEC (which are available at https://www.sec.gov/cgi-bin/own-disp?action=getissuer&CIK=0001138639). Information regarding Infinera’s transactions with related persons is set forth in the 2024 Proxy Statement under the caption “Certain Relationships and Related Party Transactions.” Certain illustrative information regarding the payments to that may be owed, and the circumstances in which they may be owed, by Infinera to its named executive officers in a change of control of Infinera is set forth in the 2024 Proxy Statement under the caption “Estimated Payments and Benefits Upon Termination, Change of Control or Death/Disability.”

Promptly after the Proxy Statement/Prospectus is declared effective by the SEC, Infinera will mail the Proxy Statement/Prospectus and a WHITE proxy card to each stockholder entitled to vote at the special meeting to consider the Transaction. BEFORE MAKING ANY VOTING OR INVESTMENT DECISION, SECURITY HOLDERS OF INFINERA AND NOKIA ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS (INCLUDING ANY AMENDMENTS OR SUPPLEMENTS THERETO) AND ANY OTHER RELEVANT DOCUMENTS THAT INFINERA OR NOKIA WILL FILE WITH THE SEC WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT INFINERA, NOKIA AND THE TRANSACTION.

Stockholders may obtain free of charge, when filed, the Proxy Statement/Prospectus, any amendments or supplements thereto, and any other relevant documents filed by Infinera or Nokia with the SEC in connection with the Transaction at the SEC’s website (http://www.sec.gov). Copies of the Proxy Statement/Prospectus, any amendments or supplements thereto, and any other relevant documents filed by Infinera with the SEC in connection with the Transaction will also be available, free of charge, at Infinera’s investor relations website (https://investors.infinera.com/), or by emailing Infinera’s investor relations department (apassi@infinera.com). Copies of the Proxy Statement/Prospectus, any amendments or supplements thereto, and any other relevant documents filed by Nokia with the SEC in connection with the Transaction will also be available, free of charge, at Nokia’s investor relations website (https://www.nokia.com/about-us/investors/), or by emailing Nokia’s investor relations department (investor.relations@nokia.com).

No Offer or Solicitation

This communication is not a proxy statement or solicitation of a proxy, consent or authorization with respect to any securities or in respect of the Transaction and does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote of approval, and there will not be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offering of securities will be made except by means of a prospectus meeting the requirements of Section 10 of the U.S. Securities Act of 1933.

Cautionary Note Regarding Forward-Looking Statements

Certain statements contained in this communication may be characterized as forward-looking under the Private Securities Litigation Reform Act of 1995. These statements involve a number of risks, uncertainties and other factors that could cause actual results to differ materially.

Statements in this communication that are forward-looking may include statements regarding: (1) the Transaction; (2) the expected timing of the closing of the Transaction; (3) considerations taken into account in approving and entering into the Transaction; (4) the anticipated benefits to, or impact of, the Transaction on Nokia’s and Infinera’s businesses; and (5) expectations for Nokia and Infinera following the closing of the Transaction. There can be no assurance that the Transaction will be consummated.

Risks and uncertainties that could cause actual results to differ materially from those indicated in the forward-looking statements, in addition to those identified above, include: (1) the possibility that the conditions to the closing of the Transaction are not satisfied, including the risk that required approvals from Infinera’s stockholders for the Transaction or required regulatory approvals to consummate the Transaction are not obtained, on a timely basis or at all; (2) the occurrence of any event, change or other circumstance that could give rise to a right to terminate the Transaction; (3) possible disruption related to the Transaction to the current plans, operations and business relationships of Nokia and Infinera, including through the loss of customers and employees; (4) the amount of the costs, fees, expenses and other charges incurred by Nokia and Infinera

related to the Transaction; (5) the possibility that the stock prices of Nokia or Infinera could fluctuate during the pendency of the Transaction and may decline if the Transaction is not completed; (6) for both Nokia and Infinera, the possible diversion of management’s time and attention from ongoing business operations and opportunities; (7) the response of competitors and other market participants to the Transaction; (8) potential litigation relating to the Transaction; (9) uncertainty as to the timing of completion of the Transaction and the ability of each party to consummate the Transaction; and (10) the other risks and uncertainties detailed in the periodic reports that Nokia and Infinera file with the SEC. All forward-looking statements in this communication are based on information available to Nokia and Infinera as of the date of this communication, and, except as required by law, neither Nokia nor Infinera assumes any obligation to update the forward-looking statements provided to reflect events that occur or circumstances that exist after the date on which they were made.