UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D/A

Under the Securities Exchange Act of 1934

(Amendment No. 10)*

MariaDB plc

(Name of Issuer)

Ordinary Shares, $0.01 nominal value per share

(Title of Class of Securities)

G5920M100

(CUSIP Number)

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

April 24, 2024

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box ☒

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d -7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D/A

Item 2. Identity and Background.

This Amendment No. 10 (the “Amendment”) hereby amends the Schedule 13D initially filed by Runa Capital Fund II, L.P., Runa Capital II (GP), Runa Capital Opportunity Fund I, L.P., Runa Capital Opportunity I (GP) and Runa Ventures I Limited (collectively, the “Runa Entities”) with the Securities and Exchange Commission (the “SEC”) on September 12, 2023 (the “Original Schedule 13D”), as amended by Amendment No. 1 to the Original Schedule 13D filed by the Runa Entities with the SEC on September 18, 2023 (“Amendment No. 1”), Amendment No. 2 to the Original Schedule 13D filed by the Runa Entities with the SEC on September 21, 2023 (“Amendment No. 2”), Amendment No. 3 to the Original Schedule 13D filed by the Runa Entities with the SEC on September 25, 2023 (“Amendment No. 3”), Amendment No. 4 to the Original Schedule 13D filed by the Runa Entities with the SEC on September 29, 2023 (“Amendment No. 4”), Amendment No. 5 to the Original Schedule 13D filed by the Runa Entities with the SEC on October 13, 2023 (“Amendment No. 5”), Amendment No. 6 to the Original Schedule 13D filed by the Runa Entities with the SEC on January 16, 2024 (“Amendment No. 6”), Amendment No. 7 to the Original Schedule 13D filed by the Runa Entities and Michael “Monty” Widenius with the SEC on February 20, 2024 (“Amendment No. 7”), Amendment No. 8 to the Original Schedule 13D filed with the SEC on March 21, 2024 (“Amendment No. 8”) by the Runa Entities, Smartfin Management BV, a private limited company organized and existing under the laws of Belgium (“Smartfin Management”), Smartfin Capital NV, a public limited company organized and existing under the laws of Belgium (“Smartfin Capital NV”), Smartfin Capital II CommV, a limited partnership organized and existing under the laws of Belgium (“Smartfin Capital II,” and together with Smartfin Capital NV, the “Smartfin Funds”), Bart Luyten, a citizen of Belgium (“Mr. Luyten”), and Jürgen Ingels, a citizen of Belgium (“Mr. Ingels,” and together with Smartfin Management, the Smartfin Funds and Mr. Luyten, the “Smartfin Entities”), Michael “Monty” Widenius, and Open Ocean Opportunity Fund I Ky, a Finish limited partnership (kommandiittiyhtiö), Open Ocean Fund Two Ky, a Finish limited partnership (kommandiittiyhtiö), Patrik Backman, and Ralf Wahlsten (“Mr. Wahlsten,” and together with Open Ocean Opportunity Fund I Ky, Open Ocean Fund Two Ky and Mr. Backman, the “Open Ocean Entities”), and Amendment No. 9 to the Original Schedule 13D filed by the Runa Entities, Mr. Widenius, the Smartfin Entities and the Open Ocean Entities with the SEC on April 1, 2024 (“Amendment No. 9” and together with the Amendment, Amendment No. 1, Amendment No. 2, Amendment No. 3, Amendment No. 4, Amendment No. 5, Amendment No. 6, Amendment No. 7 and Amendment No. 8, collectively the “Schedule 13D”). This Schedule 13D relates to the ordinary shares (the “Ordinary Shares”) of MariaDB plc (“Issuer” or the “Company”). The address of Issuer is 699 Veterans Blvd., Redwood City, CA 94063 and its jurisdiction of incorporation is Ireland. Capitalized terms used but not defined herein have the meanings given to such terms in the Original Schedule 13D or applicable amendment thereto.

This Amendment also amends that statement on Schedule 13D filed by the Smartfin Entities with the SEC on October 12, 2023.

This Amendment is being filed to disclose the events set forth in Item 4.

Item 3. Source or Amount of Funds or Other Consideration

The information in Item 4 is incorporated herein by reference.

Item 4. Purpose of the Transaction

Item 4 of the Schedule 13D is amended to add the following:

Loan Purchase Agreement

On April 24, 2024, the Runa Entities and Meridian Topco LLC (“Topco”) entered into that certain Loan Purchase Agreement (the “Purchase Agreement”) pursuant to which Topco purchased from RP Ventures LLC (“RPV”) all of RPV’s right, title, and interest in, to and under the Note for a purchase price of $66.9 million.

Under the terms of the Purchase Agreement, RPV and the Runa Entities agreed on their behalf and on behalf of their affiliates and other related parties (for the avoidance of doubt, not including Issuer) that during the Restricted Period (as defined below), they would not directly or indirectly through any other person (i) object to, challenge, or commence any legal proceedings against Topco or its related parties with respect to, their acquisition of debt or equity securities in Issuer (collectively, the “Contemplated Transactions”), (ii) engage in any action that would reasonably be expected to adversely interfere with, impede, delay, or otherwise affect Topco’s or one of its affiliates’ consummation of any Contemplated Transaction with certain exceptions, (iii) solicit, initiate or knowingly encourage any proposal or offer to Issuer that constitutes or would reasonably be expected to lead to an alternative transaction to any Contemplated Transaction with other person), (iv) initiate or participate in any communication with third parties with the intention of discouraging or dissuading them from proceeding with any transaction with Topco or one of its affiliates with respect to the debt or equity securities of Issuer, (v) enter into any agreement, purchase agreement, letter of intent, tender agreement, or similar agreement with respect to an alternative transaction to a Contemplated Transaction, (vi) effect or seek, offer or propose to effect, or participate in, knowingly facilitate or knowingly encourage any other person to effect or seek, offer or propose to effect or participate in, any acquisition of any equity interest (or beneficial ownership thereof), or rights or options to acquire any equity interest (or beneficial ownership thereof), any material assets, or any indebtedness or businesses of Issuer, or (vii) take any action that would reasonably be expected to result in a request by a court of competent jurisdiction or a governmental authority to disclose, or would reasonably be expected to cause or require Topco, Issuer or any of their respective related parties to disclose or make a public announcement regarding, any confidential information of Issuer; provided, that, nothing shall restrict the Runa Entities from disposing of any equity securities of Issuer after December 31, 2024 that any of them hold as of April 24, 2024, or from taking any actions in furtherance thereof.

“Restricted Period” means the period commencing on April 24, 2024 and ending on the earlier of (x) April 24, 2027, and (y) the date that (1) no amounts are due or payable under the Note or any other related Note document to Topco or any permitted assignee that is an affiliate of Topco, (2) any person (whether a single purchaser or related group of purchasers), other than Topco or any of its related parties that constitute a group as defined under Rule 13d-5(b)(1) promulgated under the Securities Exchange Act of 1934, as amended, acquires in a single transaction or series of related transactions equity securities of Issuer and its Subsidiaries representing more than fifty percent (50%) of the outstanding debt or equity interests in Issuer and its subsidiaries, and (3) neither Topco nor any of its related parties holds any debt or equity interest in Issuer and its subsidiaries.

The foregoing description of the Purchase Agreement is qualified in its entirety by reference to the full text of the Purchase Agreement, a copy of which is attached hereto as Exhibit 99.20 and is incorporated herein by reference.

Irrevocable Undertakings

On April 24, 2024, Meridian Bidco LLC (“Bidco”), an affiliate of K1 Investment Management, LLC, as manager of K5 Private Investors, L.P., announced the terms of its recommended cash offer to acquire the entire issued and to be issued share capital of Issuer for $0.55 per share (the “Cash Offer”); or, as an alternative to the Cash Offer, eligible shareholders of Issuer could elect to receive one unlisted, unregistered non-voting Class B unit of Topco (the “Unlisted Unit Alternative” and with the Cash Offer, collectively, the “Offer”). In connection with the Offer, the Reporting Persons entered into Deeds of Irrevocable Undertakings in which they each agreed to accept or elect (i) the Cash Offer or alternatively (if Bidco or certain affiliates of Bidco elect to switch to a scheme of arrangement with respect to Issuer under the Irish Companies Act 2014) the scheme of arrangement under the Companies Act 2014 or (ii) other than the Runa Entities, the Unlisted Unit Alternative (the “Irrevocable Undertakings”). The Irrevocable Undertakings shall lapse and cease to have any effect on and from the earliest of the following occurrences:

The foregoing description of the Irrevocable Undertakings is qualified in its entirety by reference to the full text of the form of Irrevocable Undertaking, a copy of which is attached hereto as Exhibit 99.21 and is incorporated herein by reference.

Item 5. Interest in Securities of the Issuer

Dissolution of Group

In connection with the Offer, RPV, the Smartfin Entities, the Open Ocean Entities and Mr. Widenius entered into a Letter Agreement (the “Letter Agreement”) in which they agreed to dissolve the group (as defined pursuant to Rule 13d-5(b)(1)) that they collectively had formed with respect to their ownership of Ordinary Shares and which was disclosed in Amendment No. 8. The Letter Agreement provides that, upon the sale by the Runa Entities (which continue to remain a group, as defined under Rule 13d-5(b)(1)) to Bidco of all of the Ordinary Shares that they own, RPV agreed to promptly pay: $1,905,163 to Smartfin Capital; $1,094,837 to Smartfin Capital II; and $1,250,000 to the Open Ocean Entities.

The foregoing description of the Letter Agreement is qualified in its entirety by reference to the full text of the Letter Agreement, a copy of which is attached hereto as Exhibit 99.22 and is incorporated herein by reference.

Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.

The information set forth in Item 4 and Item 5 is incorporated herein by reference.

Item 7. Materials to be Filed as Exhibits

SCHEDULE 13D/A

SIGNATURE

After reasonable inquiry and to the best of the knowledge and belief of the undersigned, the undersigned certifies that the information set forth in this Amendment to the Statement on Schedule 13D is true, complete and correct.

ATTACHMENTS / EXHIBITS

LOAN PURCHASE AGREEMENT, DATED AS OF APRIL 24, 2024, BY AND AMONG RP VENTURES LLC, RUNA CAPITAL II (GP), RUNA CAPITAL OPPORTUNITY I (GP), RUNA VENTURES I LIMITED AND MERIDIAN TOPCO LLC

FORM OF DEED OF IRREVOCABLE UNDERTAKING

LETTER AGREEMENT, BY AND BETWEEN RP VENTURES LLC, SMARTFIN CAPITAL II COMMV, SMARTFIN CAPITAL NV, SMARTFIN MANAGEMENT BV, OPEN OCEAN OPPORTUNITY FUND I KY, OPEN OCEAN FUND TWO KY, MICHAEL WIDENIUS, PATRIK BACKMAN, AND RALF WAHLSTEN