SEC Form 6-K filed by Grifols S.A.

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16
UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of May 2026

Commission File No. 001-35193

Grifols, S.A.

(Translation of registrant’s name into English)

Avinguda de la Generalitat, 152-158

Parc de Negocis Can Sant Joan

Sant Cugat del Valles 08174

Barcelona, Spain

(Address of registrant’s principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F x                                          Form 40-F ¨

Grifols, S.A.

TABLE OF CONTENTS

Grifols, S.A.   Avinguda de la Generalitat 152-158 08174 Sant Cugat del Vallès Barcelona - SPAIN   Tel. [34] 935 710 500 Fax [34] 935 710 267   www.grifols.com

THIS DOCUMENT CONSTITUTES A TRANSLATION INTO ENGLISH OF THE OFFICIAL SPANISH VERSION. IN CASE OF DISCREPANCIES, THE OFFICIAL SPANISH VERSION SHALL PREVAIL.

GRIFOLS, S.A.

ORDINARY GENERAL SHAREHOLDERS' MEETING

The Board of Directors has resolved to call the shareholders of Grifols, S.A. (the “Company”) to the Ordinary General Shareholders' Meeting that will be held on first call, at the Company's registered office, that is, Parque Empresarial Can Sant Joan, Avinguda de la Generalitat, 152-158, 08174 Sant Cugat del Vallès, Barcelona, at 12:00 p.m. CET on June 17, 2026, and at the same place and time, on June 18, 2026, on second call.

The Board of Directors has also resolved to approve the possibility to attend the Ordinary General Shareholders' Meeting by telematic means, by remote, simultaneous and bidirectional connection, in accordance with the provisions of the Articles of Association and the Regulations of the General Shareholders' Meeting of the Company.

The General Shareholders' Meeting will be held in accordance with the following:

Agenda

It is stated that, pursuant to the provisions of the Company's Articles of Association, only the shareholders who hold Class A shares will have the right to vote on the items included in the agenda.

Supplement to the call and filing of new resolution proposals

Pursuant to the provisions of article 519 of the Capital Companies Act (Ley de Sociedades de Capital), shareholders representing at least three percent of the Company's share capital may request the publication of a supplement to this call, including one or more items on the agenda, and filing well-founded resolution proposals on matters already included or that should be included on the agenda, provided that the new items are duly justified or accompanied, as appropriate, by a substantiated resolution proposal. This right may be exercised by means of a verifiable notice that must be received at the registered office of the Company, within five days following the publication of this notice of call or, as the case may be, of the supplement to the call. Such notice must provide evidence of the identity of the shareholders exercising such right and the number of shares they currently hold, as well as the items that, as the case may be, should be included on the agenda, and must be accompanied by all relevant documents.

Right to information

As from the date hereof, any shareholder will have the right to examine at the registered office of the Company (Parque Empresarial Can Sant Joan, Avinguda de la Generalitat, 152-158, 08174, Sant Cugat del Vallès, Barcelona), to look up on the corporate web page (www.grifols.com), and to obtain or request the immediate delivery of the following documents, free of charge:

Furthermore, the following reports will be published on the Company's corporate web page:

Additionally, pursuant to the provisions of articles 197, 272 and 520 of the Capital Companies Act (Ley de Sociedades de Capital), article 39 of the Regulations of the Board of Directors and article 9 of the Regulations of the General Shareholders' Meeting, the shareholders may request in writing that the Board of Directors, from the date of the publication of the notice of the call until the fifth day before the date when the General Shareholders' Meeting is to be held, or verbally while the meeting is being held, provide any information and clarifications that they may deem necessary, or raise any questions that they deem pertinent regarding the items included in the agenda. Furthermore, shareholders may request, within the same deadline and in the same form, any information or clarifications or raise any questions concerning the information accessible to the general public that has been provided by the Company to the National Securities Market Commission (Comisión Nacional del Mercado de Valores) since the last General Shareholders' Meeting (June 5, 2025) and concerning the auditor's report. Those shareholders (or their proxy representatives) who attend the General Shareholders' Meeting by telematic means may exercise this information right under the terms set forth in the corresponding section of this notice.

Shareholders' Electronic Forum

Pursuant to the provisions of article 539 of the Capital Companies Act (Ley de Sociedades de Capital), on occasion of the call of the General Shareholders' Meeting and until 8:30 a.m. CET of the same day it is held, the Company has enabled the Shareholders' Electronic Forum on the Company's corporate web page (www.grifols.com). The operating rules and the form that the shareholders must fill in in order to participate in said Forum are available on the Company's corporate web page.

Right to attend

All shareholders of the Company will have the right to attend the General Shareholders' Meeting, provided that their shares are registered under their name in the corresponding accounting registry at least five days prior to the day on which the General Shareholders' Meeting is to be held.

In order to exercise the right to attend, the shareholder must have the relevant attendance card issued for such purposes by the entities responsible for the accounting registry.

Any shareholder having the right to attend may be represented by another person, even if such person is not a shareholder. The representation shall be conferred on a special basis for this specific General Shareholders' Meeting, in writing or via any distance means of communication as set forth below.

Those shareholders or proxy representatives that wish to attend to the General Shareholders' Meeting by telematic means must follow the instructions set forth further below.

Right to vote and distance voting

Shareholders may cast their vote regarding the proposals included on the agenda through the following distance means of communication:

Likewise, the shareholders entitled to attend may confer their representation, specifically for this General Shareholders' Meeting, by the following distance means of communication:

The shareholders who confer their representation by means of distance communication must notify the appointed proxy representative of the representation conferred. When the representation is conferred to a Board Member and/or the Secretary and/or the Vice Secretary of the Company, such communication will be deemed to be made upon receipt by the Company of the distance delegation.

Distance delegations must be accepted by the proxy, not being able to join otherwise. For this purpose, all distance delegations in favor of individuals different than the Company's Board Members and/or Secretary and/or Vice Secretary must be printed out, signed and submitted by the proxy representatives who physically attend the General Shareholders' Meeting, together with an identity document, to the personnel in charge of the shareholders' registry on the date and place where the General Shareholders' Meeting is to be held, within the hour immediately prior to its scheduled start.

Moreover, the delegation card duly completed and signed may also be submitted by the proxy representative physically attending the Meeting, together with an identity document, to the personnel in charge of the shareholders' registry, on the date and place where the General Shareholders' Meeting is to be held, within the hour immediately preceding its scheduled start.

In order to be valid, both the vote and the distance delegation must be received by the Company at least before midnight (24:00) on the day prior to the date that the General Shareholders' Meeting is scheduled at its first call or second call, whichever is applicable.

The Company reserves the right to modify, suspend, cancel or restrict the mechanisms for electronic voting and delegation for technical or security reasons. The Company further reserves the right to request such additional identification from the shareholders as may be deemed convenient in order to ensure the identity of those attending the meeting, the authenticity of the vote or the delegation and, in general, the legal certainty of the General

Shareholders’ Meeting being held.

The Company will not be liable for damages that may be caused to shareholders due to the lack of availability and effective operation of its corporate web page and of the services or contents provided through such web page as a result of any failure, overload, line failure, connection fault or similar events not attributable to the Company that may impede the use of the electronic voting or delegation systems.

Computer applications for casting the vote and the delegation through electronic means will be operative from the day the call is published at 00:00:01 hours CET until June 17, 2026 at 23:59:59 hours CET.

Attendance to the General Shareholders' Meeting by telematic means

Notwithstanding the provisions set forth above and in accordance with article 182 of the Capital Companies Act (Ley de Sociedades de Capital) and article 16 of the Company's Articles of Association, the shareholders and their proxy representatives may attend the General Shareholders' Meeting by telematic means.

1.             Registration, accreditation and attendance:

In order to enable the proper management of the online attendance systems, the shareholder or proxy representative wishing to attend the General Shareholders' Meeting by telematic means must:

At the time of registration it is essential to provide proof of the status of shareholder, and, if appropriate, proxy representative, by attaching to the corresponding form a pdf copy of the duly signed attendance card issued by the participating entity of Sociedad de Gestión de los Sistemas de Registro, Compensación y Liquidación de Valores

(Iberclear) where the shareholder's shares are deposited.

Moreover, the shareholder that is a legal entity shall also attach to the corresponding form a pdf copy of the documents that prove the representative authorities of the natural person that represents it. In addition, the shareholder's proxy representative shall attach a copy of the document in which the representation is granted.

Any registration made outside the deadlines indicated above or which does not comply with the accreditation requirements referred to in this section (a) will not be accepted.

The Company reserves the right to request from the shareholders and/or its proxy representatives any additional proofs of identification it considers necessary to verify their status as shareholders or the sufficiency of the powers of representation granted.

2.             Exercise of the rights of intervention, information and proposal:

The shareholders or their proxy representatives who, in exercise of their rights, wish to participate at the Meeting by telematic means and, if necessary, request information or clarifications regarding the items included on the agenda, the information accessible to the general public that has been provided by the Company to the National Securities Market Commission (Comisión Nacional del Mercado de Valores) since the last General Shareholders' Meeting or the auditor's report, or make proposals as permitted by Law, must submit their requests or proposals in writing by sending an electronic communication with their intervention (or attaching their written intervention) through the Online Attendance Platform enabled on the Company's web page. These rights may be exercised from the moment the shareholders or their proxy representatives are connected to the General Shareholders' Meeting via telematic means and until the closing of the period of interventions, which will be duly indicated during the course of the General Shareholders' Meeting.

The attendee to the Meeting by telematic means who wishes to have his/her intervention expressly included in the minutes of the General Shareholders' Meeting must state this clearly and expressly within his/her written communication.

The interventions of the attendees to the Meeting by telematic means can be verbally answered during the General Shareholders' Meeting or in writing within seven days thereafter, all in accordance with the provisions of the Capital Companies Act (Ley de Sociedades de Capital).

3.             Voting:

Votes may be cast by telematic means on the proposals relating to the items included on the agenda using the form available on the Online Attendance Platform enabled for this purpose on the Company's web page (www.grifols.com) from the time of their connection as attendees via telematic means on the date of the General Shareholders' Meeting indicated in section 1.(b) above, and until the moment the voting process on the proposed resolutions is concluded during the General Shareholders' Meeting, which will be indicated in due course during the General Shareholders' Meeting.

With regard to the proposed resolutions on those matters not included on the agenda that have been presented in the legally admissible cases, those attending by telematic means may cast their vote through the form available on the Online Attendance Platform enabled for this purpose on the web page (www.grifols.com) from the moment these proposals are read out for voting and until the moment the voting process is concluded during the General Shareholders' Meeting.

The rules on the computation of votes set out in the Articles of Association and in the Regulations of the General Shareholders' Meeting shall apply to the voting by telematic means.

4.             Other issues:

The shareholders or their proxy representatives who attend the General Shareholders' Meeting by telematic means and who wish to expressly state that they are abandoning the General Shareholders' Meeting so that their vote will not be counted, must do so by sending an electronic communication through the available link enabled for this purpose on the Online Attendance Platform on the Company's web page (www.grifols.com). Once such express desire to abandon the meeting has been communicated, all subsequent actions made by telematic means will be deemed as not having been carried out.

The attendance by telematic means of the shareholder or his/her proxy representative will render void any vote or delegation previously made by any other procedure established by the Company.

It is the exclusive responsibility of the shareholder or his/her proxy representative to maintain the passwords or any identification means required to access and use the Online Attendance Platform. In the case of a legal entity, it must notify any modification or revocation of the powers held by its representative and, therefore, the Company declines any responsibility until such notification takes place.

The Company reserves the right to modify, suspend, cancel or restrict the mechanisms for the attendance to the General Shareholders' Meeting by telematic means when technical or security reasons so require or impose it. The Company will not be liable for damages that may be caused to shareholders as a result of any failure, overload, line failure, connection fault or similar events not attributable to the Company that may impede the use of the attendance systems to the General Shareholders' Meeting. Therefore, such circumstances will not constitute an illegitimate deprivation of the shareholders' rights. Should any of the circumstances envisaged in this section occur, the shareholders will be informed of this as soon as possible through the Company's web page.

The rules for attendance at the General Shareholders' Meeting by telematic means adopted by the Board of Directors are available for the shareholders consultation on the Company's web page at www.grifols.com.

Participation of a Notary at the Meeting

The Board of Directors has resolved to request the presence of a Notary Public in order to draw up the minutes of the General Shareholders' Meeting, pursuant to the provisions of article 203 of the Capital Companies Act (Ley de Sociedades de Capital).

Privacy Information

Grifols, S.A. is the data controller responsible for processing your personal data for the purpose of managing the Shareholders’ Meeting. The legal basis for this processing is the management of the shareholder relationship, Grifols’ legitimate interest, and compliance with legal obligations. The information may be shared with the service providers that support the organization of the meeting. You may exercise your rights of access, rectification, and erasure, as well as other rights detailed in the additional information. You may review the detailed data protection information in the “Privacy Notices” section of the corporate website www.grifols.com (https://www.grifols.com/en/shareholders-meeting).

The meeting will be streamed live to shareholders and/or authorized representatives, for the purpose of enabling them to follow the proceedings. The meeting will be audiovisually recorded to documenting the event. By entering the premises where the meeting is held or by making an intervention, the attendee’s image and voice may be captured for the purposes indicated, on the basis of the legitimate interest of Grifols, S.A.

Expected date of the General Shareholders' Meeting

THE SHAREHOLDERS ARE INFORMED THAT THE GENERAL SHAREHOLDERS' MEETING WILL FORESEEABLY BE HELD ON SECOND CALL ON JUNE 18, 2026 AT 12:00 HOURS CET, AT THE PLACE FIRST WRITTEN ABOVE.

Attendance cards

The shareholders are reminded that in order to exercise their right of attendance to the General Shareholders' Meeting they must have the relevant attendance card issued for such purposes by the entities responsible for the accounting registry. These attendance cards will have to detail, as applicable, the number of shares of each class (Class A or Class B shares) held by the shareholders. The entities in charge of the accounting registries may also issue to the shareholders two separate cards, that is, one for Class A shares and another for Class B shares held by each shareholder, as the case may be.

Transport

On June 18, 2026 the shareholders will have at their disposal a free shuttle service between the station of Sant Joan (Vallès line of the Catalan Railway Network – FGC) and the Company's offices where the General Shareholders' Meeting is to be held, running from 11:15 to 11:45 hours CET from the station, and from 13:15 hours CET from the Company's offices.

Barcelona, May 15, 2026 

The Secretary to the Board of Directors 

Ms. Laura de la Cruz Galán

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereto duly authorized.

Date: May 15, 2026