UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

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

For the month September 2013

(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 o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b) (1):

Yes o No x

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b) (7):

Yes o No x

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes o No x

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-                  .                              .

Grifols, S.A.

TABLE OF CONTENTS

Item	Sequential Page Number
1. Relevant Event, dated September 18, 2013.	3

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Grifols, S.A.
Parc Empresarial Can Sant Joan
Av. de la Generalitat, 152-158
08174 Sant Cugat_del Vallès
Barcelona - ESPANA
Tel. +34 935 710 500
www.grifols.com

RELEVANT EVENT

Pursuant to the provisions of article 82 of the Spanish Securities Market Act (Ley del Mercado de Valores), GRIFOLS, S.A. (the “Company) informs that the Spanish Agency for Drugs and Health products has authorized Araclon Biotech S.L., a company majority owned by Grifols, to start phase I of a clinical trial for assessing the tolerance and safety of the ABvac40 vaccine for patients with mild or moderate Alzheimer’s disease.

In Barcelona, on this 18th September 2013

Raimon Grifols Roura

Secretary to the Board of Directors

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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.

	Grifols, S.A.
	By:	/s/ David I. Bell
		Name:	David I. Bell
		Title:	Authorized Signatory
Date: September 18, 2013

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