SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


                                    FORM 6-K


                        Report of Foreign Private Issuer


                       Pursuant to Rule 13a-16 or 15d-16
                     of the Securities Exchange Act of 1934


                         For the month of August, 2007

                              RYANAIR HOLDINGS PLC
                (Translation of registrant's name into English)

                     c/o Ryanair Ltd Corporate Head Office
                                 Dublin Airport
                             County Dublin Ireland
                    (Address of principal executive offices)


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.....


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 ..... No ..X..


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



               RYANAIR ACQUIRES A FURTHER 4% STAKE IN AER LINGUS

Ryanair, today (Monday, 20th August 2007) confirmed that it had acquired a
further 4% stake in Aer Lingus, taking its holding in Aer Lingus to over 29.4%.
These new shares were acquired at or less than EUR2.45 per share which lowers
the average cost of Ryanair's shares in Aer Lingus.

Ends.                             Monday, 20th August 2007

For reference:
Peter Sherrard - Ryanair          Pauline McAlester - Murray Consultants

Tel: +353-1-8121228               Tel: +353-1-4980300



                                   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, hereunto duly authorized.

                                    RYANAIR HOLDINGS PLC


Date:  20 August, 2007

                                    By:___/s/ James Callaghan____

                                    James Callaghan
                                    Company Secretary & Finance Director