Mostostal Warszawa S.A.

Major Shareholding Notification • Aug 29, 2019

Acciona S.A. Avda. Europa 18. Parque Empresarial La Moraleja 28108 Alcobendas (Madrid), Spain

Mostostal Warszawa S.A. ul. Konstruktorska 12A 02-673 Warsaw, Poland

Komisja Nadzoru Finansowego (Polish Financial Supervision Authority) ul. Piekna 20 00-549 Warsaw, Poland

Acciona S.A. with its registered office in Madrid, Spain address: Avda. Europa 18. Parque Empresarial La Moraleja 28108 Alcobendas (Madrid), Spain (the "Notifying Entity"), pursuant to Article 69 Section 2 Item 2 in connection with Article 69a Section 1 Item 3 of the Polish act on public offering, the conditions governing the introduction of financial instruments to an organized trading, and on public companies of 29 July 2005 (consolidated text: Dz. U. of 2019, item 623) (the "Act on Public Offering"), hereby notifies that it has indirectly acquired 573,518 (five hundred seventy-three thousand five hundred eighteen) shares in Mostostal Warszawa S.A. with its registered office in Warsaw (the "Company") constituting 2.87% of the Company's share capital, authorizing to 573,518 (five hundred seventy-three thousand five hundred eighteen) votes at the Company's general meeting and representing 2.87% of the total number of votes at the Company's general meeting.

The indirect acquisition of the abovementioned shares in the Company results from the shares purchase transactions entered into by Acciona Construcción S.A. on 26 August 2019 (which were settled on 29 August 2019) concerning the shares in the Company covered by the subscriptions for the sale placed by the Company's shareholders in response to the 2nd stage of the tender offer to subscribe for the company announced on 2 July 2019 by Acciona Construcción S.A. pursuant to Article 74 Section 1 of the Act on Public Offering (the "Indirect Acquisition").

Prior to the Indirect Acquisition the Notifying Entity held indirectly through Corporación Acciona Infraestructuras, S.L. and Acciona Construcción S.A. (a direct subsidiary of Corporación Acciona Infraestructuras, S.L.) 11,852,870 (eleven million eight hundred fifty-two thousand eight hundred seventy) shares in the Company representing 11,852,870 (eleven million eight hundred fifty-two thousand eight hundred seventy) votes at a general meeting of the Company, accounting for 59.26% of the Company's share capital and vesting the right to exercise 59.26% of the total number of votes in the Company (Acciona Construcción S.A. holding directly the abovementioned shares in the Company).

After the Indirect Acquisition and as at the date of this notifying Entity holds indirectly 12,426,388 (twelve million four hundred twenty-six thousand three hundred eighty-eight) shares in the Company representing 12,426,388 (twelve million four hundred twenty-six thousand three hundred eighty-eight) votes at a general meeting of the Company, accounting for 62.13% of the Company's share capital and vesting the right to exercise 62.13% of the total number of votes in the Company.

Other than Acciona Construcción S.A. (holding directly the abovementioned shares in the Company) and Corporación Acciona Infraestructuras, S.L. (holding the shares in the Company indirectly through Acciona Construcción S.A.) there are no direct or indirect subsidiaries of the Notifying Entity that directly hold the shares in the Company.

The Notifying Entity is not a party to any agreements on the right to exercise the voting right attached to the Company's shares within the meaning of Article 87 Section 1 Item 3 Letter c of the Act on Public Offering.

The Notifying Entity does not hold any financial instruments which after their maturity date entitle or oblige its holder unconditionally to acquire shares, to which rights to vote are attached, already issued by the Company, referred to in Article 69b Section 1 Item 1 of the Act on Public Offering.

The Notifying Entity also does not hold any financial instruments related, directly or indirectly, to the Company's shares that give rise to any economic consequences similar to consequences of the financial instruments specified in the preceding sentence, referred to in Article 69b Section 1 Item 2 of the Act on Public Offering.

Due to the fact that the Notifying Entity does not hold any financial instruments referred to in Article 696 Section 1 Items 1 and 2 of the Act on Public Offering, the total number of votes in the Company, as well as the total percentage share in the total number of votes in the Company, referred to in Article 69 Section 4 Item 9 of the Act on Public Offering, correspond to the number of votes attached to shares of the Company and the percentage share in the total number of votes in the Company specified above.

On behalf of Acciona S.A. 27 le 7 these Name and surname

Raimundo Fernández-Cuesta Laborde

Position: Global Director Markets and Investor Relations