Supplement to the message no. 4/2010 – Management Board Report justifying the merger

In connection with the planned merger of Polimex Mostostal S.A. with Energomonta#-Północ S.A., Naftobudowa S.A., Naftoremont Sp. z o.o., Zakłady RemontoweEnergetyki Kraków Sp. z o.o., Zakłady Remontowe Energetyki Lublin S.A., EPERybnikSp. z o.o., ECeRemont Sp. z o.o. and to supplement the message no. 4/2010,the Management Board of Polimex-Mostostal S.A. informs about the followingconclusions resulting from the analyses of the effects of synergies carried out incooperation with the Company’s adviser – AT KEARNEY that were the consequenceof: integration of support function, optimization of purchase costs, integration ofoperational activity and ownership changes:

1/ target annual value of synergy is planned to be achieved in the third year followingthe merger and should amount to 50.9 million zlotys;

2/ NPV (net present value of synergy) for the period 2010-2020 should amount to over250 million zlotys;

In addition the integration of the companies should lead to other positive changeswhich have not been included in the abovementioned valuation – this relates, amongother things, to:1/ making the Group management system more efficient,

2/ increasing the capability of complex realisation of large modernisation andinvestment projects,

3/ more effective use of human, intellectual and material resources,

4/ increased Group transparency for investors and analysts.

Legal grounds: § 5 (1) (13) as related to § 19 (2) (2) and §19 (3) of the Ordinance of the Ministerof Finance dated 19 February 2009 on current and periodical informationprovided by issuers of securities and terms of deeming information required bythe regulations of a non-Member State equivalent (Journal of Laws of 2009, no.33, item 259 as amended).