Sweco AB (publ) (“Sweco”) has prepared a supplementary prospectus supplementing the prospectus which was approved by the Swedish Financial Supervisory Authority (the “SFSA”) on 10 July 2015 in relation to the admittance to trading on Nasdaq Stockholm of the new class B shares in Sweco to be issued as consideration in the previous announced public offer for all the shares in Grontmij N.V. (“Grontmij”). The supplementary prospectus constitutes a part of, and shall be read together with, the prospectus.

The supplementary prospectus has been prepared in connection with that Sweco, on 17 July 2015, and Grontmij, on 3 August 2015, published their respective interim reports for the first half of the 2015 financial year (1 January 2015 – 30 June 2015).

The supplementary prospectus has been approved by the SFSA and will be available electronically at the SFSA website www.fi.se and is available at Sweco’s website www.swecogroup.com.