arGEN-X Appoints Petercam NV as Liquidity Provider to Facilitate Trading on Euronext Brussels

Breda, the Netherlands / Ghent, Belgium– arGEN-X N.V. (Euronext Brussels: ARGX), a clinical-stage biopharmaceutical company focused on creating and developing differentiated therapeutic antibodies for the treatment of cancer and severe autoimmune diseases, announced today that it has appointed Petercam NV as a liquidity provider for the Company’s common shares currently listed on Euronext Brussels under the trading symbol ARGX.

A liquidity provider facilitates the buying and selling of shares in order to narrow the difference between the bid and ask prices of a traded security. The liquidity provider’s goal is to improve the marketability of the shares, enabling shareholders to more efficiently trade in the Company’s common stock so that in normal circumstances adequate liquidity can be maintained. The agreement between Petercam NV and the Company is compliant with Euronext Rule Book for liquidity providers. The agreement is effective as of 18 September 2014.

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About Petercam NV

Petercam is a leading independent investment firm specializing in private banking, institutional asset management and investment banking (corporate finance and financial intermediation).

As a financial advisor, it offers the highest standards in the execution of corporate financing projects. The services range from M&A, capital market transactions and fairness opinions, both in Belgium and internationally thanks to the exclusive M&A alliance with houses in more than 40 countries.

Thanks to its expertise in research based equity brokerage, Petercam has developed long lasting relationships with institutional clients and is respected for its placement power. Drawing on a team of analysts, sales and traders based in Brussels, Amsterdam and New York, it acts as a leading broker in Benelux stocks and institutional bonds.

As at 31 December 2013, Petercam employed 421 people and managed assets totaling approximately 14 billion euro for private and institutional clients, corporates and public institutions.