Genmab — Share Issue/Capital Change 2013

May 15, 2013

Capital Increase in Genmab as a Result of Employee Warrant Exercise

Company Announcement

Copenhagen, Denmark; May 15, 2013 – Genmab A/S (OMX: GEN) will increase its share capital by 339,926 shares as a consequence of the exercise of employee warrants.

The increase is effected without any preemption rights for the existing shareholders of the company or others. The shares are subscribed in cash at the following price per share of nominally DKK 1: 2,625 shares at DKK 31.75, 3,500 shares at DKK 40.41, 5,125 shares at DKK 45.24, 3,375 shares at DKK 46.74, 2,000 shares at DKK 55.85, 1,300 shares at DKK 66.60, 500 shares at DKK 67.50, 3,750 shares at DKK 68.65, 1,500 shares at DKK 77, 127,950 shares at DKK 86, 14,688 shares at DKK 101, 167,363 shares at DKK 114, 2,250 shares at DKK 116 and 4,000 shares at DKK 129.75. Proceeds to the company are approx. DKK 33.6 million. The increase corresponds to approx. 0.67 % of the company's share capital.

The increase includes the exercise of 115,000 warrants by President & CEO Jan van de Winkel. This will take Jan van de Winkel's personal holding of shares in Genmab A/S from 330,000 to 445,000 shares.

The new shares are ordinary shares without any special rights and are freely transferable negotiable instruments. The new shares give rights to dividends and other rights in relation to the company as of subscription, i.e. inter alia full rights to dividends for the financial year 2013. The new shares will be listed on NASDAQ OMX Copenhagen after registration with the Danish Business Authority. Genmab A/S' current share capital amounts to DKK 50,712,892 and will after the capital increase be DKK 51,052,818. The capital increase is expected to be finalized shortly.

About Genmab A/S

Genmab is a publicly traded, international biotechnology company specializing in the creation and development of differentiated human antibody therapeutics for the treatment of cancer. Founded in 1999, the company's first marketed antibody, ofatumumab (Arzerra®), was approved to treat chronic lymphocytic leukemia in patients who are refractory to fludarabine and alemtuzumab after less than eight years in development. Genmab's validated and next generation antibody technologies are expected to provide a steady stream of future product candidates. Partnering of innovative product candidates and technologies is a key focus of Genmab's strategy and the company has alliances with top tier pharmaceutical and biotechnology companies. For more information visit www.genmab.com.

Contact:

Rachel Curtis Gravesen, Senior Vice President, Investor Relations & Communications T: +45 33 44 77 20; M: +45 25 12 62 60; E: r.gravesen@genmab.com

This Company Announcement contains forward looking statements. The words "believe", "expect", "anticipate", "intend" and "plan" and similar expressions identify forward looking statements. Actual results or performance may differ materially from any future results or performance expressed or implied by such statements. The important factors that could cause our actual results or performance to differ materially include, among others, risks associated with pre-clinical and clinical development of products, uncertainties related to the outcome and conduct of clinical trials including unforeseen safety issues, uncertainties related to product manufacturing, the lack of market acceptance of our products, our inability to manage growth, the competitive environment in relation to our business area and markets, our inability to attract and retain suitably qualified personnel, the unenforceability or lack of protection of our patents and proprietary rights, our relationships with affiliated entities, changes and developments in technology which may render our products obsolete, and other factors. For a further discussion of these risks, please refer to the risk management sections in Genmab's most recent financial reports, which are available on www.genmab.com. Genmab does not undertake any obligation to update or revise forward looking statements in this Company Announcement nor to confirm such statements in relation to actual results, unless required by law.

Genmab A/S and its subsidiaries own the following trademarks: Genmab® ; the Y-shaped Genmab logo® ; the DuoBody™ logo; HuMax® ; HuMax-CD20® ; DuoBody® , HexaBodyTM and UniBody® . Arzerra® is a trademark of GlaxoSmithKline.

Genmab A/S Tel: +45 7020 2728 Company Announcement no. 21 Bredgade 34E Fax: +45 7020 2729 Page 1/1 1260 Copenhagen K, Denmark www.genmab.com CVR no. 2102 3884