Declaratory Relief Complaint for Patent Infringement under Patent based on Manufacture, Marketing and Sale of Arzerra

Copenhagen, Denmark; March 25, 2010 - Genmab A/S (OMX: GEN) announced today
that on March 23, 2010 Genentech, Inc. and Biogen Idec, Inc. filed a
declaratory relief complaint at the US District Court, Southern District of
California against Genmab's collaboration partner GlaxoSmithKline (GSK) for
patent infringement under US patent No 7,682,612 based on GSK's manufacture,
marketing and sale of Arzerra™ in the United States for the treatment of
fludarabine and alemtuzumab refractory chronic lymphocytic leukemia (CLL). 

US patent No 7,682,612 was issued to Genentech, Inc. and Biogen Idec, Inc. on
March 23, 2010 and contains a claim to a method of treating CLL with anti-CD20
antibodies, wherein the method does not comprise treatment with radiolabeled
anti-CD20 antibodies. 

Genmab will in collaboration with GSK assess and analyze the claims under the
initiated legal action and determine the appropriate action in response to the
complaint. 

About Genmab A/S
Genmab is a leading international biotechnology company focused on developing
fully human antibody therapeutics for the potential treatment of cancer.
Genmab's world class discovery and development teams are using cutting-edge
technology to create and develop products to address unmet medical needs.  Our
primary goal is to improve the lives of patients who are in urgent need of new
treatment options. For more information on Genmab's products and technology,
visit www.genmab.com. 

This Stock Exchange Release 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
product discovery and development, 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
section “Risk Management” in Genmab's Annual Report, which is available on
www.genmab.com.  Genmab does not undertake any obligation to update or revise
forward looking statements in this Stock Exchange Release nor to confirm such
statements in relation to actual results, unless required by law. 

Genmab®; the Y-shaped Genmab logo®; HuMax®; HuMax-CD20®; HuMax-EGFr™;
HuMax-IL8™; HuMax-TAC™; HuMax-HepC™; HuMax-CD38™; HuMax-CD32b™; HuMax-TF™;
HuMax-Her2™; HuMax-VEGF™, HuMax-Wnt and UniBody® are all trademarks of Genmab
A/S. Arzerra™ is a trademark of GlaxoSmithKline. 


Contact:		Helle Husted, Vice President, Investor Relations
T: +45 33 44 77 30; M: +45 25 27 47 13; E: h.husted@genmab.com


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Stock Exchange Release no 10/2010