Report Pursuant to Section 28a of the Danish Securities Trading Act

Copenhagen, Denmark; May 30, 2008 - Pursuant to Section 28a of the Danish       
Securities Trading Act, Genmab A/S (OMX: GEN) shall make public information on  
transactions by managerial employees and their related parties involving Genmab 
shares and related instruments, as follows:                                     

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| Name           | Hans Henrik Munch-Jensen                                    |
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| Reason         | Board Member                                                |
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| Issuer         | Genmab A/S                                                  |
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| ID code/ ISIN  | DK 0010272202                                               |
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| Description    | Shares                                                      |
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| Transaction    | Purchase                                                    |
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| Trading date   | May 30, 2008                                                |
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| Market         | OMX The Nordic Exchange Copenhagen A/S                      |
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| Number         | 583                                                         |
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| Market value   | DKK 149,539.50                                              |
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About Genmab A/S                                                                
Genmab is a leading international biotechnology company focused on developing   
fully human antibody therapeutics for unmet medical needs.  Using cutting-edge  
antibody technology, Genmab's world class discovery, development and            
manufacturing teams have created and developed an extensive pipeline of products
for potential treatment of a variety of diseases including cancer and autoimmune
disorders.  As Genmab advances towards a commercial future, we remain committed 
to our primary goal of improving 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 press 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. Genmab is 
not under an obligation to up-date statements regarding the future following the
publication of this release; nor to confirm such statements in relation to      
actual results, unless this is required by law.                                 

Genmab(R); the Y-shaped Genmab logo(R); HuMax(R); HuMax-CD4(R); HuMax-CD20(R);  
HuMax-EGFr(TM); HuMax-IL8(TM); HuMax-TAC(TM); HuMax-HepC(TM); HuMax-CD38(TM);   
HuMax-CD32b(TM) and UniBody(R) are all trademarks of Genmab A/S.                

Contact: Helle Husted, Sr. Director, Investor Relations, T: +45 33 44 77 30, M: 
+45 25 27 47 13, E: hth@genmab.com                                              
                                                                                
Stock Exchange Release no. 26/2008                                              

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