EX-99.A 2 ex99-a.htm JOINT FILING AGREEMENT DATED JULY 13, 2009 ex99-a.htm
Exhibit A
 
JOINT FILING AGREEMENT
 
The undersigned hereby consent to the joint filing by any of them of a Statement on Schedule 13D and any amendments thereto, whether heretofore or hereafter filed, relating to the securities of iBasis, Inc., and hereby affirm that this Schedule 13D is being filed on behalf of each of the undersigned.

 
Dated: July 13, 2009
 
 
KONINKLIJKE KPN N.V.,  
       
 
By:
/s/ Eric Hageman  
    Name:  Eric Hageman   
    Title:  Executive Vice President Finance & Attorney-in-Fact  
       
 
 
 
  KPN B.V.,  
     
   by: KONINKLIJKE KPN N.V.,  
its sole director  
       
  by    
 
 
 /s/ Eric Hageman  
    Name:  Eric Hageman   
    Title:  Executive Vice President Finance & Attorney-in-Fact  
       
 
 
 
CELTIC ICS INC.,  
       
   by    
 
 
 /s/ Eric Hageman  
    Name:  Eric Hageman   
    Title:  President