April 6, 2012



United States Securities and Exchange Commission
Division of Corporate Finance
100 F Street, N.E.
Washington, D.C. 20549
Attention:   Mark P. Shuman, Branch Chief
 

 
Re:
Network-1 Security Solutions, Inc.
Post-Effective Amendment No. 5 to Form S-1
Filed March 23, 2012
File No. 333-143710                                                   
 

Dear Mr. Shuman:

With respect to the Staff's comment letter, dated April 2, 2012, Network-1 Security Solutions, Inc. (the "Company") acknowledges the following:
 
·  
should the Commission or the staff, acting pursuant to delegated authority, declare the filing effective, it does not foreclose the Commission from taking any action with respect to the filing;
 
·  
the action of the Commission or the staff, acting pursuant to delegated authority, in declaring the filing effective, does not relieve the Company from its full responsibility for the adequacy and accuracy of the disclosure in the filing; and
 
·  
the Company may not assert staff comments and the declaration of effectiveness as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.
 
 
 
Network-1 Security Solutions, Inc.
 

 
By:     /s/ Corey M. Horowitz                                    
Corey M. Horowitz, Chairman
and Chief Executive Officer