THIRD AMENDMENT TO LEASE DATED MAY 9, 2011



 Exhibit 10.2 
 THIRD AMENDMENT TO LEASE 
 This THIRD AMENDMENT TO LEASE (this
“Amendment”) between B&N 141-302, LLC, a Washington limited liability company (“Landlord”) and SEATTLE GENETICS, INC., a Delaware corporation (“Tenant”). 

Tenant, and Landlord, as successor owner to WCM 132-302, LLC, are parties to that certain Lease dated December 1, 2000, as amended
by that certain First Amendment to Lease dated May 28, 2003 and that certain Second Amendment to Lease dated July 1, 2008 (as amended, the “Lease”). Capitalized terms which are not defined herein shall have the meanings set forth
in the Lease. 
 WCM HIGHLANDS II, LLC, an affiliate of Landlord, and Tenant are in the process of entering
into a lease for the building located at 21717 30th Drive
SE (the “Ridgepoint Lease”). In order to induce the landlord to provide a $[***] allowance in the Ridgepoint Lease, Tenant has agreed to cancel the termination options contained in the Lease. 

Landlord and Tenant agree as follows: 
 1. CANCELLATION OF TERMINATION RIGHTS. In consideration of the inclusion of a $[***]allowance for lobby improvements in the Ridgepoint Lease, Tenant’s termination rights set forth in
Section 7 of the Second Amendment to the Lease are hereby cancelled. 
 2. EFFECTIVE DATE. This Amendment shall take
effect upon the mutual execution and delivery of the Ridgepoint Lease. 
 3. NO OTHER AMENDMENTS. Except as modified by
this Amendment, the First and Second Amendment, the Lease remains in full force and effect and has not been modified or amended. 
  

					
	DATED: May 9, 2011	 	Landlord:	 	B&N 131-302, LLC,
		 		 	a Washington limited liability company
			
		 		 	By: Washington Capital Management, Inc.
		 		 	Its: Manager

  

					
	 	 	 	 	      By: /s/ Cory A.
Carlson                                        
                          
		 		 	            Cory A. Carlson, President

  

					
	 	 	Tenant:	 	SEATTLE GENETICS, INC.,
		 		 	a Delaware corporation
			
		 		 	By: /s/ Clay B. Siegall,
PhD                                         
                         
		 		 	Its: President &
CEO                                         
                                    

 Confidential treatment has been requested for portions of this exhibit. The copy filed herewith omits the

 information subject to the confidentiality request. Omissions are designated as [***]. A complete version of 

this exhibit has been filed separately with the Securities and Exchange Commission. 








			
	STATE OF WASHINGTON	 	        )
		 	        ) ss.
	COUNTY OF KING	 	        )

 I certify that I know or have satisfactory evidence that Patrick S. Malley is the person who appeared
before me, and said person acknowledged that he/she signed this instrument, on oath stated that he/she was authorized to execute the instrument and acknowledged it as Senior Vice President of Washington Capital Management, Inc., Manager of B&N
141-302, LLC, a Washington limited liability company to be the free and voluntary act of such party for the uses and purposes mentioned in this instrument. 
  

					
	DATED: May 9, 2011.	 	 	 	 
		 		 	/s/ Jennifer Ourada
		 		 	  
 (Signature of Notary
Public)

			
		 		 	Jennifer Ourada
		 		 	  
 (Printed Name of Notary
Public)

			
		 		 	My Appointment expires 8-20-14


			
	STATE OF WASHINGTON	 	        )
		 	        ) ss.
	COUNTY OF KING	 	        )

 I certify that I know or have satisfactory evidence that Todd Simpson is the person who appeared before
me, and said person acknowledged that he/she signed this instrument, on oath stated that he/she was authorized to execute the instrument and acknowledged it as CFO of SEATTLE GENETICS, INC., a Delaware corporation to be the free and voluntary act of
such party for the uses and purposes mentioned in this instrument. 
  

					
	DATED: May 9, 2011.	 	  	 	 
		 		 	/s/ Amy L. Olofson
		 		 	  
 (Signature of Notary
Public)

			
		 		 	Amy L. Olofson
		 		 	  
 (Printed Name of Notary
Public)

			
		 		 	My Appointment expires 10-9-14