Exhibit 10.4

FIRST LEASE AMENDMENT

THIS FIRST LEASE AMENDMENT (the "Amendment") is executed this 12th day of April, 2000 (the "Execution Date"), effective as of the 1st day of March,
2000 (the "Effective Date"), by and between DUKE-WEEKS REALTY LIMITED PARTNERSHIP, an Indiana limited partnership ("Landlord"), and GAIAM, INC., a Colorado corporation ("Tenant").

W I T N E S S E T H:

WHEREAS, Landlord and Tenant entered into a certain lease dated December 16, 1999 (the "Lease"), whereby Tenant leased from Landlord certain premises
consisting of approximately 208,120 square feet of space (the "Leased Premises") located in a building commonly known as World Park at Union Centre, Building No. 8, located at 9107 Meridian
Way, Cincinnati, Ohio 45069; and

WHEREAS,
Tenant requested that Landlord make additional tenant finish improvements in the Leased Premises, and Landlord agreed to make such additional tenant finish improvements and to
amortize the cost of such tenant finish improvements into the rent; and

WHEREAS,
Landlord and Tenant desire to amend the Minimum Annual Rent and Monthly Rental Installments to include the costs of such tenant finish improvements; and

WHEREAS,
Landlord and Tenant desire to extend the Lease Term; and

WHEREAS,
Landlord and Tenant desire to amend certain provisions of the Lease to reflect such amortization, extension, changes and additions to the Lease;

NOW,
THEREFORE, in consideration of the foregoing premises, the mutual covenants herein contained and each act performed hereunder by the parties, Landlord and Tenant hereby agree that
the Lease is amended as follows:

1.Incorporation of Recitals.The above recitals are hereby incorporated into this Amendment as if fully set
forth herein.

2.Extension of Lease Term.The Lease Term is hereby extended through March 31, 2006.

3.Amendment of Section 1.01. Basic Lease Provisions and Definitions.Commencing on the Effective Date, Section 1.01of the Lease is hereby amended by deleting subsections D, E and G and substituting the following in lieu thereof:

March 1, 2000March 31, 2000

$0.00 (1 month)*April 1, 2000February 28, 2001

$528,935.00 (11 months)*March 1, 2001February 28, 2002

$769,632.00 per yearMarch 1, 2002February 28, 2003

$769,632.00 per yearMarch 1, 2003February 29, 2004

$769,632.00 per yearMarch 1, 2004February 28, 2005

$769,632.00 per yearMarch 1, 2005February 28, 2006

$769,632.00 per yearMarch 1, 2006March 31, 2006

$64,136.00 (1 month);




March 1, 2000March 31, 2000

$0.00 (1 month)*April 1, 2000February, 28 2001

$48,085.00 per monthMarch 1, 2001March 31, 2006

$64,136.00 per month;


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IN
WITNESS WHEREOF, the parties have caused this Amendment to be executed on the Execution Date, effective as of the Effective Date.

|WITNESSES:                    |  | LANDLORD:                                                            
|----------------------------- |  | ---------------------------------------------------------------------
|/s/STEVE DENISONSteve Denison |  | DUKE-WEEKS REALTY LIMITED PARTNERSHIP, an Indiana limited partnership
|/s/ANGELA ARBINOAngela Arbino |  | By:                                                                  
|                              |  | By:                                                                  
|WITNESSES:                    |  | TENANT:                                                              
|/s/JANET MATHEWSJanet Mathews |  | GAIAM, INC., a Colorado corporation                                  
|/s/CARRIE ULRICH              |  | By:                                                                  
|Carrie Ulrich                 |  | Printed:                                                             
|                              |  | Title:                                                               



|STATE OF OHIO      |  | )     |  | 
|------------------ |  | ----- |  | 
|                   |  | ) SS: |  | 
|COUNTY OF HAMILTON |  | )     |  | 

Before
me, a Notary Public in and for said County and State, personally appeared Robert D. Fessler, by me known and by me know to be the Senior Vice President of Duke-Weeks
Realty Corporation, an Indiana corporation, the general partner of Duke-Weeks Realty Limited Partnership, an Indiana limited partnership, who acknowledged and execution of the foregoing
"First Lease Amendment" on behalf of said partnership.

WITNESS
my hand Notarial Seal this 12th day of April, 2000.

|(NOTARY SEAL) |  | /s/ROSE ANDRIACCONotary Public
Rose Andriacco
Notary Public, State of Ohio
My Commission Expires March 8, 2005
My County of Residence: Clermont.
|------------- |  | ------------------------------------------------------------------------------------------------------------------------------------------------

|STATE OF COLORADO |  | )     |  | 
|----------------- |  | ----- |  | 
|                  |  | ) SS: |  | 
|COUNTY OF BOULDER |  | )     |  | 

Before
me, a Notary Public in and for said County and State, personally appeared Mark Lipien, by me known and by me known to be the Vice President of Gaiam, Inc., a Colorado
corporation, who acknowledged the execution of the foregoing "First Lease Amendment" on behalf of said corporation.

WITNESS
my hand Notarial Seal this 8th day of March, 2000.

| |  | /s/CHELLI L. SMITHNotary Public
Chelli L. Smith
Notary Public, State of Colorado
My Commission Expires April 12, 2000
My County of Residence: Boulder.
| |  | ------------------------------------------------------------------------------------------------------------------------------------------------------



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