UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

o

Rule 13d-1(b)

o

Rule 13d-1(c)

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Rule 13d-1(d)

CUSIP No. 594918104

1.

Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only)
William H. Gates III

2.

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)

o

(b)

o

3.

SEC Use Only

4.

Citizenship or Place of Organization
United States

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
997,499,336

6.

Shared Voting Power 
–0–

7.

Sole Dispositive Power 
997,499,336

8.

Shared Dispositive Power
–0–

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
997,499,336

10.

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o

11.

Percent of Class Represented by Amount in Row (9)
9.7%

12.

Type of Reporting Person (See Instructions)
IN

Item 1.

(a)

Name of Issuer
Microsoft Corporation (the “Issuer”)

(b)

Address of Issuer’s Principal Executive Offices
One Microsoft Way, Redmond, Washington 98052

Item 2.

(a)

Name of Person Filing
William H. Gates III

(b)

Address of Principal Business Office or, if none, Residence
One Microsoft Way, Redmond, Washington 98052

(c)

Citizenship
United States of America

(d)

Title of Class of Securities
Common Stock, $0.00000625 par value per share

(e)

CUSIP Number
594918104

Item 3.

If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

o

Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b)

o

Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c)

o

Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d)

o

Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C 80a-8).

(e)

o

An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);

(f)

o

An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

(g)

o

A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h)

o

A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

o

A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)

o

Group, in accordance with §240.13d-1(b)(1)(ii)(J).

Not Applicable

Item 4.

Ownership

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

(a)

Amount beneficially owned:    

997,499,336

(b)

Percent of class:   

9.7%

(c)

Number of shares as to which the person has:

(i)

Sole power to vote or to direct the vote   

997,499,336

(ii)

Shared power to vote or to direct the vote    

–0–

(iii)

Sole power to dispose or to direct the disposition of   

997,499,336

(iv)

Shared power to dispose or to direct the disposition of   

–0–

Item 5.

Ownership of Five Percent or Less of a Class

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following   o.

Not Applicable

Item 6.

Ownership of More than Five Percent on Behalf of Another Person

Not Applicable

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person

Not Applicable

Item 8.

Identification and Classification of Members of the Group

Not Applicable

Item 9.

Notice of Dissolution of Group

Not Applicable

Item 10.

Certification

Not Applicable

February 14, 2006

Date

WILLIAM H. GATES III

By

/s/ Michael Larson

Name:

Michael Larson*

Title:

Attorney–in–fact