SC 13D/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 6)*

Berkshire Hathaway Inc.

(Name of Issuer)

Class B common stock, $0.0033 Par Value

(Title of Class of Securities)

084670702

(CUSIP Number)

Matthew S. Topham, Esq.
K&L Gates LLP
925 Fourth Avenue, Suite 2900 Seattle, Washington  98104 (206) 623-7580 Laurie Smiley, Esq. Arian Colachis, Esq. 2365 Carillon Point Kirkland, WA  98033 (425) 889-7900

(Name, Address and Telephone Number of Persons Authorized to
Receive Notices and Communications)

March 1, 2010

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No.   084670702
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Cascade Investment, L.L.C.
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			o
		(b)			ý
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) WC
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)    o
	6.	Citizenship or Place of Organization State of Washington
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 6,075,000(1)
			8.	Shared Voting Power -0-
			9.	Sole Dispositive Power 6,075,000(1)
			10.	Shared Dispositive Power -0-
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 6,075,000(1)
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)   o
	13.	Percent of Class Represented by Amount in Row (11) .7%
	14.	Type of Reporting Person (See Instructions) OO

(1)Cascade Investment, L.L.C. (“Cascade”) beneficially owns 4,050 shares of Berkshire Hathaway Inc. (the “Issuer”) Class A common stock (“Class A Shares”).  All Class A Shares held by Cascade may be deemed to be beneficially owned by William H. Gates III as the sole member of Cascade.  Each Class A Share is convertible, at the option of the holder, into fifteen hundred shares of the Issuer’s Class B common stock (“Class B Shares”).  The number of Class B Shares shown above assumes the conversion of the 4,050 Class A Shares beneficially owned by Cascade into 6,075,000 Class B Shares.

1

CUSIP No.   084670702
	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)			ý
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) WC
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)    o
	6.	Citizenship or Place of Organization United States of America
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 6,525,000(1)
			8.	Shared Voting Power 77,253,900 (2)
			9.	Sole Dispositive Power 6,525,000(1)
			10.	Shared Dispositive Power 77,253,900(2)
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 83,778,900(1) (2)
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)   o
	13.	Percent of Class Represented by Amount in Row (11) 10.2%
	14.	Type of Reporting Person (See Instructions) IN

(1)William H. Gates III beneficially owns 300 shares of Berkshire Hathaway Inc. (the “Issuer”) Class A common stock (“Class A Shares”) directly and an additional 4,050 Class A Shares through Cascade Investment, L.L.C. (“Cascade”), a limited liability company solely owned by Mr. Gates.  Each Class A Share is convertible, at the option of the holder, into fifteen hundred shares of the Issuer’s Class B common stock (“Class B Shares”).  The number of Class B Shares shown above assumes the conversion of the 300 Class A Shares held directly by Mr. Gates into 450,000 Class B Shares and the conversion of the 4,050 Class A Shares held by Cascade into 6,075,000 Class B Shares.

(2)Bill & Melinda Gates Foundation Trust (the “Trust”) beneficially owns 77,253,900 shares of the Issuer’s Class B Shares.  For purposes of Rule 13d-3 under the Securities Exchange Act of 1934, as amended, all Class B Shares beneficially owned by the Trust may be deemed to be beneficially owned by William H. Gates III and Melinda French Gates, as Co-Trustees of the Trust.

2

CUSIP No.   084670702
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Bill & Melinda Gates Foundation Trust
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			o
		(b)			ý
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) OO
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)    o
	6.	Citizenship or Place of Organization State of Washington
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power -0-
			8.	Shared Voting Power 77,253,900(1)
			9.	Sole Dispositive Power -0-
			10.	Shared Dispositive Power 77,253,900 (1)
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 77,253,900 (1)
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)   o
	13.	Percent of Class Represented by Amount in Row (11) 9.5%
	14.	Type of Reporting Person (See Instructions) OO

(1)For purposes of Rule 13d-3 under the Securities Exchange Act of 1934, as amended, all Class B common stock beneficially owned by Bill & Melinda Gates Foundation Trust (the “Trust”) may be deemed to be beneficially owned by William H. Gates III and Melinda French Gates, as Co-Trustees of the Trust.

3

CUSIP No.   084670702
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Melinda French Gates
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			o
		(b)			ý
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) OO
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)    o
	6.	Citizenship or Place of Organization United States of America
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power -0-
			8.	Shared Voting Power 77,253,900 (1)
			9.	Sole Dispositive Power -0-
			10.	Shared Dispositive Power 77,253,900 (1)
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 77,253,900 (1)
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)   o
	13.	Percent of Class Represented by Amount in Row (11) 9.5%
	14.	Type of Reporting Person (See Instructions) IN

(1)Bill & Melinda Gates Foundation Trust (the “Trust”) beneficially owns 77,253,900shares of Berkshire Hathaway Inc. Class B common stock (“Class B Shares”).  For purposes of Rule 13d-3 under the Securities Exchange Act of 1934, as amended, all Class B Shares beneficially owned by the Trust may be deemed to be beneficially owned by William H. Gates III and Melinda French Gates, as Co-Trustees of the Trust.

4

EXPLANATORY STATEMENT

This Amendment No. 6 to Schedule 13D (“Amendment”) relates to the Class B common stock, $0.0033 Par Value (“Class B Shares”) of Berkshire Hathaway Inc. (the “Issuer”).  This Amendment is being filed jointly by Cascade Investment, L.L.C. (“Cascade”), Bill & Melinda Gates Foundation Trust (the “Trust”), William H. Gates III and Melinda French Gates (collectively, the “Reporting Persons”) to amend and supplement the Items set forth below of the Reporting Persons’ Schedule 13D previously filed with the Securities and Exchange Commission on August 24, 2006, as amended on July 17, 2007, March 20, 2008, July 3, 2008, March 6, 2009 and July 2, 2009.  Neither the present filing nor anything contained herein shall be construed as an admission that the Reporting Persons constitute a “group” for any purpose and the Reporting Persons expressly disclaim membership in a group.

Item 5.          Interest in Securities of the Issuer

(a)  See items 11 and 13 of the cover pages to this Schedule 13D for the aggregate number and percentage of Class B Shares beneficially owned by each of the Reporting Persons.

(b)  See items 7 through 10 of the cover pages to this Schedule 13D for the number of Class B Shares beneficially owned by each of the Reporting Persons as to which there is sole power to vote or to direct the vote, shared power to vote or to direct the vote, and sole or shared power to dispose or to direct the disposition.

(c)  During the past sixty days, the Trust sold 1,187,830 Class B Shares, as set forth in Exhibit 99.1 hereto, pursuant to the Trust’s Rule 10b5-1(c)(1) sales plan, 11,330 of which were sold prior to the 50-for-1 split of the Class B Shares effective January 21, 2010.  The sales were made to facilitate compliance with federal excise tax rules limiting excess business holdings by private foundations.

(d)  None.

(e)  Not applicable.

Item 7.         Material to be Filed as Exhibits

Exhibit 99.1      Transactions during the past sixty days

5

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date:   March 2, 2010	CASCADE INVESTMENT, L.L.C.(1)
	By:	*
		Name:		Alan Heuberger(2)
		Title:		Attorney-in-fact for Michael Larson,
				Business Manager
	BILL & MELINDA GATES FOUNDATION TRUST(1)
	By:	*
		Name:		Alan Heuberger (3)
		Title:		Attorney-in-fact for each of the Co- Trustees, William H. Gates III and Melinda French Gates
	WILLIAM H. GATES III(1)
	By:	*
		Name:		Alan Heuberger(3)(4)
		Title:		Attorney-in-fact
	MELINDA FRENCH GATES(1)
	By:	*
		Name:		Alan Heuberger (3)
		Title:		Attorney-in-fact
	*By:		/s/Alan Heuberger
			Alan Heuberger

(1)This Amendment is being filed jointly by the Reporting Persons pursuant to the Joint Filing Agreement dated August 24, 2006 and included with the signature page to the Reporting Persons’ Schedule 13D with respect to the Issuer filed on August 24, 2006, SEC File No. 005-55113, and incorporated by reference herein.

(2)Duly authorized under Special Limited Power of Attorney appointing Alan Heuberger attorney-in-fact, dated August 12, 2008, by and on behalf of Michael Larson, and attached as Exhibit 99.1 to Amendment No. 1 to Cascade’s Schedule 13D with respect to Otter Tail Corporation filed on April 15, 2009, SEC File No. 005-06638 and incorporated by reference herein.

(3)Duly authorized under Special Limited Power of Attorney appointing Alan Heuberger attorney-in-fact, dated August 12, 2008, by and on behalf of William H. Gates III and Melinda French Gates as Co-Trustees, and attached as Exhibit 99.5 to Cascade’s Schedule 13D with respect to Grupo Televisa, S.A.B. filed on May 7, 2009, SEC File No. 005-60431 and incorporated by reference herein.

(4)Duly authorized under Special Limited Power of Attorney appointing Alan Heuberger attorney-in-fact, dated August 12, 2008, by and on behalf of William H. Gates III, and attached as Exhibit 99.2 to Amendment No. 1 to Cascade’s Schedule 13D with respect to Otter Tail Corporation filed on April 15, 2009, SEC File No. 005-06638 and incorporated by reference herein.

6

EX-99.1

Exhibit 99.1

The table below specifies the date, quantity, weighted-average price, and, where applicable, the range of price per share of Class B common stock of Berkshire Hathaway Inc. (the “Issuer”) sold by Bill & Melinda Gates Foundation Trust during the past sixty days.  On January 21, 2010, the Issuer’s Class B common stock split 50-for-1, as reflected in the chart below.  All of the transactions were affected on the New York Stock Exchange or through Electronic Communication Networks.

Trade Date	Quantity Sold	Weighted-Average Price Per Share Sold ($)	Range of Price Paid ($)
3/1/2010	28,000	79.7256	79.38 - 80.30
3/1/2010	16,900	80.9615	80.44 - 81.40
3/1/2010	15,100	81.6832	81.44 - 81.94
2/26/2010	41,400	79.6166	79.25 - 80.13
2/25/2010	36,384	79.1721	78.96 - 79.40
2/24/2010	40,000	79.6386	79.25 - 79.86
2/23/2010	35,000	79.7517	79.02 - 80.00
2/22/2010	32,000	79.7315	79.06 - 80.05
2/19/2010	9,000	77.7033	77.55 - 77.90
2/19/2010	27,500	76.9355	76.54 - 77.53
2/19/2010	29,500	78.8865	78.55 - 79.32
2/18/2010	46,000	76.3184	76.08 - 76.70
2/17/2010	27,500	76.0629	75.85 - 76.35
2/16/2010	20,000	75.9490	75.79 - 76.14
2/12/2010	11,500	77.5308	77.30 - 77.79
2/12/2010	81,500	76.9442	76.30 - 77.28
2/11/2010	28,500	76.5139	76.30 - 76.79
2/11/2010	30,000	75.7708	75.28 - 76.25
2/11/2010	48,500	74.5939	74.24 - 75.18
2/10/2010	21,802	74.4753	74.40 - 74.55
2/9/2010	40,100	74.4063	74.19 - 74.68
2/8/2010	19,000	74.2251	74.03 - 74.46
2/8/2010	31,000	73.7198	73.03 - 74.02
2/5/2010	7,500	73.1929	72.90 - 73.54
2/5/2010	42,500	72.3260	71.77 - 72.74
2/4/2010	10,020	73.3678	73.25 - 73.53
2/4/2010	22,800	72.4381	72.23 -72.75
2/3/2010	23,000	74.5142	74.22 - 75.11
2/2/2010	35,494	75.6346	75.09 - 76.05
2/1/2010	2,700	76.5426	76.30 - 76.70
2/1/2010	2,800	77.8124	77.70 - 78.00
2/1/2010	6,500	75.0385	74.70 - 75.34
1/29/2010	1,000	77.7000
1/29/2010	8,000	75.8663	75.50 - 76.45
1/29/2010	16,000	75.0738	74.40 - 75.39
1/29/2010	19,000	76.8295	76.51 - 77.15
1/28/2010	7,000	73.9357	73.90 - 73.97
1/28/2010	27,000	73.1922	72.88 - 73.85
1/28/2010	35,000	72.4018	71.85 - 72.80
1/27/2010	1,000	73.5500
1/27/2010	9,100	72.8780	72.54 - 73.50
1/27/2010	14,900	71.3706	71.25 - 71.52
1/27/2010	21,000	70.7124	70.24 - 71.21
1/26/2010	14,200	69.4054	69.19 - 69.68

Trade Date	Quantity Sold	Weighted-Average Price Per Share Sold ($)	Range of Price Paid ($)
1/26/2010	48,200	68.4919	68.00 - 68.80
1/25/2010	6,000	71.5517	71.33 - 71.71
1/25/2010	14,000	68.9207	68.45 - 69.43
1/22/2010	1,000	72.0400
1/22/2010	3,000	73.1600	73.10 - 73.27
1/22/2010	8,000	71.2075	70.66 - 71.47
1/22/2010	8,000	70.1135	69.66 - 70.59
1/21/2010	8,000	72.9738	72.86 - 73.09
1/21/2010	14,600	71.2643	70.82 - 71.66
1/21/2010	23,000	72.4261	71.86 - 72.84
1/20/2010	100	3,382.00
1/20/2010	100	3,385.00
1/20/2010	100	3,388.00
1/20/2010	100	3,390.50
1/20/2010	100	3,393.06	3,393.00 - 3,393.30
1/20/2010	100	3,399.001	3,399.00 - 3,399.01
1/20/2010	200	3,401.005	3,401.00 - 3,401.01
1/20/2010	100	3,415.92
1/20/2010	100	3,429.001	3,429.00 - 3,429.01
1/20/2010	100	3,432.17
1/20/2010	100	3,437.90
1/20/2010	100	3,446.012	3,445.99 - 3,446.10
1/20/2010	100	3,450.00
1/20/2010	100	3,460.00
1/20/2010	100	3,465.00
1/20/2010	100	3,467.00
1/20/2010	200	3,469.00
1/20/2010	100	3,470.00
1/20/2010	100	3,472.00
1/20/2010	100	3,479.44
1/19/2010	200	3,285.495	3,285.00 - 3,285.99
1/19/2010	200	3,287.7665	3,287.58 - 3,288.00
1/19/2010	60	3,291.8833	3,291.50 - 3,292.30
1/19/2010	90	3,292.833	3,292.50 - 3,293.00
1/19/2010	60	3,293.95	3,293.50 - 3,294.40
1/19/2010	130	3,297.9931	3,297.97 - 3,298.00
1/19/2010	40	3,299.775	3,299.10 - 3,300.00
1/19/2010	50	3,300.196	3,300.16 - 3,300.25
1/19/2010	60	3,303.00
1/19/2010	30	3,306.99
1/19/2010	30	3,308.5867	3,308.56 - 3,308.60
1/19/2010	30	3,309.78
1/19/2010	60	3317.90	3,317.80 - 3,318.00
1/19/2010	30	3,322.4167	3,322.00 - 3,322.50

Trade Date	Quantity Sold	Weighted-Average Price Per Share Sold ($)	Range of Price Paid ($)
1/19/2010	30	3,325.15
1/19/2010	30	3,330.80
1/19/2010	145	3,333.1014	3,332.70 - 3,333.60
1/19/2010	125	3,334.0738	3,333.99 - 3,334.50
1/15/2010	100	3,250.00
1/15/2010	100	3,305.00
1/14/2010	200	3,301.15	3,300.80 - 3,301.50
1/14/2010	200	3,303.625	3,303.25 - 3,304.00
1/14/2010	200	3,304.45	3,304.40 - 3,304.50
1/13/2010	100	3,312.04	3,312.00 - 3,312.20
1/13/2010	300	3,314.1333	3,313.90 - 3,314.50
1/13/2010	200	3,315.85	3,315.60 - 3,316.10
1/12/2010	60	3,316.20
1/12/2010	400	3,320.125	3,320.00 - 3,320.50
1/12/2010	300	3,322.24	3,321.90 - 3,322.80
1/12/2010	100	3,323.701	3,323.70 - 3,323.71
1/12/2010	100	3,325.10
1/12/2010	100	3,327.00
1/11/2010	200	3,324.99
1/11/2010	100	3,326.00
1/11/2010	40	3,327.155	3,327.00 - 3,327.40
1/11/2010	40	3,329.25	3,329.00 - 3,329.50
1/11/2010	40	3,330.00
1/11/2010	20	3,333.26	3,333.21 - 3,333.31
1/11/2010	40	3,335.0275	3,335.00 - 3,335.10
1/11/2010	20	3,337.00
1/11/2010	40	3,338.00
1/11/2010	20	3,339.00
1/8/2010	100	3,318.30
1/8/2010	300	3,320.3367	3,320.00 - 3,320.60
1/8/2010	340	3,321.7385	3,321.50 - 3,322.00
1/8/2010	100	3,323.00
1/8/2010	100	3,324.00
1/7/2010	600	3,312.1685	3,312.00 - 3,312.80
1/7/2010	360	3,313.9822	3,313.57 - 3,314.10
1/7/2010	100	3,315.00
1/7/2010	100	3,316.20
1/6/2010	200	3,313.85	3,313.80 - 3,313.90
1/6/2010	200	3,316.55	3,316.50 - 3,316.60
1/5/2010	100	3,310.00
1/5/2010	200	3,314.45	3,314.40 - 3,314.50
1/5/2010	210	3,317.3143	3,317.00 - 3,317.60
1/5/2010	200	3,318.00
1/5/2010	200	3,321.6205	3,321.20 - 3,322.00
1/5/2010	100	3,323.80

Trade Date	Quantity Sold	Weighted-Average Price Per Share Sold ($)	Range of Price Paid ($)
1/5/2010	100	3,325.00
1/5/2010	100	3,326.1990	3,326.10 - 3,326.21
1/4/2010	100	3,298.00
1/4/2010	100	3,300.00
1/4/2010	100	3,303.00
1/4/2010	100	3,304.00
1/4/2010	100	3,306.00
1/4/2010	200	3,313.008	3,313.00 - 3,313.16
1/4/2010	100	3,314.00
1/4/2010	100	3,317.50
1/4/2010	100	3,322.60