- Amended Statement of Beneficial Ownership (SC 13D/A)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D/A

Under the Securities Exchange Act of 1934

(Amendment No. 18)*

Ivanhoe Mines Ltd.

(Name of Issuer)

Common Shares, without par value

(Title of class of securities)

46579N

(CUSIP Number)

Ben Mathews

Rio Tinto plc

2 Eastbourne Terrace

London W2 6LG

United Kingdom

+44 (0) 20 7781 2058

(Name, Address and Telephone Number of Person Authorised to Receive Notices and Communications)

with copy to:

Thomas B. Shropshire, Jr.

Linklaters LLP

One Silk Street

London EC2Y 8HQ

United Kingdom

+44 (0) 20 7456 3223

July 27, 2012

(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. ¨

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. 46579N


1	NAME OF REPORTING PERSON. Rio Tinto plc
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ¨ (b) x (See Item 4)
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANISATION England and Wales
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 510,968,850 (see Items 3 and 5)
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 510,968,850 (see Items 3 and 5)
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON 510,968,850 (see Items 3 and 5)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 51.0 per cent (see Item 5)
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) HC, CO


CUSIP No. 46579N


1	NAME OF REPORTING PERSON. Rio Tinto International Holdings Limited
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ¨ (b) x (See Item 4)
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) AF
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANISATION England and Wales
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 510,968,850 (see Items 3 and 5)
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 510,968,850 (see Items 3 and 5)
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON 510,968,850 (see Items 3 and 5)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 51.0 per cent (see Item 5)
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) HC, CO


CUSIP No. 46579N


1	NAME OF REPORTING PERSON. 7999674 Canada Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) ¨ (b) x (See Item 4)
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) AF
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANISATION Canada
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 510,968,850 (see Items 3 and 5)
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 510,968,850 (see Items 3 and 5)
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON 510,968,850 (see Items 3 and 5)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 51.0 per cent (see Item 5)
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) CO


CUSIP No. 46579N


1	NAME OF REPORTING PERSON. 46117 Yukon Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (c) ¨ (d) x (See Item 4)
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS) AF
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANISATION Canada
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 510,968,850 (see Items 3 and 5)
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 510,968,850 (see Items 3 and 5)
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON 510,968,850 (see Items 3 and 5)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) ¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 51.0 per cent (see Item 5)
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) CO

Item 1. Security and Issuer

This Amendment No. 18 to Schedule 13D amends and supplements the statement on Schedule 13D originally filed by Rio Tinto plc (“ Rio Tinto ”) and Rio Tinto International Holdings Limited (“ RTIH ”, and together with Rio Tinto, 7999674 Canada Inc. and 46117 Yukon Inc., the “ Rio Tinto Companies ”) on November 3, 2006, and amended on September 12, 2007, October 26, 2007, January 7, 2008, April 10, 2008, October 30, 2009, March 4, 2010, July 7, 2010, September 13, 2010, December 14, 2010, February 4, 2011, June 28, 2011, August 24, 2011, September 27, 2011, December 12, 2011, January 26, 2012, April 20, 2012 and May 24, 2012 (as amended and supplemented, the “ Schedule 13D ”) with the Securities and Exchange Commission (the “ SEC ”), relating to the common shares, without par value (the “ Shares ”), of Ivanhoe Mines Ltd., a corporation continued under the laws of the Yukon Territory, Canada (the “ Company ”).

Item 2. Identity and Background.

Item 2 of the Schedule 13D is hereby amended and restated in its entirety as follows:

This Schedule 13D is being filed by Rio Tinto, a public limited company incorporated under the laws of England and Wales, RTIH, a company incorporated under the laws of England and Wales, 7999674 Canada Inc., a company incorporated under the laws of Canada, and 46117 Yukon Inc., a company incorporated under the laws of the Yukon Territory, Canada.

Rio Tinto, through its group companies, has mining operations around the world. RTIH is a wholly owned subsidiary of Rio Tinto and is a major investment holding company for the group. 7999674 Canada Inc. is a wholly owned subsidiary of Rio Tinto and is not engaged in any activities. 46117 Yukon Inc. is a wholly owned subsidiary of Rio Tinto and has not engaged in any activities except in connection with the acquisition of shares pursuant to the rights offering.

The principal executive office of Rio Tinto is located at 2 Eastbourne Terrace, London, W2 6LG, United Kingdom. The principal executive office of RTIH is located at 2 Eastbourne Terrace, London, W2 6LG, United Kingdom. The principal executive office of 7999674 Canada Inc. is located at Suite 1300 - 777 Dunsmuir Street, Vancouver BC, V7Y 1K2, Canada. The principal executive office of 46117 Yukon Inc. is located at 200 - 204 Lambert Street, Whitehorse, YT Y1A 3T2, Canada.

The name, business address, present principal occupation or employment and citizenship of each of the executive officers and directors of each of the Rio Tinto Companies are set forth in Schedule A hereto and are incorporated by reference herein.

During the last five years, none of the Rio Tinto Companies nor, to the best of their knowledge, any of the persons listed in Schedule A hereto has been: (i) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

The Rio Tinto Companies have entered into a Joint Filing Agreement, dated August 2, 2012, a copy of which is filed with this Schedule 13D as Exhibit A, pursuant to which they have agreed to file this Schedule 13D jointly in accordance with the provisions of Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”).

Item 3. Source and Amount of Funds or Other Consideration

Item 3 of the Schedule 13D is hereby amended and supplemented as follows:

On July 27, 2012, pursuant to a rights offering by the Company, RTIH and 46117 Yukon Inc. acquired an aggregate of 133,571,192 Shares, representing 51 per cent. of Shares offered under the rights offering, for an aggregate consideration of US$934,998,344, representing a purchase price of US$7.00 per Share. The rights offering was fully subscribed. Of the 133,571,192 Shares acquired by Rio Tinto, 132,089,180 Shares were acquired pursuant to the basic subscription right and 1,482,012 Shares were acquired pursuant to the additional subscription privilege.

The funds for the purchase were obtained by RTIH and 46117 Yukon Inc. from the working capital of Rio Tinto.

Rio Tinto issued a press release announcing the closing of the rights offering on July 30, 2012, which is filed as Exhibit P hereto and incorporated herein by reference.

Item 4. Purpose of Transaction

Item 4 of the Schedule 13D is hereby amended and supplemented as follows:

Except as otherwise set forth in Item 4 of the Schedule 13D, as amended hereby, none of the Rio Tinto Companies has any present plan or proposal that would relate to, or result in, any of the matters set forth in paragraphs (a) through (j) of Item 4 of Schedule 13D. Notwithstanding the foregoing, the Rio Tinto Companies reserve their rights in full to change their intentions with respect to any and all matters referred to in Item 4 of Schedule 13D as they deem appropriate.

Item 5. Interest in Securities of the Issuer

Item 5 of the Schedule 13D is hereby amended and supplemented as follows:

The responses of the Rio Tinto Companies to Rows (11) through (13) of the cover pages of this Schedule 13D and the information set forth in Item 3 are hereby incorporated by reference in this Item 5.

Upon completion of the rights offering on July 27, 2012, each of the Rio Tinto Companies is deemed to beneficially own 510,968,850 Shares which represents 51.0 per cent of the Company’s outstanding Shares on a fully diluted basis.

Rio Tinto also owns 74,247,460 Series D Warrants of the Company after adjustment to give effect to the rights offering. If Rio Tinto were fully to exercise the Series D Warrants, Rio Tinto would acquire an additional 74,247,460 Shares. Following such issuance, Rio Tinto would beneficially own 585,216,310 Shares representing 54.4 per cent. of the outstanding Shares.

Rio Tinto has anti-dilution rights that permit it to acquire additional securities of the Company so as to maintain its proportional equity interest in the Company. Rio Tinto also has the right, until October 24, 2012, to acquire additional securities under its equity financing right of first offer.

The percentage of Shares is based on 1,001,288,734 outstanding Shares, following completion of the rights offering.

In addition, the Shares deemed beneficially owned by each of the Rio Tinto Companies with respect to which such person (i) has sole voting power, (ii) shares voting power, (iii) has sole dispositive power and (iv) shares dispositive power are listed in the responses to Items 7, 8, 9 and 10, respectively, of the cover page of this Schedule 13D relating to such person.

Except as disclosed in this Schedule 13D, none of the Rio Tinto Companies nor, to the best of their knowledge, any of the persons listed in Schedule A hereto, beneficially owns any Shares or has the right to acquire any Shares.

Except as disclosed in this Schedule 13D, none of the Rio Tinto Companies nor, to the best of their knowledge, any of the persons listed in Schedule A hereto, presently has the power to vote or to direct the vote or to dispose or direct the disposition of any other Shares which they may be deemed to beneficially own.

Except as disclosed in this Schedule 13D, none of the Rio Tinto Companies nor, to the best of their knowledge, any of the persons listed in Schedule A hereto, has effected any transaction in the Shares during the past 60 days.

To the best respective knowledge of the Rio Tinto Companies, no other person has the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the Shares beneficially owned by the Rio Tinto Companies.

Item 7. Materials to be Filed as Exhibits


Exhibit Number		Description

A		Joint Filing Agreement between Rio Tinto plc, Rio Tinto International Holdings Limited, 7999674 Canada Inc. and 46117 Yukon Inc.

B		Private Placement Agreement between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited*

C		Shareholders’ Agreement between Robert M Friedland and Rio Tinto International Holdings Limited*

D		Registration Rights Agreement by and between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited*

E		Amending Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.**

F		Heads of Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.**

G		Amending and Additional Rights Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.***

H		Credit Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.***

*	Filed as an exhibit to the original Schedule 13D on November 3, 2006.

**	Filed as an exhibit to the amended Schedule 13D on September 12, 2007.

***	Filed as an exhibit to the amended Schedule 13D on October 26, 2007.

****	Filed as an exhibit to the amended and restated Schedule 13D on December 14, 2010.

*****

Filed as an exhibit to the amended Schedule 13D on June 28, 2011.

******

Filed as an exhibit to the amended Schedule 13D on August 24, 2011.

*******

Filed as an exhibit to the amended Schedule 13 D on January 26, 2012.


Exhibit Number		Description

I		Heads of Agreement between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited dated December 8, 2010****

J		Agreement between RTIH and the Government of Mongolia dated June 8, 2011*****

K		Press Release dated August 24, 2011******

L		Private Placement Agreement between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited dated January 18, 2012*******

M		Press Release dated January 24, 2012*******

N		Memorandum of Agreement between Rio Tinto plc and Ivanhoe Mines Ltd. dated April 17, 2012********

O		Amending Agreement between Rio Tinto plc and Ivanhoe Mines Ltd. dated May 22, 2012*********

P		Press Release dated July 30, 2012

********

Filed as an exhibit to the amended Schedule 13 D on April 20, 2012.

*********

Filed as an exhibit to the amended Schedule 13 D on May 24, 2012.

SIGNATURES

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

Dated: August 2, 2012


Rio Tinto plc

By:		/s/ Ben Mathews
		Signature

		Ben Mathews / Company Secretary
		Name/Title

Rio Tinto International Holdings Limited

By:		/s/ Ben Mathews
		Signature

		Ben Mathews / Director
		Name/Title

7999674 Canada Inc.

By:		/s/ Ben Mathews
		Signature

		Ben Mathews / Assistant Corporate Secretary
		Name/Title


46117 Yukon Inc.

By:		/s/ Julie Parent
		Signature

		Julie Parent / Secretary
		Name/Title

SCHEDULE A

The response set forth in Schedule A of the Schedule 13D is hereby amended and restated in its entirety with the information below:

Rio Tinto plc

Directors and Executive Officers


Name	Present Principal Occupation	Business Address	Citizenship
*Directors*

Jan du Plessis	Chairman of Rio Tinto	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

Tom Albanese	Chief Executive of Rio Tinto	2 Eastbourne Terrace London W2 6LG United Kingdom	United States of America

Guy Elliott	Finance Director of Rio Tinto	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

Sam Walsh	Chief Executive of the Iron Ore Group	120 Collins Street Melbourne Victoria 3000 Australia	Australia

Robert Brown	Company Director	1188 Sherbrooke Street West, Montreal, Quebec H3A 3G2, Canada	Canada

Vivienne Cox	Company Director	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

Mike Fitzpatrick	Company Director	120 Collins Street Melbourne Victoria 3000 Australia	Australia

Ann Godbehere	Company Director	2 Eastbourne Terrace London W2 6LG United Kingdom	Canada and United Kingdom

Richard Goodmanson	Company Director	2 Eastbourne Terrace London W2 6LG United Kingdom	United States of America

Lord Kerr	Company Director	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

Christopher Lynch	Company Director	120 Collins Street Melbourne Victoria 3000 Australia	Australia


Name	Present Principal Occupation	Business Address	Citizenship

Paul Tellier	Company Director	1188 Sherbrooke Street West, Montreal, Quebec H3A 3G2, Canada	Canada

John Varley	Company Director	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

*Executive Officers*

Hugo Bagué	Group Executive, People and Organisation	2 Eastbourne Terrace London W2 6LG United Kingdom	Belgium

Preston Chiaro	Group Executive, Technology & Innovation	4700 Daybreak Parkway South Jordan, Utah 84095 United States	United States of America

Bret Clayton	Group Executive, Business Support and Operations	2 Eastbourne Terrace London W2 6LG United Kingdom	United States of America

Jacynthe Coté	Chief Executive of Rio Tinto Alcan	2 Eastbourne Terrace London W2 6LG United Kingdom	Canada

Andrew Harding	Chief Executive of Rio Tinto Copper	2 Eastbourne Terrace London W2 6LG United Kingdom	Australia

Harry Kenyon-Slaney	Chief Executive of Rio Tinto Diamonds & Minerals	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

Doug Ritchie	Chief Executive of Rio Tinto Energy	3 West Tower 410 Ann Street Brisbane, QLD 4000 Australia	Australia

Debra Valentine	Group Executive, Legal and External Affairs	2 Eastbourne Terrace London W2 6LG United Kingdom	United States of America

Rio Tinto International Holdings Limited Directors and Executive Officer

*Directors*

Dan Larsen	Director	2 Eastbourne Terrace London W2 6LG United Kingdom	United States of America

Janine Juggins	Director	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

Ulf Quellmann	Director	2 Eastbourne Terrace London W2 6LG United Kingdom	Germany


Name	Present Principal Occupation	Business Address	Citizenship

Ben Mathews	Director	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

*Executive Officer*

Gemma Aldridge	Secretary	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

7999674 Canada Inc. Directors and Executive Officer

*Directors*

Jocelin Paradis	Director	1188 Sherbrooke Street West Montreal QC H3A 3G2 Canada	Canada

Julie Parent	Director	1188 Sherbrooke Street West Montreal QC H3A 3G2 Canada	Canada

*Executive Officer*

Jocelin Paradis	President	1188 Sherbrooke Street West Montreal QC H3A 3G2 Canada	Canada

Lawrence Tal	Vice President	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom

Brett Salt	Vice President	2 Eastbourne Terrace London W2 6LG United Kingdom	Australia

Julie Parent	Corporate Secretary	1188 Sherbrooke Street West Montreal QC H3A 3G2 Canada	Canada

Ben Mathews	Assistant Corporate Secretary	2 Eastbourne Terrace London W2 6LG United Kingdom	United Kingdom


Name	Present Principal Occupation	Business Address	Citizenship

46117 Yukon Inc. Directors and Executive Officer

*Directors*

Jocelin Paradis	Director	1188 Sherbrooke Street West Montreal QC H3A 3G2 Canada	Canada

*Executive Officer*

Jocelin Paradis	President	1188 Sherbrooke Street West Montreal QC H3A 3G2 Canada	Canada

Julie Parent	Vice President	1188 Sherbrooke Street West Montreal QC H3A 3G2 Canada	Canada

EXHIBIT INDEX


Exhibit Number		Description

A		Joint Filing Agreement between Rio Tinto plc, Rio Tinto International Holdings Limited, 7999674 Canada Inc. and 46117 Yukon Inc.

B		Private Placement Agreement between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited*

C		Shareholders’ Agreement between Robert M Friedland and Rio Tinto International Holdings Limited*

D		Registration Rights Agreement by and between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited*

E		Amending Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.**

F		Heads of Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.**

G		Amending and Additional Rights Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.***

H		Credit Agreement between Rio Tinto International Holdings Limited and Ivanhoe Mines Ltd.***

I		Heads of Agreement between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited dated December 8, 2010****

J		Agreement between RTIH and the Government of Mongolia dated June 8, 2011*****

K		Press Release dated August 24, 2011******

L		Private Placement Agreement between Ivanhoe Mines Ltd. and Rio Tinto International Holdings Limited dated January 18, 2012*******

M		Press Release dated January 24, 2012*******

N		Memorandum of Agreement between Rio Tinto plc and Ivanhoe Mines Ltd. dated April 17, 2012********

O		Amending Agreement between Rio Tinto plc and Ivanhoe Mines Ltd. dated May 22, 2012*********