UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

x

Rule 13d-1(b)

o

Rule 13d-1(c)

o

Rule 13d-1(d)

CUSIP No. 602675100

1.

Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only)
Schroder Investment Management North America Ltd

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
England

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
1,661,119

6.

Shared Voting Power
0

7.

Sole Dispositive Power
1,661,119

8.

Shared Dispositive Power
0

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
1,661,119

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)
1.385% of outstanding shares

12.

Type of Reporting Person (See Instructions)
IA

CUSIP No. 602675100

1.

Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only)
Schroder Investment Management Ltd

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
England

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
2,325,973

6.

Shared Voting Power
0

7.

Sole Dispositive Power
2,325,973

8.

Shared Dispositive Power
0

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
2,325,973

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)
1.940% of outstanding shares

12.

Type of Reporting Person (See Instructions)
FI

CUSIP No. 602675100

1.

Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only)
Schroder Investment Management Hong Kong Ltd

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
Hong Kong

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
1,164,100

6.

Shared Voting Power
0

7.

Sole Dispositive Power
1,164,100

8.

Shared Dispositive Power
0

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
1,164,100

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)
0.971% of outstanding shares

12.

Type of Reporting Person (See Instructions)
FI

CUSIP No. 602675100

1.

Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only)
Schroder Investment Management Singapore Ltd

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
Singapore

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
930,475

6.

Shared Voting Power
0

7.

Sole Dispositive Power
930,475

8.

Shared Dispositive Power
0

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
930,475

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)
0.776% of outstanding shares

12.

Type of Reporting Person (See Instructions)
FI

Item 1.

(a)

Name of Issuer
Mindray Medical

(b)

Address of Issuer’s Principal Executive Offices
Mindray Building, Keji 12 Road South

Hi-Tech Industrial Park, Nanshan

Shenzhen 518057

People’s Republic of China

Item 2.

(a)

Name of Person Filing
Schroder Investment Management North America Inc

(b)

Address of Principal Business Office or, if none, Residence
875 Third Ave, 22nd Floor

New York, NY 10022

(c)

Citizenship
USA

(d)

Title of Class of Securities
ADR

(e)

CUSIP Number
602675100

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)

x

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 association 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

A non-U.S. institution in accordance with § 240.13d–1(b)(1)(ii)(J);

(k)

o

Group, in accordance with § 240.13d–1(b)(1)(ii)(K). If filing as a non-U.S. institution in accordance with § 240.13d–1(b)(1)(ii)(J), please specify the type of institution:____________________________

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:   

6,081,667

(b)

Percent of class:   

5.07% of outstanding shares

(c)

Number of shares as to which the person has:

(i)

Sole power to vote or to direct the vote   

1,661,119

(ii)

Shared power to vote or to direct the vote    

4,420,548

(iii)

Sole power to dispose or to direct the disposition of   

6,081,667

(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

Schroder Investment Management Ltd. is an FSA-registered investment adviser under common control with the adviser.  It is located in the United Kingdom at 31 Gresham Street, London EC2V 7QA.  Schroder Investment Management North America Ltd. disclaims the existence of a group.

Item 9.

Notice of Dissolution of Group

Not applicable.

Item 10.

Certification

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

February 11, 2013

By:

/s/ Jamie Dorrien Smith**

Name:

Jamie Dorrien Smith**

Title:

Chief Executive Officer

Schroder Investment Management North America Inc

** Authorized by Power of Attorney to sign on behalf of the following Advisor:

Schroder Investment Management North America Ltd

Schroder Investment Management Ltd

Schroder Investment Management Hong Kong Ltd

Schroder Investment Management Singapore Ltd

Schroder Investment Management North America Limited

31 Gresham Street, London EC2V 7QA

Tel: 020 7658 6000 Fax: 020 7658 6965

www.schroders.com

Name/Title of signatory:

Gareth Taylor – Director

Matthew Whyte – For and on behalf of Schroders Corporate Secretary Limited, Company Secretary

Signature:

/s/ Gareth Taylor

/s/ Matthew Whyte

Schroder Investment Management Limited

31 Gresham Street, London EC2V 7QA

Tel: 020 7658 6000 Fax: 020 7658 6965

www.schroders.com

Name/Title of signatory:

Markus Ruetimann – Director

Helen Horton – For and on behalf of Schroders Corporate Secretary Limited, Company Secretary

Signatures:

/s/ Markus Ruetimann

/s/ Helen Horton

Name/Title of signatory:

Steve Bryant, Director

Signature:

/s/ Steve Bryant

Name/Title of signatory:

Tan Jui Tong

Tricia Feng Ti Shiang

Director

Secretary

Signature:

/s/ Tan Jui Tong

/s/ Tricia Feng Ti Shiang

Address of representative:

875 Third Avenue, 22nd Floor, New York, NY 10022

Name of representative:

Schroder Investment Management North America Inc.

Jamie Dorrien-Smith, Chief Executive Officer