MFN Minefinders Corp. Ltd. Ordinary Shares

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 40-F

[   ] REGISTRATION STATEMENT PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934

OR

[ X ]   ANNUAL REPORT PURSUANT TO SECTION 13(a) OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2011

Commission file number: 001-31586

MINEFINDERS CORPORATION LTD.
(Exact Name of Registrant as Specified in its Charter)

2288 – 1177 West Hastings Street
Vancouver, British Columbia, Canada V6E 2K3
(604) 687-6263
(Address and Telephone Number of Registrant’s Principal Executive Offices)

Securities registered or to be registered pursuant to Section 12(b) of the Act:

Securities registered or to be registered pursuant to Section 12(g) of the Act: N/A

Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act: N/A

For annual reports, indicate by check mark the information filed with this form:

[ X ] Annual Information Form [ X ] Audited Annual Financial Statements

Indicate the number of outstanding shares of each of the issuer's classes of capital or common stock as of the close of the period covered by the annual report: 86,933,927

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange Act during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days.

[ X ] Yes [   ] No

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) du ring the pr ece ding 12 months (or for such shorter period that the registrant was required to submit and post such files).

[ X ] Yes [   ] No

EXPLANATORY NOTE

Minefinders Corporation Ltd. (the “Company” or the “Registrant”) is a Canadian issuer eligible to file its annual report pursuant to Section 13 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) on Form 40-F pursuant to the multi-jurisdictional disclosure system of the Exchange Act . The equity securities of the Company are accordingly exempt from Sections 14(a), 14(b), 14(c), 14(f) and 16 of the Exchange Act pursuant to Rule 3a12-3 thereunto.

FORWARD-LOOKING STATEMENTS

This annual report on Form 40-F and the exhibits attached hereto contain “forward-looking statements”, within the meaning of the United States Private Securities Litigation Reform Act of 1995. These statements relate to analyses and other information that are based on forecasts of future results, estimates of amounts not yet determinable and assumptions of management.

Statements concerning mineral reserves and resource estimates may also be deemed to constitute forward-looking statements to the extent that they involve estimates of the mineralization that will be encountered if a property is developed. Any statements that express or involve discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions or future events or performance (often, but not always, using words or phrases such as ‘‘expects,’’ ‘‘anticipates,’’ ‘‘plans,’’ ‘‘projects,’’ ‘‘estimates,’’ ‘‘assumes,’’ ‘‘intends,’’ ‘‘strategy,’’ ‘‘goals,’’ ‘‘objectives,’’ ‘‘potential’’ or variations thereof or stating that certain actions, events or results ‘‘may,’’ ‘‘could,’’ ‘‘would,’’ ‘‘might’’ or ‘‘will’’ be taken, occur or be achieved, or the grammatical and negative variations of any of these terms and similar expressions) are not statements of historical fact and may be ‘‘forward-looking statements.’’ Forward-looking statements are subject to a variety of known and unknown risks, uncertainties and other factors that could cause actual events or results to differ from those expressed or implied by the forward-looking statements, including, without limitation:

• risks related to the Company’s limited history of revenues from mining operations and risks relating to the Company’s ability to successfully produce precious metals profitably;

• risks related to the proposed transaction with Pan American Silver;

• uncertainty in the Company’s ability to fund and risks related to the availability of funding the development of its mineral properties or the completion of further exploration programs;

• risks related to the Company’s ability to successfully negotiate and maintain agreements with the Ejido Huizopa or its members;

• risks related to the fluctuation of interest rates and the leverage ratio under the revolving credit facility;

• risks related to accelerated payment obligations due to events of default under the revolving credit facility and/or the 4.50% convertible senior notes;

• risks related to uncertain and volatile economic conditions;

• risks related to changes in the market prices of gold, silver and other minerals which in the past have fluctuated widely and which could affect the profitability of the Company’s operations and financial condition;

• risks related to market events and conditions including the Company’s access to credit and capital;

• risks related to differences between US and Canadian practices for reporting resources and reserves;

• uncertainty as to actual costs, production and economic returns with no assurance of profitable mining operations;

• risks related to future drilling results which may not produce reserves and resources that can be mined or processed profitably;

• risks related to the Company’s reserves and resources figures being estimates based on interpretations and assumptions which may result in less mineral production under actual conditions than is currently estimated;

• risks related to currency fluctuations;

• risks related to the use of heap leaching and hazardous materials, such as sodium cyanide, in the production of gold and silver;

• risks related to the inherently dangerous activity of mining, including conditions or events beyond the Company’s control;

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• risks related to governmental regulations;

• risks related to the Company’s business being subject to environmental laws and regulations which may increase its costs of doing business and restrict its operations;

• risks related to the Company’s primary properties being located in Mexico, including political, economic and regulatory instability;

• uncertainty in the Company’s ability to obtain and maintain certain permits necessary to its current and anticipated operations;

• risks related to the Company’s land reclamation requirements which may be burdensome;

• uncertainty regarding future requirements to fund additional reclamation work during the course of the Company’s mining activities;

• uncertainty relating to the Company’s ability to attract and maintain qualified management to meet the needs of its anticipated growth, and risks relating to its ability to manage growth effectively;

• risks related to the Company’s mineral properties being subject to prior unregistered agreements, transfers, or claims and other defects in title;

• risks related to the Company’s history of losses, which may continue in the future;

• risks related to increased competition that could adversely affect the Company’s ability to attract necessary capital funding or acquire suitable properties for mineral exploration and development in the future; and

• risks related to the Company’s officers and directors becoming associated with other natural resource companies which may give rise to conflicts of interests.

This list is not exhaustive of the factors that may affect any of the Company’s forward-looking statements. Some of the important risks and uncertainties that could affect forward-looking statements are described further in the exhibits attached to this annual report on Form 40-F. Should one or more of these risks and uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in the forward-looking statements. The Company’s forward-looking statements are based on the beliefs, expectations and opinions of management on the date the statements are made and the Company does not assume any obligation to update forward-looking statements if circumstances or management’s beliefs, expectations or opinions should change, except as may be required by law. For the reasons set forth above, investors should not place undue reliance on forward-looking statements.

NOTE TO UNITED STATES READERS -
DIFFERENCES IN UNITED STATES AND CANADIAN REPORTING PRACTICES

The Company is permitted, under the multi-jurisdictional disclosure system adopted by the United States Securities and Exchange Commission (the “SEC”), to prepare this annual report in accordance with Canadian disclosure requirements, which differ from those of the United States. Effective January 1, 2011, the Company began preparing its financial statements, which are filed with this annual report on Form 40-F, in accordance with International Financial Reporting Standards (“IFRS”). Accordingly, the Company’s financial statements are not comparable to financial statements of United States companies. Details on the adoption of IFRS are described in Note 22 to the audited consolidated financial statements of the Company.

CURRENCY

Unless otherwise indicated, all dollar amounts in this annual report on Form 40-F are in United States dollars. The exchange rate of Canadian dollars into United States dollars, on December 30, 2011, based upon the noon exchange rate as quoted by the Bank of Canada, was U.S.$1.00 = CDN$ 1.0170 .

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ANNUAL INFORMATION FORM

The Company’s Annual Information Form (“AIF”) for the fiscal year ended December 31, 2011 is filed as Exhibit 1 and incorporated by reference in this annual report on Form 40-F.

RESOURCE AND RESERVE ESTIMATES

The Company’s AIF filed as Exhibit 1 to this annual report on Form 40-F has been prepared in accordance with the requirements of the securities laws in effect in Canada, which differ from the requirements of United States securities laws. The terms “mineral reserve”, “proven mineral reserve” and “probable mineral reserve” are Canadian mining terms as defined in accordance with Canadian National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”) and the Canadian Institute of Mining, Metallurgy and Petroleum’ (the “CIM”) - CIM Definition Standards on Mineral Resources and Mineral Reserves , adopted by the CIM Council, as amended. These definitions differ from the definitions in the SEC Industry Guide 7. Under SEC Industry Guide 7 standards, a “final” or “bankable” feasibility study is required to report reserves, the three-year historical average price is used in any reserve or cash flow analysis to designate reserves and the primary environmental analysis or report must be filed with the appropriate governmental authority.

In addition, the terms “mineral resource”, “measured mineral resource”, “indicated mineral resource” and “inferred mineral resource” are defined in and required to be disclosed by NI 43-101; however, these terms are not defined terms under SEC Industry Guide 7 and are normally not permitted to be used in reports and registration statements filed with the SEC. Investors are cautioned not to assume that all or any part of a mineral deposit in these categories will ever be converted into reserves. “Inferred mineral resources” have a great amount of uncertainty as to their existence, and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all or any part of an inferred mineral resource will ever be upgraded to a higher category. Under Canadian rules, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies, except in rare cases. Investors are cautioned not to assume that all or any part of an inferred mineral resource exists or is economically or legally mineable. Disclosure of “contained ounces” in a resource is permitted disclosure under Canadian regulations; however, the SEC normally only permits issuers to report mineralization that does not constitute “reserves” by SEC standards as in place tonnage and grade without reference to unit measures.

Accordingly, information contained in this annual report on Form 40-F and the documents incorporated by reference herein containing descriptions of our mineral deposits may not be comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements under United States federal securities laws and the rules and regulations thereunder.

AUDITED ANNUAL FINANCIAL STATEMENTS AND MANAGEMENT’S DISCUSSION AND ANALYSIS

Audited Annual Financial Statements

The audited consolidated financial statements of the Company for the years ended December 31, 2011 and 2010, including the reports of the independent registered public accounting firm with respect thereto, are filed as Exhibit 2 and incorporated by reference in this annual report on Form 40-F.

Management’s Discussion and Analysis

The Company’s management’s discussion and analysis (“MD&A”) is filed as Exhibit 3 and incorporated by reference in this annual report on Form 40-F.

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TAX MATTERS

Shareholders should be aware that the acquisition, ownership, and disposition of common shares of the Company may have tax consequences under the laws of both Canada and the United States. Shareholders are solely responsible for determining the tax consequences applicable to their particular circumstances and should consult their own tax advisors concerning an investment in the Company’s common shares.

CONTROLS AND PROCEDURES

Disclosure Controls and Procedures

At the end of the period covered by this annual report on Form 40-F, the fiscal year ended December 31, 2011, an evaluation was carried out under the supervision of and with the participation of the Company’s management, including the Chief Executive Officer (“CEO”) and Chief Financial Officer (“CFO”), of the effectiveness of the design and operations of the Company’s disclosure controls and procedures (as defined in Rule 13a – 15(e) and Rule 15d – 15(e) under the Exchange Act). Based on that evaluation the CEO and the CFO have concluded that, as of the end of the period covered by this annual report, the Company’s disclosure controls and procedures were adequately designed and effective in ensuring that: (i) information required to be disclosed by the Company in reports that it files or submits to the SEC under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and (ii) material information required to be disclosed in the Company’s reports filed under the Exchange Act is accumulated and communicated to our management, including our CEO and CFO, as appropriate, to allow for accurate and timely decisions regarding required disclosure.

Management’s Report on Internal Control over Financial Reporting

The Company's management is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act. The Company’s management has employed a framework consistent with Rule 13a-15(c) under the Exchange Act, to evaluate the Company’s internal control over financial reporting as described below. The Company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation and fair presentation of financial statements for external purposes in accordance with IFRS.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

The Company’s management assessed the effectiveness of the Company’s internal control over financial reporting as of December 31, 2011. In making this assessment, the Company’s management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in Internal Control-Integrated Framework . Based upon its assessment, management concluded that, as of December 31, 2011, the Company’s internal control over financial reporting was effective.

The Company is required to provide an auditor’s attestation report on internal control over financial reporting for the fiscal year ended December 31, 2011. In this annual report, the Company’s independent registered auditor, KPMG LLP (“KPMG”), must state its opinion as to the effectiveness of the Company’s internal control over financial reporting for the fiscal year ended December 31, 2011. KPMG has issued an auditors’ report on the effectiveness of the Company’s internal control over financial reporting.

Auditor’s Attestation Report

KPMG’s attestation report on the Company’s internal control over financial reporting is included as part of Exhibit 2 and incorporated by reference in this annual report on Form 40-F.

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Changes in Internal Control over Financial Reporting

During the period covered by this annual report on Form 40-F, no changes occurred in the Company’s internal control over financial reporting that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.

The Company’s management, including the CEO and CFO, does not expect that its disclosure controls and procedures or internal controls and procedures will prevent all error and all fraud. A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Further, the design of a control system must reflect the fact that there are resource constraints, and the benefits of controls must be considered relative to their costs. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues and instances of fraud, if any, within the Company have been detected. These inherent limitations include the realities that judgments in decision-making can be faulty, and that breakdowns can occur because of simple error or mistake. Additionally, controls can be circumvented by the individual acts of some persons, by collusion of two or more people, or by management override of the control. The design of any system of controls also is based in part upon certain assumptions about the likelihood of future events, and there can be no assurance that any design will succeed in achieving its stated goals under all potential future conditions; over time, control may become inadequate because of changes in conditions, or the degree of compliance with the policies or procedures may deteriorate. Because of the inherent limitations in a cost-effective control system, misstatements due to error or fraud may occur and not be detected.

CORPORATE GOVERNANCE

The Company’s Board of Directors (the “Board of Directors” or “Board”) is responsible for the Company’s Corporate Governance policies and has separately designated standing Compensation, Nominating and Technical and Commercial Oversight Committees. The Company’s Board of Directors has determined that all the members of the Compensation, Nominating, and Technical and Commercial Oversight Committees are independent, based on the criteria for independence and unrelatedness prescribed by Section 803(A) of the NYSE Amex Equities (the “NYSE Amex”) Company Guide.

Compensation

Compensation of the Company’s CEO and all other officers is recommended to the Board for determination by the Compensation Committee. The Compensation Committee develops, reviews and monitors director and executive compensation and policies. The Compensation Committee is also responsible for annually reviewing the adequacy of compensation for directors and others and the composition of compensation packages. The Company’s CEO cannot be present during the Compensation Committee’s deliberations or vote.

Nominating Committee

Nominees for the election to the Board of Directors are recommended by the Nominating Committee. The Nominating Committee’s responsibilities include considering annually the size and composition of the Board and the qualifications of incumbent directors and recommending to the Board such changes as it sees fit; identifying and recommending, annually, qualified persons to be nominated for election or re-election to the Board; reviewing changes in applicable laws, emerging practices or other initiatives relating to directors or boards of directors; providing orientation programs for new directors and continuing development programs for existing directors; and reviewing annually the functioning of the Nominating Committee.

Technical and Commercial Oversight Committee

The responsibilities of the Technical and Commercial Oversight Committee include: considering and evaluating technical studies prepared by or for the Company; recommending to the Board annual mine plans and budgets

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derived from those plans; evaluating long-term mine plans; and reviewing the impact of proposed changes in applicable laws, emerging practices and other technical initiatives in the mining industry.

AUDIT COMMITTEE

The Company has a separately designated standing Audit Committee established in accordance with Section 3(a)(58)(A) of the Exchange Act. The Company’s Audit Committee comprises Robert L. Leclerc, James M. Dawson and H. Leo King, all of whom, in the opinion of the Board of Directors, are independent (as determined under Rule 10A-3 of the Exchange Act and Sections 803(A) and 803(B) of the NYSE Amex Company Guide) and are financially literate. The Audit Committee meets the requirements set forth by the NYSE Amex Company Guide Section 803(B).

Mr. Leclerc is a lawyer, and was the chief executive officer of a large law firm from 1993 to 1996. From 1997 to 2003 he was chief executive officer of a public company that was in the business of mining precious metals, and was listed for trading in Canada and the U.S.A. In those capacities he was ultimately responsible for the activity and authority of the chief financial officers who reported to him, and for the implementation and maintenance of internal control systems and for compliance with the required public reporting.

Mr. Dawson has been a professional consulting geologist for over thirty years, and has been a director of public companies in the mineral resource industry for almost twenty years. He has also managed his own consulting geological firm for many years. In these capacities he has acquired a knowledge and understanding of the financial issues and accounting principles that are relevant in assessing the Company’s financial disclosures and internal control systems.

Mr. King is a professional geologist who has nearly twenty years of experience in senior executive positions within the base and precious metals mining industry. He is the president and a director of a public company, and his responsibilities have included the operation of internal control systems and compliance with public financial disclosure requirements. In discharging these responsibilities Mr. King has acquired the requisite skill and knowledge in understanding the accounting principles, and their application, adopted by this Company in its financial disclosures.

The members of the Audit Committee do not have fixed terms and are appointed and replaced from time to time by resolution of the Board of Directors.

The Audit Committee meets with the President and CEO and the CFO of the Company and the Company’s independent auditors to review and inquire into matters affecting financial reporting, the system of internal accounting and financial controls, as well as audit procedures and audit plans. The Audit Committee also recommends to the Board of Directors the auditors to be appointed. In addition, the Audit Committee reviews and recommends to the Board of Directors for approval the annual financial statements and MD&A, reviews and approves the interim financial statements and MD&A and undertakes other activities required by regulatory authorities.

The full text of the Company’s Audit Committee Charter is attached to the Company’s AIF (filed as Exhibit 1 and incorporated by reference in this annual report on Form 40-F) as an Appendix. The Audit Committee has reviewed and reassessed the adequacy of the Company’s Audit Committee charter.

Audit Committee Financial Expert

The Board of Directors has not designated an “audit committee financial expert” within the meaning of applicable United States securities rules and regulations. Each member of the Audit Committee is financially literate, and, in accordance with NYSE Amex Company Guide Section 803(B)(2)(iii), the Board of Directors has determined that Mr. Leclerc is financially sophisticated based on his experience as the chief executive officer of a large law firm (1993 to 1996) and of a company whose shares were listed and traded in the United States and Canada (1997 to

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2003). Mr. Leclerc was ultimately responsible for the activity and authority conferred regularly on the chief financial officers who reported to him. However, Mr. Leclerc did not assume an active role in supervising others engaged in the preparation, audit, analysis or evaluation of financial statements. Mr. Leclerc has no accreditation to perform such work.

The Board of Directors has determined that the experience of the members of the Audit Committee, as directors of publicly traded companies, is sufficient to ensure compliance with requisite regulatory requirements. The need to add an audit committee financial expert will be monitored as the Company grows and its financial reporting and internal control challenges increase.

PRINCIPAL ACCOUNTING FEES AND SERVICES – INDEPENDENT AUDITOR

The following table shows the aggregate fees billed to the Company by KPMG in 2011 and 2010.

PRE-APPROVAL OF AUDIT AND NON-AUDIT SERVICES PROVIDED BY INDEPENDENT AUDITOR

The Audit Committee pre-approves all audit and non-audit services to be provided to the Company by its independent auditor. Non-audit services that are prohibited from being provided to the Company by its independent auditors may not be pre-approved. In addition, prior to the granting of any pre-approval, the Audit Committee must be satisfied that the performance of the services in question will not compromise the independence of the independent auditor. Since the enactment of the Sarbanes-Oxley Act of 2002, all non-audit services performed by the Company’s auditor for the fiscal year ended December 31, 2011 have been pre-approved by the Audit Committee of the Company. No non-audit services were approved pursuant to the de minimis exemption to the pre-approval requirement.

OFF-BALANCE SHEET TRANSACTIONS

The Company does not have any off-balance sheet financing arrangements or relationships with unconsolidated special purpose entities.

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CODE OF ETHICS

The Company has adopted a Code of Business Conduct and Ethics (the “Code”) that applies to all the Company’s directors, executive officers and employees, which was previously filed as Exhibit 14 to the Company’s annual report on Form 40-F for the year ended December 31, 2004, filed with the SEC on March 29, 2005 and is incorporated herein by reference. The Code is available to any person, without charge, by written request to the Company at its principal executive office in Vancouver, British Columbia, Canada.

During the fiscal year ended December 31, 2011, the Company did not substantially amend, waive, or implicitly waive any provision of the Code with respect to any of the directors, executive officers or employees subject to it.

CONTRACTUAL OBLIGATIONS

Our disclosure of contractual obligations is provided under the heading “Management’s Discussion and Analysis —Capital Resources and Liquidity – Contractual Obligations and Commitments ” contained in Exhibit 3 as filed with this annual report on Form 40-F and is incorporated by reference herein.

NOTICES PURSUANT TO REGULATION BTR

There were no notices required by Rule 104 of Regulation BTR that the Registrant sent during the year ended December 31, 2011 concerning any equity security subject to a blackout period under Rule 101 of Regulation BTR.

NYSE AMEX CORPORATE GOVERNANCE

The Company’s common shares are listed on the NYSE Amex. Section 110 of the NYSE Amex Company Guide permits the NYSE Amex to consider the laws, customs and practices of foreign issuers in relaxing certain NYSE Amex listing criteria, and to grant exemptions from NYSE Amex listing criteria based on these considerations. A company seeking relief under these provisions is required to provide written certification from independent local counsel that the non-complying practice is not prohibited by home country law. A description of the significant ways in which the Company’s governance practices differ from those followed by domestic companies pursuant to NYSE Amex standards is as follows:

Shareholder Meeting Quorum Requirement : The NYSE Amex minimum quorum requirement for a shareholder meeting is one-third of the outstanding shares of common stock. In addition, a company listed on NYSE Amex is required to state its quorum requirement in its bylaws. The Company’s quorum requirement is set forth in its Articles and Bylaws. A quorum for a meeting of members of the Company is two persons who are, or who represent by proxy, shareholders who, in the aggregate, hold at least 5% of the shares entitled to be voted at the meeting.

Proxy Delivery Requirement : The NYSE Amex requires the solicitation of proxies and delivery of proxy statements for all shareholder meetings, and requires that these proxies shall be solicited pursuant to a proxy statement that conforms to SEC proxy rules. The Company is a “foreign private issuer” as defined in Rule 3b-4 under the Exchange Act, and the equity securities of the Company are accordingly exempt from the proxy rules set forth in Sections 14(a), 14(b), 14(c) and 14(f) of the Exchange Act. The Company solicits proxies in accordance with applicable rules and regulations in Canada.

Shareholder Approval Requirement: The Company will follow Toronto Stock Exchange rules for shareholder approval of new issuances of its common shares. Following Toronto Stock Exchange rules, shareholder approval is required for certain issuances of shares that: (i) materially affect control of the Company; or (ii) provide consideration to insiders in aggregate of 10% or greater of the market capitalization of the listed issuer and have not been negotiated at arm’s length. Shareholder approval is also required, pursuant to Toronto Stock Exchange rules, in the case of private placements: (x) for an aggregate number of listed securities issuable greater than 25% of the number of securities of the listed issuer which are outstanding, on a non-diluted basis, prior to the date of closing of the transaction if the price per security is less than the market price; or (y) that during any six month period are to insiders for listed

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securities or options, rights or other entitlements to listed securities greater than 10% of the number of securities of the listed issuer which are outstanding, on a non-diluted basis, prior to the date of the closing of the first private placement to an insider during the six month period.

The foregoing are consistent with the laws, customs and practices in Canada.

In addition, the Company may from time-to-time seek relief from NYSE Amex corporate governance requirements on specific transactions under Section 110 of the NYSE Amex Company Guide by providing written certification from independent local counsel that the non-complying practice is not prohibited by our home country law, in which case, the Company shall make the disclosure of such transactions available on the Company’s website at www.minefinders.com. Information contained on the Company’s website is not part of this annual report.

MINE SAFETY DISCLOSURE

Pursuant to Section 1503(a) of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (“Dodd-Frank Act”), issuers that are operators, or that have a subsidiary that is an operator, of a coal or other mine in the United States are required to disclose in their periodic reports filed with the SEC information regarding specified health and safety violations, orders and citations, related assessments and legal actions, and mining-related fatalities under the regulation of the Federal Mine safety and Health Administration under the Federal Mine Safety and Health Act of 1977. During the fiscal year ended December 31, 2011, the Company had no mines in the United States.

UNDERTAKING

The Company undertakes to make available, in person or by telephone, representatives to respond to inquiries made by the SEC staff, and to furnish promptly, when requested to do so by the SEC staff, information relating to: the securities registered pursuant to Form 40-F; the securities in relation to which the obligation to file an annual report on Form 40-F arises; or transactions in said securities.

CONSENT TO SERVICE OF PROCESS

The Company filed an Appointment of Agent for Service of Process and Undertaking on Form F-X with the SEC on November 24, 2010, which is hereby incorporated by reference, with respect to the class of securities in relation to which the obligation to file this annual report on Form 40-F arises.

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EXHIBITS

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SIGNATURES

Pursuant to the requirements of the Exchange Act, the Registrant certifies that it meets all of the requirements for filing on Form 40-F and has duly caused this annual report to be signed on its behalf by the undersigned, thereto duly authorized.

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CERTIFICATION PURSUANT TO

18 U.S.C. §1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the annual report of Minefinders Corporation Ltd. (the “Company”) on Form 40-F for the period ended December 31, 2011 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Mark H. Bailey, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in this Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

A signed original of this written statement required by Section 906 has been provided to Minefinders Corporation Ltd. and will be retained by Minefinders Corporation Ltd. and furnished to the Securities and Exchange Commission or its staff upon request.

CERTIFICATION PURSUANT TO

18 U.S.C. §1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the annual report of Minefinders Corporation Ltd. (the “Company”) on Form 40-F for the period ended December 31, 2011 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Greg D. Smith, Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in this Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

A signed original of this written statement required by Section 906 has been provided to Minefinders Corporation Ltd. and will be retained by Minefinders Corporation Ltd. and furnished to the Securities and Exchange Commission or its staff upon request.