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. 1,916,869,262report 1,988,916,837 ordinary shares, par value 0.10 Russian rubles each and 155,479,301388,698,252 American Depositary Shares as of December 31, 2009.2011.

            Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ý Yes    o No

            If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.o Yesý No

            Note—Checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 from their obligations under those Sections.

            Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 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.ý Yeso 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) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes:ý    No:o

            Indicate by check mark whether the registrant is a large accelerated filer, an accelerated file, or a non-accelerated filer. See definition of "accelerated filer and large accelerated filer" in Rule 12b-2 of the Exchange Act. (Check One):

            Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing:

            If "Other" has been checked in response to the previous question indicate by check mark which financial statement item the registrant has elected to follow.o Item 17    o Item 18

            If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).o Yes    ý No

(1)

Listed, not for trading or quotation purposes, but only in connection with the registration of ADSs pursuant to the requirements of the Securities and Exchange Commission.

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        Unless otherwise indicated or unless the context requires otherwise, references in this document to (i) "MTS," "the Group," "we," "us," or "our" refer to Mobile TeleSystems OJSC and its subsidiaries; (ii) "MTS-Ukraine" or "UMC" are"MTS Ukraine" is to MTS Ukraine Private Joint Stock Company (formerly CJSC Ukrainian Mobile Communications,Communications), our Ukrainian subsidiary; (iii) "MTS-Uzbekistan" areis to Uzdunrobita, our Uzbekistan subsidiary; (iv) "MTS-Turkmenistan" and "BCTI" are to BCTI,Barash Communication Technologies, Inc., our Turkmenistan subsidiary; (v) "Comstar" or "Comstar UTS""Comstar-UTS" are to COMSTAR—United TeleSystems, our fixed line subsidiary; andsubsidiary, which was merged into us in 2011; (vi) "MGTS" areis to Moscow City Telephone Network, our Moscow PSDNpublic switched telephone network ("PSTN") fixed line subsidiary.subsidiary; and (vii) "K-Telecom" or "VivaCell-MTS" are to K-Telecom CJSC, our Armenian subsidiary; and (viii) "Sistema" is to Joint-Stock Financial Corporation Sistema, our majority shareholder. We refer to Mobile TeleSystems LLC, our 49% owned joint ventureequity investee in Belarus, as "MTS Belarus." As MTS Belarus is an equity investee, our revenues and subscriber data do not include MTS Belarus. Our reporting currency is the U.S. dollar and we prepare our consolidated financial statements in accordance with accounting principles generally accepted in the United States or ("U.S. GAAP.GAAP").

        In this document, references to "U.S. dollars," "dollars," "$" or "USD" are to the lawful currency of the United States, "rubles" or "RUR""RUB" are to the lawful currency of the Russian Federation, "hryvnias" are to the lawful currency of Ukraine, "soms" are to the lawful currency of Uzbekistan, "manats" are to the lawful currency of Turkmenistan, "drams""dram" are to the lawful currency of Armenia and "€," "euro" or "EUR" are to the lawful currency of the member states of the European Union that adopted a single currency in accordance with the Treaty of Rome establishing the European Economic Community, as amended by the treaty on the European Union, signed at Maastricht on February 7, 1992. References in this document to "shares" or "ordinary shares" refers to our ordinary shares, "ADSs" refers to our American depositary shares, each of which represents fivetwo ordinary shares, and "ADRs" refers to the American depositary receipts that evidence our ADSs. Prior to May 3, 2010, each ADS represented five ordinary shares of our common stock. "CIS" refers to the Commonwealth of Independent States.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        Matters discussed in this document may constitute forward-looking statements within the meaning of Section 27A of the U.S. Securities Act of 1933 or the U.S.(the "U.S. Securities Act,Act"), and Section 21E of the U.S. Securities Exchange Act of 1934 or the U.S.(the "U.S. Exchange Act.Act"). The Private Securities Litigation Reform Act of 1995 provides safe harbor protections for forward-looking statements in order to encourage companies to provide prospective information about their businesses. Forward-looking statements include statements concerning plans, objectives, goals, strategies, future events or performance, and underlying assumptions and other statements, which are other than statements of historical facts.

        Mobile TeleSystems OJSC, or        MTS desires to take advantage of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995 and is including this cautionary statement in connection with this safe harbor legislation and other relevant law. This document and any other written or oral statements made by us or on our behalf may include forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our financial condition, results of operations, business strategy and financial needs. The words "believe," "expect," "anticipate," "intend," "estimate," "forecast," "project," "predict," "plan," "may," "should," "could" and similar expressions identify forward-looking statements. Forward-looking statements appear in a number of places including, without limitation, "Item 3. Key Information—D. Risk Factors," "Item 4. Information on Our Company—B. Business Overview," "Item 5. Operating and Financial Review and Prospects," and "Item 11. Quantitative and Qualitative Disclosures about Market Risk" and include statements regarding:

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our strategies, future plans, economic outlook, industry trends and potential for future growth;



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our liquidity, capital resources and capital expenditures;



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our payment of dividends;



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our capital structure, including our indebtedness amounts;



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our ability to generate sufficient cash flow to meet our debt service obligations;



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our ability to achieve the anticipated levels of profitability;



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our ability to timely develop and introduce new products and services;



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our ability to obtain and maintain interconnect agreements;



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our ability to secure the necessary spectrum and network infrastructure equipment;



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our ability to meet license requirements and to obtain and maintain licenses and regulatory approvals;



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our ability to maintain adequate customer care and to manage our churn rate; and



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our ability to manage our rapid growth and train additional personnel.

        The forward lookingforward-looking statements in this document are based upon various assumptions, many of which are based, in turn, upon further assumptions, including without limitation, management's examination of historical operating trends, data contained in our records and other data available from third parties. Although we believe that these assumptions were reasonable when made, because these assumptions are inherently subject to significant uncertainties and contingencies which are difficult or impossible to predict and are beyond our control, we cannot assure you that we will achieve or accomplish these expectations, beliefs or projections. In addition to these important factors and matters

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discussed elsewhere herein, important factors that, in our view, could cause actual results to differ materially from those discussed in the forward-looking statements include:

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growth in demand for our services;



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changes in consumer preferences or demand for our products;



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availability of external financing on commercially acceptable terms;



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the developments of our markets;



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the highly competitive nature of our industry and changes to our business resulting from increased competition;



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the impact of regulatory initiatives;



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the rapid technological changes in our industry;



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cost and synergy of our recent acquisitions;



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the acceptance of new products and services by customers;



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the condition of the economies of Russia, Ukraine and certain other countries of the CIS;



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risks relating to legislation, regulation and taxation in Russia and certain other CIS countries, including laws, regulations, decrees and decisions governing each of the telecommunications industries in the countries where we operate, currency and exchange controls relating to entities in Russia and other countries where we operate and taxation legislation relating to entities in Russia and other countries where we operate, and their official interpretation by governmental and other regulatory bodies and by the courts of Russia and the CIS;



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political stability in Russia, Ukraine and certain other CIS countries; and



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the impact of general business and global economic conditions and other important factors described herein and from time to time in the reports filed by us with the U.S. Securities and Exchange Commission or the SEC.(the "SEC").

        All future written and verbal forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section. New risks and uncertainties arise from time to time, and it is impossible for us to predict these events or how they may affect us. Readers are cautioned not to place undue reliance on these forward-looking statements. Except to the extent required by law, neither we, nor any of our respective agents, employees or advisors intends or has any duty or obligation to supplement, amend, update or revise any of the forward-looking statements contained or incorporated by reference in this document.

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PART I

Item 1.    Identity of Directors, Senior Management and Advisors

        Not applicable.

Item 2.    Offer Statistics and Expected Timetable

        Not applicable.

Item 3.    Key Information

A.  Selected Financial Data

        The selected consolidated financial data for the years ended December 31, 2007, 20082009, 2010 and 2009,2011, and as of December 31, 20082009, 2010 and 2009,2011, are derived from the audited consolidated financial statements, prepared in accordance with U.S. GAAP included elsewhere in this document. In addition, the following table presents unaudited selected consolidated financial data derived from our consolidated statement of financial position as of December 31, 2007. Our results of operations are affected by acquisitions. Results of operations of acquired businesses are included in our audited consolidated financial statements from their respective dates of acquisition, other than with respect to our acquisition of Comstar,certain subsidiaries of Sistema, as further described below.

        In October 2009, we acquired a 50.91% stake in Comstar, a provider of fixed line communication services in Russia, Ukraine and Armenia, from Sistema for RUB 39.15 billion rubles ($1.32 billion as of October 12, 2009). We subsequently increased our ownership stake in Comstar to 61.97% (or 64.03% excluding treasury shares) in December 2009.2009 and to 70.97% in September 2010 through a voluntary tender offer. On December 23, 2010, the extraordinary general meetings of shareholders of Comstar and MTS approved a merger of Comstar and us. On March 10, 2011, we completed a share buyback as part of the reorganization of MTS and on April 1, 2011 the merger was completed. A total of 8,000 MTS ordinary shares representing 0.0004% of our issued share capital were repurchased in the buyback for RUB 1.96 million ($70,000 as of March 31, 2011). The buyback price was set at RUB 245.19 ($8.62 as of March 31, 2011) per one MTS ordinary share. In addition, a total of 22,483,791 Comstar ordinary shares representing 5.38% of the Comstar issued share capital were repurchased for RUB 4.8 billion ($168.3 million as of March 31, 2011). The buyback price was set at RUB 212.85 ($7.49 as of March 31, 2011) per one Comstar ordinary share. The remaining 98,853,996 Comstar ordinary shares were converted into MTS ordinary shares at an exchange ratio of 0.825 MTS ordinary shares for each Comstar ordinary share. See "Item 5. Operating and Financial Review and Prospects—A. Operating Results—Certain Factors Affecting our Financial Position and Results of Operations—Acquisitions."

        In August 2010, we acquired a 95% ownership interest in Metro-Telecom, a company which owns a fiber optic network located in the Moscow metro, from Invest-Svyaz CJSC, a wholly owned subsidiary of Sistema, for RUB 339.35 million ($11.01 million as of August 27, 2010).

        In June 2010, we acquired a 15% ownership interest in TS-Retail OJSC ("TS-Retail") from Sistema for one US dollar consequently increasing our effective ownership interest in TS-Retail to 49.6%. We subsequently increased our effective ownership interest in TS-Retail to 50.95%, which was achieved through a voluntary tender offer to purchase Comstar's shares in September 2010.

        In December 2010, we acquired a 100% ownership stake in Sistema Telecom, a subsidiary of Sistema which owns the egg-shaped logos each of the telecommunications companies operating within the Sistema group uses, including us, and a 45% ownership stake in TS-Retail, from Sistema for RUB 11.59 billion ($378.98 million as of December 27, 2010). As a result of this acquisition and the completion of our merger with Comstar on April 1, 2011, we currently own a 100% stake in TS-Retail.

        As we, Comstar, TS-Retail, Sistema Telecom and ComstarMetro-Telecom were under the common control of Sistema, our acquisition of a majority stakestakes in Comstarthese companies has been treated as a combination of entities under common control and accounted for in a manner similar to a pooling-of-interests,i.e., the assets and liabilities acquired were recorded at their historical carrying value and the consolidated

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our competitors will not offer similar services at lower prices; and



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changes in governmental policies, rules, regulations or practices will not affect our network rollout or our business operations.

        See also "—If we cannot successfully develop our network, we will be unable to expand our subscriber base and maintain our profitability."

        In addition, Russian military authorities also use frequencies onof the 3G spectrum, which may limit the availability of 3G frequencies for commercial use in certain areas. During the construction of our 3G network, there is also a risk that the frequencies assigned to us for commercial use may overlap with frequencies used by the Russian military. For example, conflicts over the availability of frequency long reserved for military use in Moscow caused delay in the commercial launch of 3G services in Moscow by all of the 3G license holders, although some of these frequencies were releasedcleared for commercial use in 2009. If additional overlap were to occur, it could cause problems or delays in the development and operation of our 3G network in Russia.

        We may also face competition from operators using second generation or 2G,("2G") or other forms of 3G technology. For example, licenses for the use of CDMA technology have already been granted for the provision of fixed wireless services in a number of regions throughout Russia. CDMA is a 2G digital cellular telephony technology that can be used for the provision of both wireless and fixed services. Currently, CDMA technology is offered by certain mobile operators in Russia who operate using the Nordic Mobile Telephone 450 MHz or NMT-450,("NMT-450") standard. If CDMA operators were able to develop widespread networks throughout Russia, we would face increased competition.

        In addition, the development of WiMAXWi-Max networks will likely pose additional competition for 3G providers operating in the IMT-2000/UMTS standard. The Russian government also recently held a tendertenders for the issuance of 4G licenses to operate 4G networks infor 40 Russian regions throughout Russia.(in the 2.3-2.4 GHz frequency band). Fourth-generation wireless services are expected to provide faster, higher quality data transfer and streaming capabilities as compared to 2G and 3G and may pose additional competition for 3G providers. Rostelecom won the tender for 3839 of the 40 4G licenses (in the 2.3-2.4 GHz frequency band) in February-March 2010 and will be requiredin November 2011 received permission from the Ministry of Defense to build its network and commence operation within 18 months.

Tableuse the allotted frequencies for the creation of Contentsa 4G network.

        Potential competition from other 3G, CDMA, WiMAXWi-Max and 4G providers, together with any substantial problem with the rollout of our 3G network and provision of 3G services in the future, could materially adversely affect our business, financial condition and results of operations.

If we are unable to successfully develop and/or deploy 4G wireless services in Russia or one of the operators in the market obtains significant technological and/or commercial advantage over us in 4G wireless services, it may have a material adverse effect on our business and results of operations in the long term.

        The next step in the development of Russian telecommunications is the deployment of 4G/LTE networks. The cost of 4G/LTE network development and quality of services (data speed, quality of coverage) depend on the band and the width of frequency range given to an operator.

        In September 2011, the Russian government announced its intention to auction frequencies for LTE use on a national level in 2012. Additionally, the State Radio Frequencies Commission gave Scartel (Yota brand) two ranges of LTE frequencies, 30 MHz each, in the 2.5-2.7 GHz band for use on the whole territory of Russia in exchange for 4G frequencies held by Scartel for Wi-Max technology of total width of 70MHz (the exchange was completed on a non-auction basis). Four sets of frequencies in the 791-862 MHz band are planned to be sold during the auction in 2012, after which the winners of the frequencies will also receive frequencies in the 2.5-2.7 GHz band. The remaining frequencies that are to be sold during the auction comprise 40 MHz of the 2.5-2.7 GHz band. Therefore, other

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operators may receive frequency ranges much later than Scartel and the ranges they receive may be much smaller than those given to Scartel.

        Initially it was planned that all operators would receive equal access to the Scartel infrastructure, which would allow each operator to reduce its 4G/LTE network development costs. In March 2011, we, MegaFon, Vimpelcom and Rostelecom signed a non-binding memorandum of understanding with Scartel, according to which we, MegaFon, Vimpelcom and Rostelecom were to receive access to Scartel's 4G network infrastructure (which was to be built) and were to receive options to purchase shares in Scartel in 2014 at a price determined by an independent appraisal. MTS considered a preliminary value assessment of Scartel to be unduly high. Currently, we are still considering our further actions in regards to this arrangement.

        According to recent news reports, Megafon is negotiating a possible acquisition of Scartel. If this transaction takes place, Megafon may obtain significant short term competitive advantage both in terms of frequency resources and LTE network development costs.

        Furthermore, the limited number of available frequencies may prevent us from realizing the full benefits we expect to receive from the development of a 4G network, because our network capacity would be constrained and our ability to expand limited. Moreover, if we cannot develop a commercially viable 4G network, and one of our competitors does, that competitor would have an advantage over us, which in turn may have a material adverse effect on our business.

Our inability to obtain a UMTS license in Ukraine on commercially reasonable terms, or at all, may negatively affect our competitive position in Ukraine.

        In September 2009, the NCRC announced plans to launch a tender for a single 3G/UMTS mobile services license in Ukraine with the starting price set at 400 million hryvnia (equivalent to $50.1 million at December 31, 2009). However, the NCRC canceled the planned tender in November 2009 following a decision by the President of Ukraine to put the tender and conversion of the radio frequencies on hold. Following the election of Viktor Yanukovich as Ukraine's new President in February 2010, further steps toward a tender for one or morea 3G/UMTS licenseslicense in Ukraine areis expected althoughin 2012 after the timing and terms are not yet clear.planned sale of Trimob. See also "—Governmental regulation of our interconnect rates in Ukraine could adversely affect our results of operations."

        Our ability to prevail in a tender for a 3G/UMTS license in Ukraine may require us to pay a significant amount for the license as well as incur significant costs in building out the 3G network, and we may not be able to recoup these costs through our service revenues. Specifically, the Ministry of Defense of Ukraine indicated in 2010 that the cost of conversion of the radio frequencies required to establish a 3G/UMTS network would be equal to 2.5 billion hryvnia. That same year, as a result of discussions between the government and the telecommunications operators, it was concluded that the justifiable market price of conversion of the radio frequencies is 600 million hryvnia. However, in the beginning of 2011, the head of the Administration of State Service on Special Communications and Information Protection of Ukraine stated that the conversion of a narrow range of radio frequencies would cost 2.5 billion hryvnia.

        To date, the Ministry of Defense of Ukraine has not adopted a radio frequencies conversion plan or indicated when they plan to do so and, therefore, the tender for a 3G/UMTS license in Ukraine has still not occurred. If we do not obtain a 3G/UMTS license, the award of the license to one of our competitors would increase the competition we face in the provision of both GSM and 3G services in Ukraine and inhibit our expansion efforts. Either of the foregoing may have a material adverse effect on our business, financial condition, results of operations and prospects.

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Service disruptions on our networks could lead to a loss of subscribers, damage to our reputation, violations of the terms of our licenses and subscriber contracts and penalties.

        We are able to deliver services only to the extent that we can protect our network systems against damage from communications failures, computer viruses, power failures, natural disasters and unauthorized access. Any system failure, accident or security breach that causes interruptions in our operations could impair our ability to provide services to our customers and materially adversely affect our business and results of operations. In addition, to the extent that any disruption or security breach results in a loss of or damage to customers' data or applications, or inappropriate disclosure of confidential information, we may incur liability as a result, including costs to remedy the damage caused by these disruptions or security breaches.

        While we maintain back-up systems for our telecommunications equipment, network management, operations and maintenance systems, these systems may not ensure recovery in the event of a network failure. In particular, in the event of extensive software and/or hardware failures, significant disruptions to our systems could occur, leading to our inability to provide services. Disruptions in our provision of services could lead to a loss of subscribers, damage to our reputation, violations of the terms of our licenses and subscriber contracts and penalties.

        Our computer and communications hardware is protected through physical and software safeguards. However, it is still vulnerable to fire, storm, flood, loss of power, telecommunications failures, interconnectioninterconnect failures, physical or software break-ins, viruses and similar events. Although our computer and communications hardware is insured against fires, storms and floods, we do not carry business interruption insurance to protect us in the event of a catastrophe, even though such an event could have a material adverse effect on our business.

Failure to fulfill the terms of our licenses could result in their suspension or termination, which could have a material adverse effect on our business and results of operations.

        Each of our mobile licenses requires service to be offered by a specific date and some contain further requirements as to network capacity and territorial coverage to be reached by specified dates.

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In addition, all of our mobile licenses require us to comply with various telecommunications regulations relating to the use of radio frequencies and numbering capacity allocated to us, network construction and interconnectioninterconnect rules, among others. The license requirements applicable to our fixed line businesses include participation in a federal communications network, adherence to technical standards, investment in network infrastructure, employment of Russian technical personnel and the provision of certain services to the federal government and PSTN subscribers at regulated tariffs, among others. If we fail to comply with the requirements of Russian, Ukrainian or other applicable legislation or we fail to meet any terms of our licenses, our licenses and other authorizations necessary for our operations may be suspended or terminated. In addition to the impact on our operations, the suspension or loss of certain licenses could also cause an event of default under certain of our debt obligations. A suspension or termination of our licenses or other necessary governmental authorizations could therefore have a material adverse effect on our business and results of operations.

Failure to renew our licenses or receive renewed or new licenses with similar terms to our existing licenses could have a material adverse effect on our business and results of operations.

        Our telecommunications licenses expire in various years from 20102012 to 2021.2022. These licenses may be renewed upon application to the relevant governmental authorities. Government officials in Russia and the other CIS countries in which we operate have broad discretion in deciding whether to renew a license, and may not renew licenses after their expiration. If licenses are renewed, theyLicense renewals may be renewed withsubject to additional obligations, includingconditions, such as revenue sharing or the mandatory modernization of our network. These and similar conditions would constitute indirect payment obligations.

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        In addition, we may be subject to penalties or our licenses may be suspended or terminated for non-compliance with the new licenses requirements. The suspension or loss of certain licenses could significantly limit our operations and cause certain of our debt to be accelerated.

        Failure to renew our telecommunications licenses or receive renewed or new licenses with similar terms to existing licenses could significantly limit our operations, which could have a material adverse effect on our business and results of operations.

If frequencies currently assigned to us are reassigned to other users or if we fail to obtain renewals of our frequency allocations, our network capacity will be constrained and our ability to expand limited, resulting in a loss of market share and lower revenues.

        There is a limited number of frequencies available for wireless operators in each of the regions in which we operate or hold licenses to operate. We are dependent on access to adequate spectrum allocation in each market in which we operate in order to maintain and expand our subscriber base. If frequencies are not allocated to us in the future in the quantities, with the geographic span and for time periods that would allow us to provide wireless services on a commercially feasible basis throughout all of our license areas, our business, financial condition, results of operations and prospects may be materially adversely affected.

        A loss of allocated spectrum, which is not replaced by other adequate allocations, could also have a substantial adverse impact on our network capacity. In addition, frequency allocations are often issued for periods that are shorter than the terms of the licenses, and such allocations may not be renewed in a timely manner or at all. If our frequencies are revoked or we are unable to renew our frequency allocations, our network capacity would be constrained and our ability to expand limited, resulting in a loss of market share and lower revenues.

        We have in the past been unable to obtain certain requested frequency allocations. For example, our applicationtender bid in Ukraine for additional frequencies foron the CDMA-450 spectrum was denied in March 2010. If2010 as we were the only applicant in the tender process. In the near term, available CDMA-450 frequency spectrum capacity combined with network optimization measures undertaken by us is sufficient to support existing and potential demand for CDMA services, and generally we consider UMTS frequencies to be a bigger strategic priority than CDMA. However, if in the future we are not allocated the requested CDMA frequencies, our ability to expand CDMA-450 services in Ukraine may be hindered.

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An increase in the fees for frequency spectrum usage could have a negative effect on our financial results.

        The terms of our licenses in Russia and the CIS require that we make payments for frequency spectrum usage. Any significant increase in the fees payable for the frequency channels that we use or additional frequency channels that we need in Russia or the CIS could have a negative effect on our financial results. For example, new rules on the calculation of fees for frequency spectrum usage in Russia effective as of January 1, 2012 will lead to the increase of the fees we pay for frequency spectrum usage by 40-45% in 2012 as compared to 2011. Similarly, in April 2010, the Cabinet of Ministers of Ukraine significantly increased the amount of paymentfees for frequency spectrum usage in Ukraine for cellular communications. Furthermore, according to the Tax Code of Ukraine, the fees payable for frequency usage shall be determined based in part on the rate of inflation and reviewed annually effective January 1, 2011. Accordingly, the fees for frequency usage were increased by 9.4% in 2011 as compared to 2010, and by 8.9% in 2012 as compared to 2011.

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If we are unable to maintain our favorable brand image, we may be unable to attract new subscribers and retain existing subscribers, leading to loss of market share and revenues.

        Developing and maintaining awareness of our brands is critical to informing and educating the public about our current and future services and is an important element in attracting new subscribers. We believe that the importance of brand recognition is increasing as our markets become more competitive. Successful promotion of our brands will depend largely on the effectiveness of our marketing efforts and on our ability to provide reliable and useful products and services at competitive prices. Brand promotion activities may not yield increased operating revenues, and even if they do, such operating revenues may not offset the operating expenses we incur in building our brands. Furthermore, our ability to attract new subscribers and retain existing subscribers depends, in part, on our ability to maintain what we believe to be our favorable brand image. Negative publicity or rumors regarding our company, our shareholders and affiliates or our services could negatively affect this brand image, which could lead to loss of market share and revenues. Our failure to successfully and efficiently promote and maintain our brands may limit our ability to attract new subscribers and retain our existing subscribers and materially adversely affect our business and results of operations.

We engage in transactions with related parties, which may present conflicts of interest, potentially resulting in the conclusion of transactions on terms not determined by market forces.

        We have purchased interests in various mobile telecommunications companies from Sistema and entered into arrangements with subsidiaries and affiliates of Sistema for the provision of advertising services (Open Joint Stock Company Advertising Agency Maxima or Maxima,("Maxima"), and Closed Joint Stock Company Mediaplanning or Mediaplanning)("Mediaplanning"), IT services and hardware purchases (LLC Kvazar-Micro.RU, or Kvazar)Sitronics IT and Private Joint Stock Company Sitronics IT Ukraine), banking services (Moscow(MTS Bank, formerly Moscow Bank of Reconstruction and Development or MBRD)("MBRD")), telephone network services (MGTS), leasing of office space (MGTS) and the purchase of a new billing system (Open Joint Stock Company Sitronics), among others. Related party transactions with Sistema and other companies within the Sistema group may present conflicts of interest, potentially resulting in the conclusion of transactions on terms less favorable than could be obtained in arm's-length transactions.not determined by market forces. See "Item 7. Major Shareholders and Related Party Transactions—B. Related Party Transactions."

In the event that our minority shareholders or the minority shareholders of our subsidiaries were to successfully challenge past or future interested party transactions, or do not approve interested party transactions or other matters in the future, we could be limited in our operational flexibility and our business, financial condition, results of operations and prospects could be materially adversely affected.

        We own less than 100% of the equity interests in some of our subsidiaries. In addition, certain of our wholly owned subsidiaries have had other shareholders in the past. We and our subsidiaries in the past have carried out, and continue to carry out, transactions that may be considered to be "interested party transactions" under Russian law, requiring approval by disinterested directors, disinterested independent directors or disinterested shareholders depending on the nature of the transaction and parties involved. The provisions of Russian law defining which transactions must be approved as "interested party transactions" are subject to different interpretations and, as a result, it is possible that our and our subsidiaries' interpretation and application of these provisions could be subject to challenge. Any such challenges, if successful, could result in the invalidation of transactions, which

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could have a material adverse effect on our business, financial condition, results of operations and prospects.

        In addition, Russian law requires a three-quarters majority vote of the holders of voting stock present at a shareholders' meeting to approve certain transactions and other matters, including, for example, charter amendments, major transactions involving assets in excess of 50% of the assets of the company, repurchase of shares by the company and certain share issuances. In some cases, minority

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shareholders may not approve interested party transactions requiring their approval or other matters requiring minority shareholder or supermajority approval. In the event that these minority shareholders were to successfully challenge past interested party transactions, or do not approve interested party transactions or other matters in the future, we could be limited in our operational flexibility and our business, financial condition, results of operations and prospects could be materially adversely affected.

Our competitive position and future prospects depend on our senior managers and other key personnel.personnel and our ability to attract, retain and motivate qualified key personnel could have a material adverse effect on our business, financial condition and results of operations.

        Our ability to maintain our competitive position and to implement our business strategy is dependent to a large degree on the services of our senior management team and other key personnel. Moreover, competition in Russia and in the other countries where we operate for personnel with relevant expertise is intense due to the relatively small number of qualified individuals. As a result, we attempt to structure our compensation packages in a manner consistent with the evolving standards of the labor markets in these countries. We are not insured against the detrimental effects to our business resulting from the loss or dismissal of our key personnel. In addition, it is not common practice in Russia and the other countries where we operate to purchase key-man life insurance policies, and we do not carry such policies for our senior management and other key personnel. The loss or decline in services of members of our senior management team or an inability to attract, retain and motivate qualified key personnel could have a material adverse effect on our business, financial condition and results of operations.

In the event that deficiencies or ambiguities in privatization legislation are exploited to challenge our ownership in our privatized subsidiaries and we are unable to defeat these challenges, we risk losing our ownership interests in our subsidiaries or their assets, which could materially adversely affect our business, financial condition and results of operations.

        Through our acquisition of a controlling stake in Comstar, we gained a controlling stake in its subsidiary, MGTS, the incumbent PSTN operator in Moscow, and our business strategy may involve the acquisition of additional privatized companies. To the extent that privatization legislation is vague, inconsistent or in conflict with other legislation, including conflicts between federal and local privatization legislation, many privatizations are vulnerable to challenge, including selective challenges. For instance, a series of presidential decrees issued in 1991 and 1992 that granted to the Moscow City government the right to adopt its own privatization procedures were subsequently held to be invalid by the Constitutional Court of the Russian Federation, which ruled, in part, that the presidential decrees addressed issues that were the subject of federal law. While this court ruling, in theory, did not require any implementing actions, the presidential decrees were not officially annulled by another presidential decree until 2000.

        Sistema won a privatization tender for MGTS in April 1995 and was issued 25% of MGTS' share capital. As part of its tender obligations, Sistema committed to invest approximately $106 million in MGTS over a three-year period in exchange for the right to purchase an additional issue of MGTS' ordinary shares. In 1998, upon satisfying its tender obligations, Sistema exercised this right and increased its stake to 50% of MGTS' share capital. At the time Sistema took possession of this interest, there were press reports that certain minority shareholders of MGTS had filed complaints with the prosecutor's office and the Federal Commission on the Securities Market (currently the FSFM)Federal Service for Financial Markets ("FSFM")) objecting to the share issuance. In addition, certain members of the Russian parliament requested the

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Audit Chamber of the Russian Federation and other governmental agencies to investigate whether there was compliance with the relevant rules and regulations governing MGTS' privatization. Although no formal action or claim against MGTS or its shareholders was ever made by any governmental entity, in the event that any of our privatized companies are subject to challenge in the future as having been improperly privatized and we are unable to defeat this claim, we

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risk losing our ownership interest in the company or its assets, which could materially adversely affect our business, financial condition and results of operations.

        In addition, under Russian law, transactions in shares may be invalidated on many grounds, including a sale of shares by a person without the right to dispose of such shares, breach of interested party and/or major transactions rules and failure to register the share transfer in the securities register. As a result, defects in earlier transactions in shares of our subsidiaries (where such shares were acquired from third parties) may cause our title to such shares to be subject to challenge. While Russian law provides for a three year statute of limitations for challenging private merger and acquisition transactions, there is no statute of limitations for challenging privatizations.

The entry of Mobile Virtual Network Operatorsmobile virtual network operators into the Russian mobile communications market could increase competition and subscriber churn, resulting in a loss of our market share and decreased revenue.

        On December 29, 2008, the Ministry of Communications and Mass Media adopted an order establishing the requirements for Mobile Virtual Network Operators, or MVNOs.mobile virtual network operators ("MVNOs"). MVNOs are companies that provide mobile communications services but do not own the radio frequencies and, often, the network infrastructure required to do so. According to the order, MVNOs in Russia must be licensed, and their use of frequencies and infrastructure and rendering of services will be done pursuant to agreements entered into between MVNOs and existing frequency holders. There is no requirement that existing frequency holders transact with the MVNOs, and agreements between them will be entered into at their option.

        The aim of the Ministry in establishing the legal framework for MVNOs to operate is to increase competition in the Russian mobile services market, which is currently dominated by us, Vimpelcom and MegaFon. While existing frequency holders, including us, may receive revenues from MVNOs for the use of our frequencies and network infrastructure, we expect these revenues to be lower than the revenues we would receive if providing services directly to subscribers. In addition, in the event we lose subscribers to MVNOs that lease their frequencies and infrastructure from an operator other than us, we will be deprived of the revenue streams from both the subscribers and the MVNOs. The MVNOs may also establish aggressive tariffs, which could result in increased subscriber churn and/or driving down the tariffs of all mobile operators.

        To date, nineIn March 2011, Sky Link and CountryCom, a Moscow based telecommunications company, announced that together they would launch MVNO licenses have been issuedservices in Russia, although none of the Moscow region which will be based on frequencies and infrastructure owned by Sky Link and CountryCom would be responsible for billing and other customer-related services. In September 2010, Sky Link also launched an MVNO license holders have commenced operations. We areproject with Center Telecom, a regional fixed-line telecommunications company which has merged into Rostelecom, under the Domolink brand which is currently in discussions withlimited to Internet services. In August 2010, we launched a leading Russian retail chain regarding the potential launch of an MVNO.tariff plan under a separate brand name through X5 Retail group as a pseudo-MVNO. In addition, MegaFon recently launched a new tariff plan under a separate brand name as a pseudo-MVNO.

        In December 2011, Scartel reached an agreement with MegaFon and Rostelecom to allow them to provide LTE services through Scartel's network in exchange for permitting Scartel to use the two companies' network infrastructure. In February 2012, Scartel and MegaFon received the necessary licenses to allow MegaFon to provide such services over the Scartel LTE network.

        While the impact of MVNOs' entry into the Russian mobile communications market is not yet clear, the emergence of any of the foregoing trends could increase market competition and subscriber churn and, as a result, have a material adverse effect on our business, financial condition, results of operations and prospects.

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A finding by the Federal Antimonopoly ServiceFAS that we have acted in contravention of antimonopoly legislation could have a material adverse affecteffect on our business, financial condition and results of operation.

        Our businesses have grown substantially through the acquisition and formation of companies, many of which required the prior approval of, or subsequent notification to, FAS or its predecessor agencies. In part, relevant legislation in certain cases restricts the acquisition or formation of companies by groups of companies or individuals acting in concert without such prior approval or notification. While

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we believe that we have complied with the applicable legislation for our acquisitions and formation of new companies, this legislation is sometimes vague and subject to varying interpretations. If FAS were to conclude that our acquisition or formation of a new company was done in contravention of applicable legislation, it could impose administrative sanctions and require the divestiture of such company or other assets, which could have a material adverse effect on our business, financial condition and results of operations.

        In addition, in MarchOctober 2010, FAS commenced proceedings against us,found that we, Vimpelcom and MegaFon alleging violations ofviolated antimonopoly laws on competition relating to our pricing for roaming services. As a result, FAS imposed an administrative fine on us in the amount of RUR 21.9 million which represents 1.0% of the revenues we derived from roaming services in CIS countries in 2009. We paid the fine imposed on us by FAS on March 28, 2011. See also "Item 8. Financial Information—A. Consolidated Statements and Other Financial Information—7. Litigation."

        In addition, in October 2011, FAS began an investigation of our and Vimpelcom's actions, suspecting violation of antimonopoly laws by coordinated pricing of iPhone 4 handsets. The investigation is currently in progress. Although we believe that we have not violated the law,antimonopoly laws, we could be liable for fines of up to 15% of the revenues we derived from roaming services in 2009iPhone 4 sales if a violation is found.

A finding by the AMC that we have acted in contravention of antimonopoly legislation could have a material adverse effect on our business, financial condition and results of operation.

        In December 2011, the AMC opened an investigation into whether MTS Ukraine violated antimonopoly legislation with its pricing of international roaming services. The AMC stated that the average price of international roaming services offered by MTS Ukraine and its roaming partners is higher than the corresponding prices in the European Union, which may demonstrate that the prices charged by MTS Ukraine are not economically justified. The investigation will examine whether MTS Ukraine used its dominant position in the Ukrainian telecommunications market to establish prices that would not be possible if there was significant competition on the telecommunications market. Although we believe that we did not violate antimonopoly laws, we could be liable for up to 10% of MTS Ukraine revenues. We plan to submit our arguments to the AMC regarding the matter of this investigation. However, the AMC may determine that we violated antimonopoly legislation in this or other matters, and may impose fines on us, which may have a material adverse effect on our business, financial condition and results of operation. In addition, we may be required to adjust the prices that we charge for international roaming services, which may adversely affect our revenues. See also "—Governmental regulation of our interconnect rates in Ukraine could adversely affect our results of operations" and "Item 8. Financial Information—A. Consolidated Statements4. Information on Our Company—B. Business Overview—Regulation of Telecommunications in the Russian Federation and Other Financial Information—7. Litigation.Ukraine—Regulation in Ukraine—Competition" for additional information."

If we are found to have a dominant position in the markets where we operate, the government may regulate our subscriber tariffs and restrict our operations.

        Under Russian legislation, FAS may categorize a company controlling between 35%-50% or over 50% of a market or otherwise able to control market conditions as a dominant force in such market. Moreover, recent amendments to Russian antimonopoly regulations made it possible that any three

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companies collectively holding a market share of over 50% or five companies collectively holding a market share of over 70%, and in each case over 8% individually, can be found to have a dominant position on a certain market. Companies controlling over 35% or otherwise occupying a dominant position on the market are listed by FAS in a special register and may become subject to monitoring and reporting requirements with respect to such markets. Current Russian legislation does not clearly define "market" in terms of the types of services or the geographic area. One of our subsidiaries, MGTS, is categorized by the Federal Tariff Service as a natural monopoly in the Moscow telecommunications market. As a result, MGTS' tariffs are subject to regulation by the Federal Tariff Service. See "—ComstarWe and MGTS are subject to extensive regulation of theirour respective tariffs, and these tariffs may not fully compensate us for the cost of providing required services."

        We were also categorized by FAS as a company with a market share exceeding 35% in the mobile communications market in Moscow and the Moscow region, Ivanovo region, Arkhangelsk region, Magadan region, Omsk region, andSakhalin region, Nenets Autonomous District.District and Udmurt Republic. In the event that we are found in the future to have a dominant position on these or any additional markets, the Federal Tariff ServiceFAS would have the right to impose certain restrictions provided for under the antimonopoly laws, including a mandated reduction in our tariffs, and FAS would have the right to impose certain restrictions on our operations in such markets. See "Item 4. Information on Our Company—B. Business Overview—Regulation of Telecommunications in the Russian Federation and Ukraine—Regulation in the Russian Federation—Competition, InterconnectionInterconnect and Pricing" for additional information."

        Additionally, MTS-Ukraine, which according to AC&M-Consulting had a 31.8% market share of the Ukrainian wireless communications market as of December 31, 2009, can beMTS Ukraine, was categorized as a company with a dominant position in the telecommunications market and therefore could becomeis subject to certain government imposed restrictions. While MTS-Ukraine has not, as atrestrictions, including limitations on the dateinterconnect rates it can charge other operators. See "—Governmental regulation of this document, been categorized as a company with a dominant positionour interconnect rates in the market, it reduced certainUkraine could adversely affect our results of its tariffs at the recommendation of the AMC in April 2004. Seeoperations" and "Item 4. Information on Our Company—B. Business Overview—Regulation of Telecommunications in the Russian Federation and Ukraine—Regulation in Ukraine—Competition" for additional information.

        If we or any of our subsidiaries were to be classified by FAS (or the AMC with respect to our operations in Ukraine) as a dominant market force or as having a dominant position in the market, FAS and the Federal Tariff Service (or the AMC, as the case may be) would have the power to impose certain restrictions on our or their businesses. In particular, the authorities may impose on us tariffs at levels that could be competitively disadvantageous and/or set interconnect rates between operators that may adversely affect our revenues. Moreover, our refusal to adjust our tariffs according to such government-determined rates could result in the imposition of fines. Additionally, geographic

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restrictions on our expansion could reduce our subscriber base and prevent us from fully implementing our business strategy.

Comstar and MGTS are subject to extensive regulation of their tariffs, and these tariffsstrategy, which may not fully compensate us for the cost of providing required services.

        As the PSTN operator in Moscow, MGTS is considered to be a company holding a dominant position as well as a natural monopoly in the Moscow telecommunications market under Russian antimonopoly regulations. Consequently, the Federal Tariff Service regulates MGTS' tariffs for most services provided to its PSTN subscribers, including installation fees, monthly subscription fees (for subscribers to the unlimited tariff plan) and local call charges (for subscribers who do not use the unlimited tariff plan). In addition, the interconnect tariffs established by Comstar and MGTS are also subject to regulation by the Federal Tariff Service. While we believe the tariffs currently set by the Federal Tariff Service are sufficient to compensate us for the costs of providing these services, future tariffs may not be set at a level that fully compensates us for the provision of these services or increased in parallel with corresponding increases in our costs and/or inflation.

        Although we are permitted to petition the Federal Tariff Service for increases in tariffs based on such criteria as inflation, increased costs and the need for network investments, it is possible that future requested increases may not be granted or that the Federal Tariff Service may not adequately take such factors into account in setting tariffs. If the tariffs applicable to Comstar and MGTS do not compensate us for the cost of providing services,materially adversely affect our business, andfinancial condition, results of operations could be materially adversely affected.and prospects.

If we or any of our mobile operator subsidiaries operating in Russia are identified as an operator occupying a "substantial position," the regulator may reduce our interconnect tariffs which, in turn, may have a material adverse effect on our financial condition and results of operations.

        In addition to the regulation of dominant operators by FAS, the Federal Law on Communications provides for the special regulation of telecommunications operators occupying a "substantial position,"i.e., operators which, together with their affiliates, have 25% or more of installed capacity or capacity to carry out transmission of not less than 25% of traffic in a geographically defined zone within in the Russian Federation. These regulations provide for governmental regulation of the key terms of such operators' interconnect agreements, including the interconnect tariffs. In addition, such operators are required to develop standard interconnect agreements and publish them as a public offer made to all operators who intend to interconnect to the networks of those operators. For additional information, see "Item 4. Information on Our Company—B. Business Overview—Regulation of Telecommunications in the Russian Federation and Ukraine—Regulation in the Russian Federation."

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        At present, the foregoing regulations apply only to fixed line operators in Russia including Comstar and MGTS. However, drafttherefore apply to our fixed line business. Draft legislation was introduced in 2008 that would extend the law to apply to mobile operators. Although the proposed law was not adopted, the risk that similar legislation will be introduced and adopted in the future remains. If legislation which extends the new legislationforegoing regulations to apply to mobile operators is adopted, and we and any of our mobile operator subsidiaries operating in Russia are identified as operators occupying a "substantial position," regulators may reduce our interconnectioninterconnect tariffs which, in turn, may have a material adverse effect on our revenues, financial condition and results of operations.

We and MGTS are subject to extensive regulation of our respective tariffs, and these tariffs may not fully compensate us for the cost of providing required services.

        As the PSTN operator in Moscow, MGTS is considered to be a company holding a dominant position as well as a natural monopoly in the Moscow telecommunications market under Russian antimonopoly regulations. Consequently, the Federal Tariff Service regulates MGTS' tariffs for most services provided to its PSTN subscribers, including installation fees, monthly subscription fees (for subscribers to the unlimited tariff plan) and local call charges (for subscribers who do not use the unlimited tariff plan). In addition, the Federal Law on Communications also provides for the special regulation of telecommunications operators occupying a "substantial position,"i.e., operators which together with their affiliates have, in the Russian Federation generally or in a geographically defined specific numerical zone, 25% or more of installed capacity or capacity to carry out transmission of not less than 25% of traffic. Comstar and MGTS were added to the register of telecommunications operators occupying a substantial position in 2005 and 2006, respectively. Accordingly, the interconnect tariffs established by Comstar, prior to its merger with us, and MGTS are also subject to regulation by the Federal Agency on Communications. Although we have not been formally recognized as a telecommunications operator occupying a substantial position on the market, we believe that interconnect tariffs previously approved by the Federal Agency on Communications for Comstar also apply to us following the merger completed on April 1, 2011. While we believe the tariffs currently set by the Federal Tariff Service and the Federal Agency on Communications are sufficient to compensate us for the costs of providing these services, future tariffs may not be set at a level that fully compensates us for the provision of these services or increased in parallel with corresponding increases in our costs and/or inflation.

        Although we are permitted to petition the Federal Tariff Service for increases in tariffs based on such criteria as inflation, increased costs and the need for network investments, it is possible that future requested increases may not be granted or that the Federal Tariff Service may not adequately take such factors into account in setting tariffs. If the tariffs applicable to Comstar (prior to its merger with us, but now, applicable to us), and MGTS do not compensate us for the cost of providing services, our business and results of operations could be materially adversely affected.

Changes to the rules and regulations involving roaming charges in Russia may adversely affect our financial condition and results of operations.

        In 2010, the Russian government announced its intent to monitor the pricing of roaming services. As a result, FAS conducted an investigation of the activities of Russian telecommunications operators and found that we, Vimpelcom and MegaFon violated antimonopoly laws relating to our pricing for roaming services. Subsequently, FAS imposed an administrative fine on us in the amount of RUR 21.9 million which represents 1.0% of the revenues we derived from roaming services in CIS countries in 2009. Since this decision, several draft laws were submitted for consideration to the State Duma, which are intended to change the regulation of so-called "national" (between networks) and "intra-network" (within network) roaming in Russia by introducing a flat national roaming tariff and eliminating intra-network roaming tariffs for incoming calls. It is not currently clear whether this legislation will be adopted. However, if the new legislation is adopted, we believe that our revenues

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from the provision of roaming services would decline considerably, which could have a material adverse effect on our financial condition and results of operations.

        In addition, in 2011, the Russian government continued its efforts to decrease the level of prices for international roaming services and entered into discussions with the European Commission regarding the roaming pricing strategy of both Russian and European telecommunications operators due to an increasing number of complaints from subscribers. Further to our conversations with FAS and in response to public discussions initiated by various Russian consumers associations, we, Megafon and Vimpelcom have voluntarily lowered international roaming tariffs and introduced certain tariff plans and options aimed at the reduction of prices for roaming services. See also "Item 4. Information on Our Company—Business overview—Sales and Marketing—Advertising and Marketing."

        However, if the Russian government determines the decrease of roaming tariffs to be insufficient, it may require us to decrease our prices for roaming services, which may adversely affect our revenues and financial condition. See also "—A finding by FAS that we have acted in contravention of antimonopoly legislation could have a material adverse effect on our business, financial condition and results of operation."

Compliance with the new regulations on International Mobile Equipment Identity ("IMEI") numbers may present us with technical difficulties and may lead to the expenditure of significant resources.

        On January 11, 2012, the Ministry of Communications and Mass Media published a draft regulation, which will require all handsets and other telecommunications devices to be assigned individual IMEI numbers. It is still unclear if and when this regulation will be adopted. If this regulation is adopted, we may be required to develop a system to monitor IMEI numbers, and we may need to establish and maintain a database of IMEI numbers, which would necessitate the expenditure of significant technical and financial resources.

The accession of Russia into the World Trade Organization ("WTO") may lead to legislative and other changes which may adversely affect our business, financial condition and results of operation.

        On December 16, 2011, Russia signed the accession protocol in order to enter into the WTO which may lead to significant changes in Russian legislation including, among others, regulation of foreign investments in Russian companies, competition laws, as well as changes in the taxation system and customs regulations in Russia. In addition, implementation of the WTO rules may lead to the increase of competition on the markets we operate. It is unclear yet if and when these legislative developments may take place. However, if the new legislation is implemented in Russia as a result of accession to the WTO and there is an increase in competition, this could have a material adverse effect on our financial condition and results of operations.

The enactment of regulations allowing mobile network subscribers to select their long distance providers could have a material adverse effect on our financial condition and results of operations.

        We currently provide long distance services to our subscribers pursuant to our license for mobile services and route the long distance traffic through long distance transit operators. We receive revenue from our subscribers for these calls, and remit an interconnectioninterconnect fee to the long distance transit operators. In providing long distance services, we select the transit operators based on cost and quality

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considerations. Subscribers making domestic or international long distance or ("DLD/ILD,ILD") calls on their mobile phones do not have the option of selecting their long distance provider.

        In contrast, fixed line telephone users in Russia have the legal right to select their long distance operator, either by pre-selecting the operator for all of their future calls, or through a "hot choice" option, the latter of which allows callers to select their preferred long distance provider before each long distance call.

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        The Ministry of Communications and Mass Media is currently considering whether to extend the right to select long distance providers to mobile network subscribers. In the event that this occurs, we will need to make substantial investments in our network infrastructure to support the "hot choice" feature. In addition, allowing our subscribers to select their long distance providers may result in their selection of higher cost providers, causing higher interconnect fees to be payable by us and, consequently, lower revenues. As a result, extending the right to select long distance providers to mobile subscribers could have a material adverse effect on our financial condition and results of operations.

Much of our fixed line infrastructure is outdated, and we may be required to make significant investments beyond those that are currently planned to modernize it.

        A significant portion of MGTS' infrastructure has not been modernized. For example, only approximately 63.4% of its active lines were digitalized as of December 31, 2009. As a result, those subscribers who connect to our fixed line network using analog lines will not be able to receive value-added services, such as voicemail and call forwarding. In addition, we will not be able to reduce substantially our number of employees and associated costs untilalthough MGTS has recently completed the digitalization of ourits network, is complete. Furthermore,the newly installed equipment may not function properly within parts of the network that have not yet been upgraded. In addition, MGTS' network switching equipment may become obsolete or unusable, in which case we may be required to make significant investments to modernize MGTS' infrastructure in order to ensure that it fulfills its regulatory obligation to provide telephony services as a PSTN operator. The overburdening of MGTS' infrastructure may inconvenience subscribers by causing incoming and outgoing calls to have lower completion rates.

        MGTS invested approximately 116 million1.5 billion rubles in 20092010 ($3.849.5 million as of December 31, 2009)2010) and approximately 1,328 million rubles in 2011 ($41.25 million as of December 31, 2011) and plans to invest approximately 2.215.1 billion rubles in 20102012 ($72.7468.3 million as of December 31, 2009)2011) to upgrade its infrastructure. If MGTS is not able to upgrade its network in a timely manner or if it is required to make significant investments beyond those that are currently planned, our business, financial condition, results of operations and prospects could be materially adversely affected.

We are subject to anti-corruption laws in the jurisdictions in which we operate, including anti-corruption laws of Russia and the US Foreign Corrupt Practices Act (the "FCPA"), and we may be subject to the UK Bribery Act of 2010 (the "UK Bribery Act"). Our failure to comply therewith could result in penalties which could harm our reputation and have a material adverse effect on our business, financial condition and results of operations.

        We are subject to the FCPA, which generally prohibits companies and their intermediaries from making improper payments to foreign officials for the purpose of obtaining or keeping business and/or other benefits, along with various other anti-corruption laws. We may also be subject to the recently-enacted UK Bribery Act. The UK Bribery Act is broader in scope than the FCPA in that it directly addresses commercial bribery in addition to bribery of government officials and it does not recognize certain exceptions, notably facilitation payments that are permitted by the FCPA. Although we regularly review and update our policies and procedures designed to ensure that we, our employees, distributors and other intermediaries comply with the anti-corruption laws to which we are subject, there is no assurance that such policies or procedures will work effectively all of the time or protect us against liability under these or other laws for actions taken by our employees, distributors and other intermediaries with respect to our business or any businesses that we may acquire. We operate primarily in Russia and other countries of the former Soviet Union, many of which pose elevated risks of anti-corruption violations. We and certain of our subsidiaries are in frequent contact with persons who may be considered "foreign officials" under the FCPA and UK Bribery Act, and therefore, are subject to an increased risk of potential FCPA and UK Bribery Act violations. If we are not in compliance with the FCPA, the UK Bribery Act and other laws governing the conduct of business with government entities (including local laws), we may be subject to criminal and civil penalties and other remedial measures, which could have an adverse impact on our business, results of operations, financial condition and liquidity. Any investigation of any potential violations of the FCPA, the UK Bribery Act

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or other anti-corruption laws by US, UK or foreign authorities could also have an adverse impact on our business, financial condition and results of operations.

Our intellectual property rights are costly and difficult to protect.

        We regard our copyrights, trademarks, trade secrets and similar intellectual property, including our rights to certain domain names, as important to our continued success. We rely upon trademark and copyright law, trade secret protection and confidentiality or license agreements with our employees, customers, partners and others to protect our proprietary rights. Nonetheless, intellectual property rights are especially difficult to protect in the markets where we operate. In these markets, the regulatory agencies charged to protect intellectual property rights are inadequately funded, legislation is underdeveloped, piracy is commonplace and enforcement of court decisions is difficult. For example, in Russia, legislation in the area of copyrights, trade markstrademarks and other types of intellectual property was significantly changed in 2008, and Russian courts have limited experience in applying and interpreting the new laws.

        In addition, litigation may be necessary to enforce our intellectual property rights, to determine the validity and scope of the proprietary rights of others, or to defend against claims of infringement. Any such litigation may result in substantial costs and diversion of resources, and, if decided unfavorably to us, could have a material adverse effect on our business and results of operations. We also may incur

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substantial acquisition or settlement costs where doing so would strengthen or expand our intellectual property rights or limit our exposure to intellectual property claims of third parties.

We are in the process of transferring to a new billing system and optimizing our information technology infrastructure, which could have a material adverse effect on our business and results of operations in the short term.

        We have substantially completed implementation of a new billing system in Russia and Belarus. The transitionWe have also completed the transfer of our individual subscribers in Ukraine to a new billing system, and are approaching the final stage of transferring our individual subscribers in Uzbekistan to a new billing system. In addition, we may face difficulties and delays in implementing the new billing system in the other countries where we operate will take longer to complete.newly acquired companies. Although we have already begun to experience increases in our overall efficiency and reductions in our expenses as a result of the new billing system, we arein Ukraine it is still requirednecessary for us to run both the old and new billing systems simultaneously during the transition period, creating additional burdens on our technical support staff. We may also experience technical problems with the new billing system during the transition period. These factors may increase our operational risks and expenses and inconvenience for subscribers in the short term. In addition, we are also currently optimizing our information technology infrastructure, which may result in temporary technical disruptions. The failure or breakdown of key components of our infrastructure in the future, including our billing system and its susceptibility to fraud, could have a material adverse effect on our business and results of operations.

If leaks of confidential information, including information relating to our subscribers, occur it may negatively impact our reputation and our brand image and lead to a loss of market share, which could materially adversely affect our business, financial condition, results of operations and prospects.

        Although we make efforts to protect confidential information, breaches of security and leaks of confidential information, including information relating to our subscribers, may negatively impact our reputation and our brand image and lead to a loss of market share, which could materially adversely affect our business, financial condition, results of operations and prospects.

For example, in January 2003, we discovered that part of our database of subscribers, containing private subscriber information, was illegally copied and stolen. The database contained information such as the names, addresses, home phone numbers, passport details and other personal information of approximately five million of

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our subscribers. In addition, in May 2003, certain subscriber databases of several operators in the North-West region, including those of us, MegaFon, Delta Telecom and two other operators, were stolen. In each case, the stolen databases were thereafter available for sale in Russia.

In December 2003, we completed our internal investigation relating to the theft of our subscriber databases and found that these incidents were due to weaknesses in our internal security in relation to physical access to such information. We have taken measures that we believe will prevent such incidents from occurring in the future, but such incidents may nonetheless recur.

        In January 2003, lawsuits were filed by two of our subscribers seeking compensation for damages resulting from the leak of the subscribers' confidential information. While the subscribers subsequently withdrew their claims, if similar lawsuits are successful in the future, we might have to pay significant damages, including consequential damages, which could have a material adverse effect on our results of operations.

Alleged medical risks of cellular technology may subject us to negative publicity or litigation, decrease our access to base station sites, diminish subscriber usage and hinder access to additional financing.

        Electromagnetic emissions from transmitter masts and mobile handsets may harm the health of individuals exposed for long periods of time to these emissions. The actual or perceived health risks of transmitter masts and mobile handsets could materially adversely affect us by reducing subscriber growth, reducing usage per subscriber, increasing the number of product liability lawsuits, increasing the difficulty in obtaining or maintaining sites for base stations and/or reducing the financing available to the wireless communications industry.

Table Each of Contentsthese potential circumstances may adversely affect our business, financial condition, results of operations and prospects.

Risks Relating to Our Financial Condition

We may be adversely affected by the current economic environment.

        As a result of the credit market crisis (including uncertainties with respect to financial institutions and the global capital markets), decreased prices for major export commodities (including oil and metals) and other macro-economic challenges currently affecting many of the economies in which we operate, our subscribers' disposable incomes and our vendors' cash flows may be adversely impacted. Consequently, subscribers may modify or decrease their usage of our services or fail to pay the outstanding balances on their accounts, and vendors may significantly increase their prices, eliminate vendor financing or reduce their output.

        We may also experience increases in accounts receivable and bad debt among corporate subscribers, some of whom may face liquidity problems and potential bankruptcy, as well as the potential bankruptcy of our corporate partners. For example, in 2008, we extended a short-term loan to Closed Joint Stock Company "Beta Link",Link," or Beta Link, mobile handset retailer and MTS dealer, for $28.2 million. Beta Link subsequently filed for bankruptcy in March 2009, and we believe it is unlikely that we will be able to recover the loan amount or accounts receivable due from Beta Link. See also "Item 8. Financial Information—A. Consolidated Statements and Other Financial Information—7. Litigation" and Note 5 to our audited consolidated financial statements.Litigation."

        A decline in subscriber usage, an increase in bad debts, material changes in equipment pricing or financing terms or the potential bankruptcy of our corporate subscribers or partners may have a material adverse effect on our business, financial condition, results of operations and prospects.

        In addition, a deterioration in macroeconomic conditions could require us to reassess the value of goodwill on certain of our assets, recorded as a difference between the fair value of the assets of business acquired and its purchase price. This goodwill is subject to impairment tests on an ongoing basis. The weakening macroeconomic conditions in the countries in which we operate and/or a significant difference between the performance of an acquired company and the business case assumed at the time of acquisition could require us to write down the value of the goodwill or portion of such value. Future write downs relating to the value of the goodwill or portion of such value could have a material adverse effect on our financial condition and results of operations.

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Continued turmoil in the credit markets could cause our business, financial condition, results of operations and the value of our shares and ADSs to suffer.

        Since the summer of 2007, turmoil in the international credit markets, the recession in the United States and several major European economies and the collapse or near collapse of several large banks and financial services companies in the United States and United Kingdom have resulted in increased volatility in the securities markets in the United States and across Europe, including Russia. In addition, many financial market indices in Russia and other emerging markets, as well as developed markets, have declined significantly since the summer of 2008, and continue to be depressed. Continued volatility in the United States, European and/or Russian securities markets stemming from these or other factors may continue to adversely affect the value of our shares and ADSs.

        The downturn in the global financial markets has also caused some companies to experience difficulties accessing their cash equivalents, trading investment securities, drawing on revolvers, issuing debt and raising capital generally. A continuation of this downturn and resulting volatility of the trading price of our shares and ADSs may negatively impact our ability to obtain financing on commercially reasonable terms and the level and volatility of the trading price of our shares and ADSs, and could have a material adverse effect on our business, financial condition, results of operations and prospects.

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Servicing and refinancing our indebtedness will require a significant amount of cash. Our ability to generate cash or obtain financing depends on many factors beyond our control.

        We have a substantial amount of outstanding indebtedness, primarily consisting of the obligations we entered into in connection with our notes and bank loans. As of December 31, 2009,2011, our consolidated total debt, including capital lease obligations, was $8,329.5$8,715 million. Our interest expense for the year ended December 31, 20092011 was $571.7$656,899 million, net of amounts capitalized.

        Our ability to service, repay and refinance our indebtedness and to fund planned capital expenditures will depend on our ability to generate cash in the future. This, to a certain extent, is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond our control. If we are unable to generate sufficient cash flow or otherwise obtain funds necessary to make required payments, we may default under the terms of our indebtedness, and the holders of our indebtedness would be able to accelerate the maturity of such indebtedness, potentially causing cross-defaults under and acceleration of our other indebtedness. Furthermore, as of December 31, 2009,2011, approximately 35%14.7% of the debt we have incurred is at floating rates of interest linked to indices, such as LIBOR and EURIBOR, and we have hedged the interest rate risk only with respect to approximately 65%21.6% of our floating interest rate debt. As a result, our interest payment costs can increase if such indices rise.

        We may not be able to generate sufficient cash flow or access international capital markets or incur additional indebtedness to enable us to service or repay our indebtedness or to fund our other liquidity needs. We may be required to refinance all or a portion of our indebtedness on or before maturity for a number of reasons; for example, the terms of some of our loan agreements may require us to prepay the loan in certain circumstances, such as a deterioration in our credit rating, we are delisted or our retained earnings drop below a certain level. This, in turn, may force us to sell assets, reduce or delay capital expenditures or seek additional capital. Refinancing or additional financing may not be available on commercially reasonable terms or at all, and we may not be able to sell our assets or, if sold, the proceeds therefrom may not be sufficient to meet our debt service obligations. Our inability to generate sufficient cash flow to satisfy our debt service obligations, or to refinance debt on commercially reasonable terms, would materially adversely affect our business, financial condition, results of operations and prospects. See "Item 5. Operating and Financial Review and Prospects— B. Liquidity and Capital Resources."

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Ruble depreciation and regulatory changes in foreign currency regulation could increase our costs, decrease our cash reserves, or make it more difficult for us to comply with financial ratios and to repay our debts and will affect the value of dividends received by holders of ADSs.

        Over the past two decades, the ruble has fluctuated, at times substantially over short periods of time, against the U.S. dollar. In particular, it significantly depreciated against the U.S. dollar in 2008 and 2009 as a result of the ongoing global financial downturn. For example, on December 31, 2008, the official exchange rate published by the Central Bank of Russia or CBR,("CBR") was 29.38 rubles per one U.S. dollar, as compared to 24.55 rubles per one U.S. dollar on December 31, 2007. The ruble continued to depreciate against the U.S. dollar in early 2009, reaching 36.43 rubles per one U.S. dollar on February 19, 2009. As of December 31, 2009,2011, the exchange rate was 30.2432.20 rubles per one U.S. dollar and as of May 1, 2010,April 20, 2012, the exchange rate was 29.1529.51 rubles per one U.S. dollar. The ruble has also depreciated against the euro. On December 31, 2009,2010 and 2011, the official exchange rate was 43.3840.33 rubles and 41.67 rubles per one euro, respectively, as compared to 41.4443.38 rubles and 35.9341.44 rubles per one euro on December 31, 20082009 and 2007,2008, respectively.

        Currently, the Russian foreign currency market is regulated by legislation, which is aimed at liberalization of currency regulation and lowering of administrative barriers. This legislation provides a general framework and a set of rules, within which both the Russian government and the CBR are authorized to propose various regulations, which result in uncertainty for us in carrying out importation of equipment. The CBR from time to time has imposed various currency-trading restrictions in attempts to support the ruble. The ability of the government and the CBR to maintain a stable ruble will depend on many political and economic factors. These include their ability to finance the budget without

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recourse to monetary emissions, to control inflation and to maintain sufficient foreign currency reserves to support the ruble. Furthermore, changes in foreign currency regulation may affect our ability to fund payments denominated in foreign currency and result in us entering into supplementary agreements with our foreign counterparts.

        A majority of our capital expenditure and liabilities and borrowings are either denominated in or tightly linked to the U.S. dollar. Conversely, a majority of our revenues are denominated in rubles. As a result, devaluation of the ruble against the U.S. dollar can adversely affect us by increasing our costs in rubles, both in absolute terms and relative to our revenues, and make it more difficult to comply with the financial ratios contained in our various loan agreements or fund cash payments on our indebtedness on time. A decline in the value of the ruble against the U.S. dollar will also result in a translation loss when we translate the ruble revenues into U.S. dollars for inclusion in our audited consolidated financial statements. It also reduces the U.S. dollar value of tax savings arising from tax incentives for capital investment and the depreciation of our property, plant and equipment, since their basis for tax purposes is denominated in rubles at the time of the investment. Increased tax liability would also increase total expenses.expenses, which would have an adverse impact on our results.

        We also anticipate that any dividends we may pay in the future on the shares represented by the ADSs will be declared and paid to the depositary in rubles and will be converted into U.S. dollars by the depositary and distributed to holders of the ADSs. Accordingly, the value of dividends received by holders of ADSs will be subject to fluctuations in the exchange rate between the ruble and the U.S. dollar. Depreciation of the ruble against the U.S. dollar could therefore materially adversely affect our financial condition, results of operations and prospects and the value of the ADSs. See also "Item 11. Quantitative and Qualitative Disclosures about Market Risk—Foreign Currency Risk."

Changes in the exchange rate of local currencies in the countries where we operate against the U.S. dollar and/or euro could adversely impact our revenues reported in U.S. dollars and costs in terms of local currencies.

        A significant portion of our expenditures and liabilities, including capital expenditures and borrowings (including our U.S. dollar denominated notes), are either denominated in, or closely linked

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to, the U.S. dollar and/or euro, while substantially all of our revenues are denominated in local currencies of the countries where we operate. As a result, the devaluation of local currencies against the U.S. dollar and/or euro can adversely affect our revenues reported in U.S. dollars and increase our costs in terms of local currencies. If local currencies decline against the U.S. dollar and/or euro and price increases cannot keep pace, we could have difficulty repaying or refinancing our U.S. dollar and/or euro-denominated indebtedness, including our U.S. dollar denominated notes. In addition, local regulatory restrictions on the sale of hard currency in Turkmenistan and Uzbekistan may delay our ability to purchase equipment and services necessary for network expansion which, in turn, may cause difficulty in expanding our subscriber base in those countries.that country. Further, a portion of our cash balances is held in jurisdictions outside Russia, and as a result of exchange controls in those jurisdictions, these cash balances may not always be readily available for our use.

        The Ukrainian hryvnia experienced significant volatility over the last quarter of 2008 and in 2009, with the official exchange rate falling from 4.86 hryvnias per one U.S. dollar as of October 1, 2008 to 7.70 hryvnias and 7.97 hryvnias per one U.S. dollar as of December 31, 2008, and 2009, respectively. The official exchange rate stabilized in the last two years and was 7.96 hryvnias and 7.99 hryvnias per U.S. dollar as of December 31, 2010 and 2011, respectively.

        The Belarusian ruble experienced significant volatility in 2011, with the official exchange rate volatilityfalling from 3,000.00 rubles per one U.S. dollar as of January 1, 2011 to 4,970.00 rubles per one U.S. dollar as of June 1, 2011 and to 8,450 rubles per one U.S. dollar as of November 1, 2011. On May 23, 2011, the National Bank of the Republic of Belarus announced the significant devaluation of the Belarusian ruble against major foreign currencies to stabilize the situation on the foreign currency exchange market. Furthermore, the three-year cumulative inflation rate for Belarus exceeded 100 percent as of September 30, 2011, thereby meeting the quantitative requirement under U.S. GAAP for its economy to be considered highly inflationary, and we have accordingly accounted for this in our financial statements. The continued devaluation of the Turkmenistan manatBelarusian ruble and the highly inflationary economy may also adversely affect our revenues from this market. From 1998See also "—Risks Relating to 2007, the official Turkmenistan manat to U.S. dollar exchange rate was fixed at 5,200 manat per one U.S. dollar. In January 2008, a Presidential Decree was issued establishing a new official exchange rate at 6,250 manat per one U.S. dollarOur Financial Condition—Inflation could increase our costs and a commercial exchange rate at which companies and banks can buy and sell currencyadversely affect our results of up to 20,000 manat per one U.S. dollar. In May 2008, an additional Presidential Decree changed the official exchange rate to 14,250 manat per one U.S. dollar. As a result of the changes in the manat-to-U.S. dollar exchange rate, the revenues of MTS-Turkmenistan declined significantly in the year ended

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December 31, 2008, as we experienced a significant currency exchange loss when translating the manat revenue of MTS-Turkmenistan to U.S. dollars, our reporting currency.

        On December 31, 2008, the Central Bank of Turkmenistan announced the redenomination of the manat and the introduction of new banknotes and coins of national currency as of January 1, 2009. Under the new currency, 1 new manat equals 5,000 old manat. The Central Bank of Turkmenistan established the exchange rate at 2.85 new manat per one U.S. dollar. As conversion of local currency in Turkmenistan is subject to government regulations, it is difficult to predict the extent of further exchange rate fluctuations. See alsooperations," "Item 11. Quantitative and Qualitative Disclosures about Market Risk—Foreign Currency Risk."Risk" and Note 2 to our audited consolidated financial statements.

A disposition by our controlling shareholder of its stake in our company could materially harm our business.

        Under certain of our debt agreements, an event of default may be deemed to have occurred and/or we may be required to make a prepayment if Sistema disposes of its stake in our company orand a third party takes a controlling position in our company. The occurrence of any such event of default or failure to make any required prepayment which leads to an event of default could trigger cross default/cross acceleration provisions under certain of our other debt agreements. In such event, our obligations under one or more of these agreements could become immediately due and payable, which would have a material adverse effect on our business and our shareholders' equity. If Sistema were to dispose of its stake in us, our company may be deprived of the benefits and resources that it derives from Sistema, which could harm our business.

If we are unable to obtain adequate capital, we may have to limit our operations substantially, which could have a material adverse effect on our business, financial condition, results of operations and prospects.

        We will need to make significant capital expenditures, particularly in connection with the development, construction and maintenance of, and the purchasing of software for our mobile and fixed line networks. We spent $1,899.0 million in 2007, $2,612.8 million in 2008 and $2,328.3 million in 2009, $2,647.1 million in 2010 and $2,585 million in 2011, for the fulfillment of our capital spending plans. In addition, the acquisition of 3G licenses and frequency allocations and the buildoutbuild-out of our 3G and broadband Internet networks will require additional capital expenditures. However, future financings and cash flow from our operations may not

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be sufficient to meet our planned needs in the event of various unanticipated potential developments, including the following:

•

a lack of external financing sources;



•

changes in the terms of existing financing arrangements;



•

construction of the wireless networks at a faster rate or higher capital cost than anticipated;



•

pursuit of new business opportunities or investing in existing businesses that require significant investment;



•

acquisitions or development of any additional wireless licenses;



•

slower than anticipated subscriber growth;



•

slower than anticipated revenue growth;



•

regulatory developments;



•

changes in existing interconnect arrangements; or



•

a deterioration in the economies of the countries where we operate.

        Our indebtedness and the limits imposed by covenants in our debt obligations could limit our ability to obtain additional financing and thereby constrain our ability to invest in our business and

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place us at a possible competitive disadvantage relative to our competitors. Also, currently we are not able to raise equity financing through newly issued depositary receipts such as ADSs, due to Russian securities regulations providing that no more than 25% of a Russian company's shares may be circulated abroad through sponsored depositary receipt programs. Prior to December 31, 2005 and at the time of our initial public offering, this threshold was 40% and our current ADSs program is near its full capacity. If we cannot obtain adequate funds to satisfy our capital requirements, we may need to limit our operations significantly, which could have a material adverse effect on our business, financial condition, results of operations and prospects.

Inflation could increase our costs and adversely affect our results of operations.

        The Russian and Ukrainian economies have been characterized by high rates of inflation. According to the Federal Statistics Service, inflation reached 8.8% and 6.1% in Russia in 2009.2010 and 2011, respectively. Inflation reached 15.9%9.4% and 8.0% in Ukraine in 2009,2010 and 2011, respectively, according to the State Statistics Committee of Ukraine. As we tend to experience inflation-driven increases in certain of our costs, which are sensitive to rises in the general price level in Russia and Ukraine, our costs will rise. In addition, media inflation in Russia continues to be very high and shows little sign of slowing, which may lead to higher marketing expenditures by us in order to remain competitive. In this situation, due to competitive pressures, we may not be able to raise the prices we charge for our products and services sufficiently to preserve operating margins. Accordingly, high rates of inflation in Russia and Ukraine could increase our costs and decrease our operating margins. See also "Item 5. Operating and Financial Review and Prospects—A. Operating Results—Certain Factors Affecting our Financial Position and Results of Operations—Inflation."

        In May 2011, Belarus announced a significant devaluation of the Belarusian ruble against major foreign currencies. Furthermore, the three-year cumulative inflation rate for Belarus exceeded 100 percent as of September 30, 2011, thereby meeting the quantitative requirement under U.S. GAAP for its economy to be considered highly inflationary, and we have accordingly accounted for this in our financial statements. See Note 2 to our audited consolidated financial statements. Since most of our revenues in Belarus are denominated in local currency, the devaluation has resulted in lower revenues in dollar terms. Additionally, since a significant portion of our operating costs are denominated or tied to foreign currency, the devaluation and high inflation have also resulted in higher operating costs in

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comparison to revenues. Accordingly, the devaluation and the highly inflationary economy in Belarus may materially adversely affect our revenues and results of operations in that country. See also "—Risks Relating to Our Financial Condition—Changes in the exchange rate of local currencies in the countries where we operate against the U.S. dollar and/or euro could adversely impact our revenues reported in U.S. dollars and costs in terms of local currencies" and "Item 11. Quantitative and Qualitative Disclosures about Market Risk—Foreign Currency Risk."

Our failure to fulfill our iPhone handset purchase commitment under our agreement with Apple Sales International could have a material adverse effect on our financial condition and results of operations.

        In September 2008, we entered into an unconditional purchase agreement with Apple Sales International to buy certain quantities of iPhone handsets at list prices at the dates of the respective purchases over a three-year period.purchases. Pursuant to the agreement, we are also to incur certain iPhone promotional costs. In both 2009 and 2008, weWe did not fulfill our total purchase installment contemplated by the agreement.agreement in 2011, 2010, 2009 and 2008. As a result, it is possible that Apple may bring a claim against us, which could have a material adverse effect on our financial condition and results of operations. To date, Apple has not brought a claim against us. The total amount paid for handsets purchased under the agreement for the years ended December 31, 2011, 2010, 2009 and 2008 amounted to $140.8 million, $79.4 million, $3.4 million and $65.4 million, respectively. The purchase agreement with Apple Sales International expired on March 31, 2012, and we intend to negotiate an extension of this agreement. Failure to renew the agreement with Apple Sales International on commercially acceptable terms or at all may adversely affect our financial condition and results of operations.

Indentures relating to our notes contain, and some of our loan agreements and Sistema's loan agreements contain, restrictive covenants, which limit our ability to incur debt and to engage in various activities.

        Covenants in the loan agreement relating to our notes due 2020 limit our ability to create liens on our properties, merge or consolidate with another person or convey our properties and assets to another person. Additionally, our outstanding notes containthe loan agreement contains covenants limiting our ability to incur debt, create liens on our properties, enter into sale and lease-back transactions, merge or consolidate with another person or convey our properties and assets to another person, as well as our ability to sell or transfer any of our or our subsidiaries' GSM licenses for the Moscow, St. Petersburg, Krasnodar and Ukraine license areas. Some of our loan agreements contain similar and other covenants, including in relation to the incurrence of indebtedness, creation of liens and disposal of assets. Failure to comply with these covenants could cause a default and result in the debt becoming immediately due and payable, which would materially adversely affect our business, financial condition and results of operations.

        In addition, Sistema, which controls 52.7%owns 50.8% of our total charter capital (54.8%(52.8% excluding treasury shares) and consolidates our results in its financial statements, is subject to various covenants in its credit facilities. These covenants impose restrictions on Sistema and its restricted subsidiaries (including

as the "settlement rate." Any reduction of the settlement rate by the regulator could have a negative impact on our average monthly service revenues per subscriber and margins.

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        In addition, FAS recently indicated its intention to introduce a draft law which would require telecommunications operators, including us, to base their tariffs on per-second billing. It is not clear yet whether this draft law will be adopted; however, if the proposed changes, including the switch from per-minute billing to per-second billing, become effective, the new law may have a negative impact on our revenues and results of operations.

        Additionally, President Dmitry Medvedev has recently called for the implementation of new rules to allow customers in Russia to retain their mobile phone numbers after switching their mobile operator and has asked the Ministry of Communications and Mass Media and the Prosecutor General's Office to review this issue. If new rules that mandate mobile number portability are introduced, they may have a material adverse effect on our financial condition and results of operation.

        Furthermore, potential regulatory changes that may be enacted in the future, such as mobile numbering portability and the introduction of new rules regulating MVNOs, could weaken our competitive position in the mobile telecommunications market and, as a result, materially adversely affect our financial condition and results of operations.

Our failure to comply with new personal data protection laws in Russia may have a material adverse effect on our business, financial condition and results of operations.

        The Federal Law on Personal Data and certain regulations enacted thereunder require us to bring our information storage, processing and protection practices to be in compliance with the statutory standards, by Januaryeffective as of July 1, 2011. The implementationAdditionally, various amendments to the current regulatory regime have been proposed by the State Duma, the Ministry of Communications and Mass Media, the Federal Service for Technical and Export Control, and the Federal Security Service, in order to increase regulatory oversight over data protection.

        As a result of these standards involvesand other changes in personal data protection regulations, we are faced with significant technical, financial and managerial undertakings. For example, we will beare required to treat subscribers' personal data with the level of protectionsprotection afforded to state secrets, obtain state certification of our installed information protection facilities from the Federal Service for Technical and Export Control and the Federal Security Service and ensure that our automated accounting systems do not have any undeclared capabilities. We are also now directly liable for the actions of third parties to whom we forward personal data for processing. Moreover, we must now make public our data protection policies, which currently comprise a trade secret, and which may increase the risk of data protection violations if revealed. Furthermore, the modernization of our information protection systems and the optimization and reengineering of our personal data processing systems will require us to incur significant expenses. At the same time, the standardsnew regulations contain significant ambiguity and in certain cases their implementation may be impossible on technical grounds, which may impede our ability to comply and creates the potential for Russian authorities to form differing views on compliance. It is expected that by the middle of 2012 current standards will be supplemented by government regulations which will detail these standards. However, although the regulations are only expected in 2012, the Federal Law on Personal Data applies to relevant data protection systems as of July 1, 2011.

        If the resources required to develop and implement data protection systems meeting the new standards are greater than expected, or we fail to comply with the data protection laws despite our best efforts to do so, our business, financial condition and results of operations could be materially adversely affected.

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Changes in Ukrainian telecommunications legislation have caused uncertainty in relation to the regulation of the Ukrainian telecommunications industry and may adversely affect our business, financial condition and results of operations.

        The Ukrainian Law on Telecommunications came into force on December 23, 2003 (certain articles became effective in 2004 and 2005). However, certain regulatory bodies established by the law were unable to duly exercise their regulatory functions for an extended period of time. For example, the NCRC was established in August 2004 by a Decree of the President of Ukraine. On January 1, 2005, it was vested with the powers of the central regulatory body in the sphere of communications by the Ukrainian Law on Telecommunications. The NCRC was considered formed and began to perform its regulatory activity in April 2005, when both the chairperson and its members were appointed as required by the Ukrainian Law on Telecommunications. However, in 2007 and 2008, the authority to appoint the NCRC chairperson and its members became the subject of a dispute between the President of Ukraine and the Cabinet of Ministers of Ukraine and the respective appointments were challenged in Ukrainian courts because of conflicting orders and regulations issued by the President of Ukraine and the Cabinet of Ministers. On October 8, 2008, the Constitutional Court of Ukraine passed a resolution pursuant to which the right of the Cabinet of Ministers to appoint the NCRC members and adopt its regulations was confirmed. Thus,On September 30, 2010, the Constitutional Court of Ukraine passed another decision which stated that members and the chairperson of the NCRC chairperson and its members are currentlyto be appointed by the CabinetPresident of Ministers. However, this uncertaintyUkraine.

        On November 23, 2011, the NCRC was dissolved and any future challengesthe Ukrainian government created the NCCIR. As a result of the NCRC dissolution, the State Inspection of Communications has similarly been dissolved and there are currently no provisions in the legislation that would provide for a similar regulatory body or for its authority. The authority granted to the NCRC'sNCCIR is largely similar to the authority or composition may have an adverse effect on our business, financial condition and results of operations.that was afforded to the NCRC.

        In addition, the Ukrainian Law on Telecommunications may require, among other things, companies with adeclared to have dominant position inon the telecommunications market to develop public telecommunications services if directed to do so by the regulatory authorities. As, according to AC&M-Consulting, the market share of MTS-Ukraine in mobile telecommunications services inOn June 24, 2010, MTS Ukraine was 31.8% as of December 31, 2009,found to have a dominant position on the interconnect market by the AMC. Accordingly, the implementation of this law may materially adversely

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affect our business, financial condition and results of operations. See "Item 4. Information on Our Company—B. Business Overview—Regulation of Telecommunications in the Russian Federation and Ukraine—Regulation in Ukraine—Legislation."

The Russian taxation system is underdeveloped and any imposition of significant additional tax liabilities could have a material adverse effect on our business, financial condition or results of operations.

        The discussion below provides general information regarding Russian taxes and is not intended to be inclusive of all issues. Investors should seek advice from their own tax advisors as to these tax matters before investing in our shares and ADSs. See also "Item 10. Additional Information—E. Taxation."

        In general, taxes payable by Russian companies are substantial and numerous. These taxes include, among others, corporate income tax, value added tax, property taxes, excise duties, payroll-related taxes and other taxes.

        Russian tax laws, regulations and court practice are subject to frequent change, varying interpretation and inconsistent and selective enforcement. In some instances, although it may be viewed as contrary to Russian constitutional law, the Russian tax authorities have applied certain new tax laws retroactively, issued tax claims for periods for which the statute of limitations had expired and reviewed the same tax period multiple times.

        On October 12, 2006, the Plenum of the High ArbitrationArbitrazh Court of the Russian Federation issued Resolution No. 53 formulating the concept of "unjustified tax benefit," which is described in the

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Resolution by reference to circumstances, such as absence of business purpose or transactions where the form does not match the substance, and which could lead to the disallowance of tax benefits resulting from the transaction or the recharacterization of the transaction. There has been very little further guidance on the interpretation of this concept by the tax authorities or courts, but it is likely that the tax authorities will actively seek to apply this concept when challenging tax positions taken by taxpayers in Russian courts. While the intention of this Resolution might have been to combat abuse of tax laws, in practice, there is no assurance that the tax authorities will not seek to apply this concept in a broader sense.

        Generally, tax returns in Russia remain open and subject to tax audit by the tax authorities for a period of three calendar years immediately preceding the year in which the decision to conduct a tax audit is taken. The fact that a year has been reviewed by the tax authorities does not prevent further review of that year, or any tax return applicable to that year, during the eligible three-year period by a superior tax authority.authority or, in certain limited instances, by a tax authority which conducted an initial review.

        On July 14, 2005, the Constitutional Court of the Russian Federation issued a decision that allows the statute of limitations for tax penalties to be extended beyond the three-year term set forth in the tax laws if a court determines that the taxpayer has obstructed or hindered a tax audit. Moreover, recentAdditionally, according to amendments to the Tax Code of the Russian Federation, effective January 1, 2007, provide for the extension of the three-year statute of limitations may be extended if the actions of the taxpayer created insurmountable obstacles for the tax audit. Because none of the relevant terms is defined, tax authorities may have broad discretion to argue that a taxpayer has "obstructed" or "hindered" or "created insurmountable obstacles" in respect of a tax audit and to ultimately seek review and possibly apply penalties beyond the three-year terms. According to Presidium of High Arbitrazh Court Resolution #4134/11 of September 27, 2011, the statute of limitations for tax penalties is calculated starting from the day immediately following the expiration of the tax period when the violation was committed.

        On March 17, 2009, the Constitutional Court of the Russian Federation issued a decision preventing the Russian tax authorities from carrying out a subsequent tax audit of a tax period if, following the initial audit of such tax period, a court decision was made concerning a tax dispute between the relevant taxpayer and the relevant tax authority arising out of such tax period, and such decision has not been revised or discharged. Currently it is not clear how this decision will be applied byThe Constitutional Court of the Russian Federation then issued Decision # 138-O-P on January 28, 2010, which confirmed the above approach. Subsequently, the Presidium of High Arbitrazh Court held in several cases that under certain circumstances (in particular, when the case has not been considered in substance) a superior tax authorities.body is still entitled to conduct a tax audit with respect to re-opened tax periods and taxes already reviewed during the initial tax audit; however, the circumstances under which the audit is conducted should differ from the initial ones (# 14585/09 of March 16, 2010, # 17099/09 of May 25, 2010, # 7278/10 of October 20, 2010).

        There is no guarantee that the tax authorities will not review our compliance with applicable tax law beyond the three-year limitation period. Any such review could, if it concluded that we had

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significant unpaid taxes relating to such periods, have a material adverse effect on our business, financial condition, results of operations and prospects.

        Moreover,As of January 1, 2012, changes to the financial resultsTax Code of Russian companies cannot be consolidated for tax purposes. Therefore, each of our Russian subsidiaries pays its own Russian taxes and may not offset its profit or loss against the loss or profit of any of our other subsidiaries. In a policy document entitled "Major Trends in Russian Tax Policy for 2009-2011," the Russian Government proposed to introduce consolidated tax reporting in order toFederation enable Russian taxpayers which are already part of a group for profit tax purposes to consolidate their financial results. We are awareresults for profit tax purposes. It is yet unclear how the new legislative provisions will be applied by the tax authorities as currently only limited regulatory guidance is available on this matter. In addition to imposing certain criteria that must be met in order to create a draft law on consolidated tax reporting has already been drafted; however, at this stage it is not possible to predict whether, when or in what formgroup of taxpayers, the law willalso limits certain transactions within the group (e.g. corporate restructurings, etc.). Given the uncertainty regarding this law, we may not be enacted.able to benefit from this new legislation.

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        In addition, intercompany dividends are subject to a withholding tax of 0% or 9% (depending on whether the recipient of dividends qualifies for Russian participation exemption rules), if being distributed to Russian companies, and 15% (or lower, subject to benefits provided by relevant double tax treaties), if being distributed to foreign companies. If the receiving company itself pays a dividend, it may offset tax withheld against its own withholding liability of the onward dividend although not against any withholding made on a distribution to a foreign company. These tax requirements impose additional burdens and costs on our operations, including management resources.

        The Russian tax authorities may take a more assertive position in their interpretation of the legislation and assessments, and it is possible that transactions and activities that have not been challenged in the past may nonetheless be subject to challengechallenges in the future. The foregoing factors raise the risk of the imposition of arbitrary or onerous taxes on us, which could adversely affect the value of our shares and ADSs.

        Current Russian tax legislation is, in general, based upon the formal manner in which transactions are documented, looking to form rather than substance. However, the Russian tax authorities in some cases, are increasingly taking a "substance and form" approach, which may cause additional tax exposures to arise in the future. Additional tax exposures could have a material adverse effect on our business, financial condition, results of operations and prospects.

        It is expected that Russian tax legislation will become more sophisticated, which may result in the introduction of additional revenue raising measures. Although it is unclear how any new measures would operate, any such introduction may affect our overall tax efficiency and may result in significant additional taxes becoming payable. Additional tax exposures could have a material adverse effect on our business, financial condition, results of operations and prospects.

        In addition to the usual tax burden imposed on Russian taxpayers, these conditions complicate tax planning and related business decisions. For example, tax laws are unclear with respect to deductibility of certain expenses. This uncertainty could possibly expose us to significant fines and penalties and to enforcement measures, despite our best efforts at compliance, and could result in a greater than expected tax burden.

        In January 2008, the Russian tax authorities initiated an audit of our compliance with tax legislation for the years ended December 31, 2005 and 2006. Based on the results of this audit, we were assessed anwith additional tax liability in the amount of 1,130.0 million rubles (approximately $38.5 million as of December 31, 2008), including taxes, fines and penalties. As of December 31, 2008, we paid to the tax authorities the full amount assessed. However, we also filed a petition with the ArbitrationArbitrazh Court of the Moscow District seeking to invalidate part of the assessment in the amount of 1,026.1 million rubles (approximately $34.9 million as of December 31, 2008). In December 2008, the court ruled to partially invalidate the assessment in the amount of 981.5 million rubles (approximately $33.4 million as of December 31, 2008). This rulingdecision was upheld by higher courts, most recently by the Federal ArbitrationArbitrazh Court of the Moscow District. The amount invalidated was used to set off subsequent tax liability.

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        In 2009, the tax authorities completed a tax audit of our subsidiary, Sibintertelecom, in respect of the years ended December 31, 2006, 2007 and 2008. As a result of the audit, the tax authorities imposed additional tax liability in the amount of 174.5 million rubles (approximately $5.8 million as of December 31, 2009), including taxes, fines and penalties. Sibintertelecom is currently appealingfiled a petition with the Arbitrazh Court of Moscow seeking to invalidate this assessment and in November 2010 the court ruled to invalidate the decision of the tax authorities. The court decision was further upheld by the Ninth Arbitrazh Appeal Court in February 2011. The tax authorities then appealed the latter decision to the Federal Arbitrazh Court of the Moscow District, which similarly upheld the decision.

        In 2010, the Russian tax authorities initiated an audit of our compliance with tax legislation for the years ended December 31, 2008 and 2007. Based on the results of this audit, the tax authorities

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imposed an additional tax liability in the amount of 353.9 million rubles (approximately $11.6 million as of December 31, 2010), including taxes, fines and penalties. We appealed this assessment with the Federal Tax Service, which ruled to partially invalidate the assessment. We have filed a higherpetition with a court in order to invalidate this tax authority.assessment in full. The sitting of the court is set to commence on April 26, 2012.

        Recently, the tax authorities conducted a field tax audit of MGTS for the years 2007-2008. After consideration of company objections, additional tax liability in the amount of 258.1 million rubles (including taxes, fines and penalties) was imposed on February 9, 2012.

        See also "Item 8. Financial Information—A. Consolidated Statements and Other Financial Information—7. Litigation—Tax Audits and Claims."

The implications of the tax system in Ukraine are uncertain and various tax laws are subject to different interpretations.

        Besides the new Tax Code, which came into force on January 1, 2011, Ukraine currently has a number of laws related to various taxes imposed by both central and regional authorities. Applicable taxes include value added tax or VAT,("VAT"), corporate income tax (profits tax), customs duties, payroll (social) taxes and other taxes. These tax laws have not been in force for significant periods of time compared to more developed market economies and are constantly changed and amended. Accordingly, few precedents regarding tax issues are available.

        Although the Ukrainian Constitution prohibits retroactive enforcement of any newly enacted tax laws and the Law on Taxation System specifically requires legislation to adopt new tax laws at least six months prior to them becoming effective, such rules have largely been ignored. In addition, tax laws are often vaguely drafted, making it difficult for us to determine what actions are required for compliance. For example, MTS-Ukraine believes that

        Furthermore, with the services rendered to its subscribers within the networks of foreign operators that serve as roaming partners for MTS-Ukraine are not subject to VAT. However, due to the ambiguityentry into force of the Ukrainiannew Tax Code of Ukraine (the "TCU"), there is uncertainty in regards to tax legislation,accounting of payments for the stateuse of computer software. As part of its business, MTS Ukraine purchases limited end-user rights for the use of computer software. Currently, there are no clear rules for the classification of the payments made by MTS Ukraine for these purchases. Under the TCU, these payments may be treated as payments for copyrights (royalties), as payments for intangible assets or as payments for fixed assets. Tax authorities of different levels have provided inconsistent tax clarifications on this matter. The tax rate applicable to these payments will vary according to their classification.

        Also, rules established by the TCU for recalculation of the input tax credit for non-current assets are unclear. As a result, the issue of how to recalculate the input tax credit for non-current assets purchased before January 1, 2011, remains unresolved. There are currently two contradictory clarifications from the tax authorities may conclude that VAT applies to these services. In such case, MTS-Ukraine will be obligated to payon this issue, but both do not comply with the VAT sums and penalties.existing law.

        Uncertain transfer pricing rules and their inconsistent application by the Ukrainian tax authorities and courts may also adversely affect MTS-Ukraine'sMTS Ukraine's operations. MTS-Ukraine'sMTS Ukraine's transactions with its related parties as well as certain transactions with non-Ukrainian entities that are not MTS-Ukraine'sMTS Ukraine's related parties may be affected by the application of the transfer pricing rules. No "safe harbor" margin is provided under Ukrainian legislation if the sale price deviates from the arm's length price.

        Due to the poor quality of the applicable tax legislation and its inconsistent interpretation, it is possible that MTS-Ukraine'sMTS Ukraine's prices could be subject to challenge and adjustment for corporate income tax or VAT purposes. Profit repatriation arrangements, such as the level of royalties for trademarks or loan interest paid by MTS-UkraineMTS Ukraine from Ukraine abroad, may also be challenged for the same reasons. If such price adjustments are implemented, MTS-Ukraine'sMTS Ukraine's effective tax rate may increase and its financial results may be adversely affected.

        The recent significant increase in the radio frequency resource duty and increases in the Pension Fund duty payable by mobile telecommunications operators may also negatively affect the financial performanceTable of MTS-Ukraine.Contents

        Differing opinions regarding the legal interpretation of tax laws often exist both among and within governmental ministries and organizations, including the tax administration, creating uncertainties and areas of conflict for taxpayers and investors. In practice, the Ukrainian tax authorities tend to interpret the tax laws in an arbitrary way that rarely favors taxpayers.

        Tax declarations/returns, together with other legal compliance areas (e.g., customs and currency control matters), may be subject to review and investigation by various administrative divisions of the tax authorities, which are authorized by law to impose severe fines, penalties and interest charges. These circumstances create tax risks in Ukraine substantially more significant than typically found in countries with more developed tax systems. Generally, tax declarations/returns in Ukraine remain open and subject to inspection for a three-year period. However, this term may not be observed or may be

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