As filed with the Securities and Exchange Commission on April 30, 201929, 2021

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form20-F

(Mark One)

OR

For the fiscal year ended December 31, 20182020

OR

OR

Date of event requiring this shell company report            

For the transition period from             to            

Commission file number1-13368

POSCO

(Exact name of Registrant as specified in its charter)

POSCO Center, 440Teheran-ro,Gangnam-gu

Seoul, Republic of Korea 06194

(Address of principal executive offices)

Lim,Sung-SuSohn, Kyle

POSCO Center, 440Teheran-ro,Gangnam-gu

Seoul, Republic of Korea 06194

Telephone:+82-2-3457-1098;82-2-3457-1386;E-mail: s2blue@posco.com;sohnkangil@posco.com; Facsimile:+82-2-3457-1997

(Name, telephone,e-mail and/or facsimile number and address of company contact person)

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

Securities registered or to be registered pursuant to Section 12(g) of the Act.

None

Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act.

None

As of December 31, 2018,2020, there were 80,001,13276,015,472 shares of common stock, par value Won 5,000 per share, outstanding

(not including 7,185,70311,171,363 shares of common stock held by the company as treasury shares)

Indicate by check mark if the registrant is awell-known seasoned issuer, as defined in Rule 405 of the Securities Act.Yes  ☒        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.Yes  ☐        No   ☒

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.Yes  ☒        No   ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of RegulationS-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).Yes  ☒        No   ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer or an emerging growth company. See definition of “large accelerated filer,” “accelerated filer” and “emerging growth company” in Rule12b-2 of the Exchange Act. (Check one):

Large accelerated filer☒        Accelerated filer☐        Non-accelerated filer☐        Emerging growth company☐

If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.    Yes  ☒No   ☐

Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing.U.S. GAAP  ☐        IFRS  ☒         Other  ☐

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.Item 17  ☐         Item 18  ☐

If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule12b-2 of the Exchange Act).Yes  ☐             No  ☒

TABLE OF CONTENTS

i

ii

GLOSSARY

Any discrepancies in any table between totals and the sums of the amounts listed are due to rounding.

PART I

Item 1.Identity of Directors, Senior Managers and Advisers

Item 1.A.  Directors and Senior Management

Not applicable

Item 1.B.Advisers

Not applicable

Item 1.C.Auditor

Not applicable

Item 2.  Offer Statistics and Expected Timetable

Not applicable

Item 2.A.  Offer Statistics

Not applicable

Not applicable

Item 3.  Key Information

The selected financial data presented below should be read in conjunction with our Consolidated Financial Statements and related notes thereto and “Item 5. Operating and Financial Review and Prospects” included elsewhere in this annual report. The selected financial data in Won as of December 31, 20172019 and 20182020 and for each of the years in thethree-year period ended December 31, 20182020 were derived from our Consolidated Financial Statements included elsewhere in this annual report. Our Consolidated Financial Statements are prepared in accordance with IFRS as issued by the IASB.

In addition to preparing financial statements in accordance with IFRS as issued by the IASB included in this annual report, we prepare financial statements in accordance with Korean International Financial Reporting Standards(“K-IFRS”) as adopted by the Korean Accounting Standards Board (the “KASB”), which we are required to file with the Financial Services Commission and the Korea Exchange under the FSCMA. English translations of such financial statements are furnished to the SEC under Form6-K.K-IFRS6-K. K-IFRS differs in certain respects from IFRS as issued by the IASB in the presentation of operating profit. Additionally,For example, underK-IFRS, revenue from the development and sale of certain real estate is recognized using the percentage of completion method. However, under IFRS as issued by the IASB, revenue from the development and sale of real estate is recognized when an individual unit of residential real estate is delivered to the buyer. As a result, our consolidated statements of comprehensive income and our consolidated statements of financial position prepared in accordance with IFRS as issued by the IASB included in this annual report differ from our consolidated statements of comprehensive income and consolidated statements of financial position prepared in accordance withK-IFRS. See “Item 5.A. Operating Results — Explanatory Note Regarding Presentation of Certain Financial Information underK-IFRS.”

The information set forth below is not necessarily indicative of the results of future operations and should be read in conjunction with “Item 5. Operating and Financial Review and Prospects” and our consolidated financial statements and related notes included in this annual report.

Selected consolidated statement of comprehensive income data

Selected consolidated statements of financial position data

Selected consolidated statements of cash flows data

Item 3.B.  Capitalization and Indebtedness

Not applicable

Item 3.C.  Reasons for Offer and Use of Proceeds

Not applicable

Item 3.D.  Risk Factors

You should carefully consider the risks described below.

The global economic downturn may adversely affect our business and performance. The global economic outlook for the near future remains uncertain.

Our business is affected by highly cyclical market demand for our steel products from a number of industries, including the construction, automotive, shipbuilding and electrical appliances industries as well as downstream steel processors, which are sensitive to general conditions in the global economy. Macroeconomic factors, such as the economic growth rate, employment levels, interest rates, inflation rates, exchange rates, commodity prices, demographic trends and fiscal policies of governments can have a significant effect on such industries. From time to time, these industries have experienced significant and sometimes prolonged downturns, which in turn have negatively impacted our steel business. Global economic conditions have deteriorated in recent years, with global financial and capital markets experiencing substantial volatility. In particular, the ongoing global pandemic of a new strain of coronavirus (“COVID-19”) has materially and adversely affected the global economy and financial markets starting in early 2020. See “— Earthquakes, tsunamis, floods, severe health epidemics (including the ongoing global COVID-19 pandemic and any possible recurrence of other types of widespread infectious diseases) and other natural calamities could materially adversely affect our business, results of operations or financial condition.” Such developments have also been caused by, and continue to be exacerbated by, among other things, the slowdown of economic growth in China and other major emerging market economies, adverse economic and political conditions in Europe and Latin America and continuing geopolitical and social instability in North Korea and various parts of the Middle East, as well as uncertainty regarding the timing and method of the United Kingdom’s exit from the European Union (“Brexit”), and a deterioration in economic and trade relations between the United States and its major trading partners, including China, Canada and Mexico.particularly China.

An actual or anticipated further deterioration of global economic conditions may result in a decline in demand for our products that could haveproducts. In the case of a negative impact on the prices at which they can be sold. In such a case, we will likely face pressure to reduce prices andprolonged decrease in demand, we may need to rationalize our production capacity and reduce fixed costs. In the past,costs, and we will likely face pressure to reduce prices of our products. From time to time, we have adjusted our crude steel production levels and sales prices in response to sluggish demand from our customers in industries adversely impacted by the deteriorating economic conditions. In particular, the global recession exacerbated by COVID-19 and the resulting decline in demand for steel products have adversely affected the overall sales volume of our principal steel products produced by us and directly sold to external customers in 2020 compared to 2019 as well as our sales prices. We produced 42.242.9 million tons of crude

The World Health Organization declared the COVID-19 as a pandemic in March 2020. While we do not believe that such disruptions and arrangements have had a material adverse impact on our business, a prolonged outbreak of COVID-19 may result in further disruptions in the normal operations of our business, including disruptions in the operation of our production facilities, delays in our production facility expansion projects, implementation of further work arrangements requiring employees to work remotely and restrictions on overseas and domestic business travel, which may lead to a reduction in labor productivity.

Other risks associated with prolonged outbreak of COVID-19 or other types of widespread infectious disease include:

It is not possible to predict the duration or full magnitude of harm from COVID-19. In the event that COVID-19 or other types of widespread infectious diseases cannot be effectively and timely contained, our business, financial condition and results of operations may be materially adversely affected.

Korea is our most important market, and our current business and future growth could be materially and adversely affected if economic conditions in Korea deteriorate.

We are incorporated in Korea, and a substantial portion of our operations and assets are located in Korea. Korea is our most important market, accounting for 38.4%38.6% of our total revenue from steel products produced and sold by us in 2018.2020. Domestic demand for our products is affected by the condition of major steel consuming industries, such as construction, shipbuilding, automotive, electrical appliances and downstream steel processors, and the Korean economy in general. In addition, the trading operations of POSCO International Corporation (“POSCO International” and formerly known as POSCO Daewoo Corporation)) are affected by the general level of trade between Korea and other countries, which in turn tends to fluctuate based on

general conditions in the Korean and global economies. As a result, we are subject to political, economic, legal and regulatory risks specific to Korea, and our performance and successful fulfillment of our operational strategies are largely dependent on the overall Korean economy. The economic indicators in Korea in recent years have shown mixed signs, and future growth of the Korean economy is subject to many factors beyond our control, including developments in the global economy.

In recent years,particular, the on-going COVID-19 pandemic has had an adverse conditions and volatility in the worldwide financial markets, fluctuations in oil and commodity prices and the general weakness of the global economy have contributed to the uncertainty of global economic prospects in general and have adversely affected, and may continue to adversely affect,impact on the Korean economy. The valueFollowing the Government’s announcement of the Won relativefirst confirmed case of COVID-19 in Korea in January 2020, it has implemented a number of measures in order to major foreign currencies has also fluctuated significantly and, as a result of changing global and Korean economic conditions, there has been volatility incontain the stock prices of Korean companies in recent years. Future declines in the Korea Composite Stock Price Index (the “KOSPI”) and large amounts of sales of Korean securities by foreign investors and subsequent repatriationspread of the proceedsCOVID-19 disease, including a nationwide order for social distancing, implementation of such salesstrict self-isolation and quarantine measures for those who may adversely affectbe infected, and the valuetemporary closure of all school and other public facilities. In addition, the Government has undertaken a series of actions to mitigate the adverse impact of the Won,COVID-19 pandemic on the foreignKorean economy, including (i) lowering of The Bank of Korea’s policy rates, (ii) execution of a bilateral currency reserves held byswap agreement with the U.S. Federal Reserve, (iii) provision of loans, guarantees and maturity extensions to eligible financial institutions, in Koreasmall- and medium business enterprises and self-employed business owners facing liquidity crises; (iv) offering emergency relief payments for those impacted by the ability of Korean companies to raise capital. Any future deteriorationCOVID-19 pandemic; and (v) establishment of the Key Industry Stabilization Fund in May 2020 to support businesses in certain key industries, such as the air transport and maritime industries. However, the impact of the on-going COVID-19 pandemic to the Korean or global economy could adversely affect our business, financial conditionin 2021 and results of operations.for the foreseeable future remains highly uncertain.

DevelopmentsOther developments that could have an adverse impact on Korea’s economy include:

Economic weakness in Asia may also adversely affect our sales to the Korean companies that export to the region, especially companies in the construction, shipbuilding, automotive, electrical appliances and downstream steel processing industries. Weaker demand in these countries, combined with an increase in global production capacity, may also reduce export prices in Dollar terms of our principal products sold to customers in Asia. For a discussion of productionover-capacity in the global steel industry, see “— We operate in the highly competitive steel, trading and construction industries, and our failure to successfully compete would adversely affect our market position and business.” We attempt to maintain and expand our export sales to generate foreign currency receipts to cover our foreign currency purchases and debt service requirements. Consequently, any decrease in our export sales could also increase our foreign exchange risks.

Depreciation of the value of the Won against the Dollar and other major foreign currencies may have a material adverse effect on the results of our operations and on the price of the ADSs.

Our consolidated financial statements are prepared from our local currency denominated financial results, assets and liabilities and our subsidiaries around the world, which are then translated into Won. A substantial proportion of our consolidated financial results is accounted for in currencies other than the Won. Accordingly, our consolidated financial results and assets and liabilities may be materially affected by changes in the exchange rates of foreign currencies. In 2018, 61.6%2020, 61.4% of our total revenue from steel products produced and sold by us was in overseas markets outside of Korea. To the extent that we incur costs in one currency and make sales in another, our profit margins may be affected by changes in the exchange rates between the two currencies. Since the currency in which sales are recorded may not be the same as the currency in which expenses are incurred, foreign

exchange rate fluctuations is partially mitigated by such strategies, we and our subsidiaries, particularly POSCO International and POSCO Engineering & Construction Co., Ltd. (“POSCO E&C”), also periodically enter into derivative contracts, primarily foreign currency swaps and forward exchange contracts, to further hedge some of our foreign exchange risks. However, our results of operations have historically been affected by exchange rate fluctuations and there can be no assurance that such strategies will be sufficient to reduce or eliminate the adverse impact of such fluctuations in the future.

Fluctuations in the exchange rate between the Won and the Dollar will also affect the Dollar equivalent of the Won price of the shares of our common stock on the KRX KOSPIKorea Composite Stock Price Index (the “KOSPI”) Market and, as a result, will likely affect the market price of the ADSs. These fluctuations will also affect the Dollar conversion by the depositary for the ADRs of cash dividends, if any, paid in Won on shares of common stock represented by the ADSs.

We are dependent on imported raw materials, and significant increases in market prices of essential raw materials could adversely affect our margins and profits.

We purchase substantially all of the principal raw materials we use from sources outside Korea, including iron ore and coal. POSCO imported approximately 5451 million dry metric tons of iron ore and 2927 million wet metric tons of coal in 2018. 2020.Iron ore is imported primarily from Australia, Brazil and Canada. Coal is imported primarily from Australia, Canada and Russia. Although we have not experienced significant unanticipated supply disruptions in the past, supply disruptions, which could be caused by political or other events in the countries from which we import these materials, could adversely affect our operations. In addition, we are particularly exposed to increases in the prices of coal, iron ore and nickel, which represent the largest components of our cost of goods sold. The prices

industry, which in turn has led the Chinese government to pursue aggressive consolidation in the Chinese steel industry, such as the consolidation of Baosteel Group and Wuhan Iron and Steel in 2016, that has resulted in fewer but larger steel manufacturers that are able to compete more effectively in the global steel industry. In addition, the global steel industry has experienced consolidation in the past, including through the mergers of Mittal and Arcelor in 2006 and Nippon Steel and Sumitomo Metal in 2012.past. Competition from such global steel manufacturers with expanded production capacity as well as competitors from emerging markets, especially from China and India, has resulted in significant price competition and may result in declining margins and reductions in revenue in the future. Our larger competitors may use their resources, which may be greater than ours, against us in a variety of ways, including by making additional acquisitions, investing more aggressively in product development and capacity and displacing demand for our export products.

In the past, increasedIncreased production capacity, combined with decreased demand resulting from a slowdown of the global economy, has from time to time resulted in productionover-capacity in the global steel industry which in turn has resulted in downward pressure on global steel prices. For example,Such production over-capacity in the global steel prices decreasedindustry was exacerbated in the fourth quarter of 2018 in part2020 due to a decrease in demand from China as well as an increasecaused by the COVID-19 pandemic. Although demand for steel products has shown signs of recovery in select regions starting in the second half of 2020, production capacity of Chinese manufacturers that survived the consolidation of the Chinese steel industry. Productionover-capacity in global steel industry may intensify if global economic growthrecovery slows or demand from developing countries, particularly from China, continues to lag behind the growth in production capacity. Productionover-capacity in the global steel industry is likely to:

The overseas trading markets in which POSCO International operates are also highly competitive. POSCO International’s principal competitors in overseas trading markets include Korean trading companies that operate in various international markets, as well as foreign trading companies, particularly those based in Japan. As POSCO International diversifies into businesses other than traditional trading such as natural resources development, it also increasingly competes with other Korean and international companies involved in these businesses. Some of POSCO International’s competitors may be more experienced and have greater financial resources and pricing flexibility than POSCO International, as well as more extensive global networks and wider access to customers. There is no assurance that POSCO International will be able to continue to compete successfully in this economic environment or that the prolonged slowdown of the global economy will not have a material adverse effect on its business, results of operations or financial condition. In 2018, 2019 and 2020, we recognized impairment of goodwill of Won 158 billion, Won 55 billion and Won 189 billion, respectively, related to a decrease in value-in-use of POSCO International.

Construction.POSCO E&C, our consolidated subsidiary, operates in the highly competitive construction industry. Competition is based primarily on price, reputation for quality, reliability, punctuality and financial strength of contractors. Intense competition among construction companies may result in, among other things, a decrease in the price POSCO E&C can charge for its services, difficulty in winning bids for construction projects, an increase in construction costs and difficulty in obtaininghigh-quality contractors and qualified employees.

In Korea, POSCO E&C’s main competition in the construction of residential andnon-residential buildings, EPC (or engineering, procurement and construction) projects, urban planning and development projects and civil works projects consists of approximately ten major domestic

The success of our diversification strategy will depend, in part, on our ability to realize the anticipated growth opportunities and synergies. Some of our diversification efforts have not been successful. For example, in 2018, we incurred impairment loss of Won 810 billion in 2018 related to our synthetic natural gas production facility in Gwangyang due to our discontinuation of the business which we had launched in 2011, which was adversely impacted by a decline in the market price of liquefied natural gas (“LNG”). In 2019, we incurred impairment loss of Won 74 billion related to the discontinued operation of a ferrosilicon facility in Pohang and Won 70 billion related to the discontinued operation of a compact endless cast-rolling mill facility in Gwangyang. The realization of the anticipated benefits from our diversification efforts depends on numerous factors, some of which are outside our control, including the availability of qualified personnel, establishment of new relationships and expansion of existing relationships with various customers and suppliers, procurement of necessary technology andknow-how to engage in such businesses and decreases in the prices of competing products or services that make our products or services less competitive. The realization of the anticipated benefits may be impeded, delayed or reduced as a result of numerous factors, some of which are outside our control. These factors include:

Expansion of our trading, construction and production operations abroad requires management attention and resources. In addition, we face additional risks associated with our expansion outside Korea, including:

We have limited insurance coverage and may incur significant losses resulting from operating hazards, product liability claims from customers or business interruptions.

The normal operation of our manufacturing facilities may be interrupted by accidents caused by operating hazards, power supply disruptions and equipment failures, as well as natural disasters. As

We participate in overseas natural resources exploration, development and production projects, which expose us to various risks.

As part of our efforts to diversify our operations, we carefully seek out promising overseas natural resources exploration, development and production opportunities. For instance, we purchased lithium mining rights at the Salar del Hombre Muerto salt flat in northern Argentina in August 2018 for $280 million. We also participate in natural resources projects as part of consortia or through acquisitions of minority interests, such as a gas field exploration project in Myanmar through POSCO International. We may also selectively acquire or invest in companies or businesses that engage in such activities. To the extent that we enter into these arrangements, our success in these endeavors will depend in part on the willingness of our partner companies to dedicate sufficient resources to their partnership with us, as well as our ability to finance such investments.

The demand and market acceptance for such activities abroad are subject to a substantially higher level of uncertainty than our traditional steel business and are substantially dependent upon the market condition of the global natural resources industry as well as the political and social environment of the target countries. The performance of projects in which we participate may be adversely affected by the occurrence of military hostility, political unrest or acts of terrorism. For example, in February 2021, Myanmar’s military declared a state of emergency for a year with detention of Myanmar’s national adviser Aung San Suu Kyi and senior members of the ruling party’s National League for Democracy. See Note 41(b) to the Consolidated Financial Statements. In addition, some of our current exploration, development and production projects involve drilling exploratory wells on properties with no proven amount of natural resource reserves. Although all drilling, whether developmental or exploratory, involves risks, exploratory drilling involves greater risks of dry holes or failure to find commercial quantities of natural resources. Other risks to which such activities are subject include obtaining required regulatory approvals and licenses, securing and maintaining

Any of these and other factors may have a material adverse effect on the performance of our joint projects and expose us to a number of risks, including the risk that the partners may be incapable of providing the required financial support to the partnerships and the risk that the partners may not be able to fulfill their other obligations, resulting in disputes not only between our partners and us, but also between the joint ventures and their customers. Such a material adverse effect on the performance of our joint projects may in turn materially and adversely affect our business, results of operations and financial condition.

Cyclical fluctuations based on macroeconomic factors may adversely affect POSCO E&C’s business and performance.

We engage in engineering and construction activities through POSCO E&C. The Construction Segment is highly cyclical and tends to fluctuate based on macroeconomic factors, such as consumer confidence and income, employment levels, interest rates, inflation rates, demographic trends and policies of the Government. From time to time, the construction industry has experienced significant and sometimes prolonged downturns, and our construction revenues have fluctuated in the past

reduced or eliminated. For example, we incurred losses in recent years in connection with a delay in the construction ofCSP-Companhia Siderurgia do Pecem steel plant complex in Brazil. If POSCO E&C experiences significant unforeseen additional expenses with respect to its fixed price projects, it may incur losses on such projects, which could have a material adverse effect on its financial condition and results of operations.

We are subject to environmental regulations, and our operations could expose us to substantial liabilities.

We are subject to national and local environmental laws and regulations, including increasing pressure to reduce emission of carbon dioxide relating to our manufacturing process, and our steel manufacturing and construction operations could expose us to risk of substantial liability relating to environmental or health and safety issues, such as those resulting from discharge of pollutants and carbon dioxide into the environment, the handling, storage and disposal of solid or hazardous materials or wastes and the investigation and remediation of contaminated sites. We may be responsible for the investigation and remediation of environmental conditions at currently and formerly operated manufacturing or construction sites. For example, we incurred expenses in recent years relating to contamination of land near our magnesium smelting plant located in Gangneung, Korea and gas treatment plant located in our Pohang Works. We may also be subject to associated liabilities, including liabilities for natural resource damage, third party property damage or personal injury resulting from lawsuits brought by the Government or private litigants. In the course of our operations,

Failure to protect our intellectual property rights could impair our competitiveness and harm our business and future prospects.

We believe that developing new steel manufacturing technologies that can be differentiated from those of our competitors, such as FINEX, automotive steel manufacturing technology andhigh-manganese steel manufacturing technology, is critical to the success of our business.Webusiness.We take active measures to obtain protection of our intellectual property by obtaining patents and undertaking monitoring activities in our major markets. However, we cannot assure you that the measures we take will effectively deter competitors from improper use of our proprietary technologies. Our competitors may misappropriate our intellectual property, disputes as to ownership of intellectual property may arise and our intellectual property may otherwise become known or independently developed by our competitors. Any failure to protect our intellectual property could impair our competitiveness and harm our business and future prospects.

We rely on trade secrets and other unpatented proprietaryknow-how to maintain our competitive position, and unauthorized disclosure of our trade secrets or other unpatented proprietaryknow-how could negatively affect our business.

We rely on trade secrets and unpatented proprietaryknow-how and information. We enter into confidentiality agreements with each of our employees and consultants upon the commencement of an employment or consulting relationship. These agreements generally provide that all inventions, ideas, discoveries, improvements and patentable material made or conceived by the individual arising out of the employment or consulting relationship and all confidential information developed or made known to the individual during the term of the relationship is our exclusive property. We cannot assure the enforceability of these types of agreements, or that they will not be breached. We also cannot be certain that we will have adequate remedies for any breach. The disclosure of our trade secrets or otherknow-how as a result of such a breach could adversely affect our business.

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

We may be exposed to potential claims for unpaid wages and become subject to additional labor costs arising from the Supreme Court of Korea’s interpretation of ordinary wages.

Under the Labor Standards Act, an employee’s “ordinary wage” is used as the basis for calculating various statutory benefits. Prior to the Supreme Court of Korea’s decision described below, we and other companies in Korea had interpreted the previous guidelines issued by the Ministry of Employment and Labor as excluding fixed bonuses that are paid other than on a monthly basis, such as bi monthly, quarterly or biannually paid bonuses, from employees’ ordinary wages.

OnIn December 18, 2013, the Supreme Court of Korea ruled that regularly paid bonuses, including those that are paid other than on a monthly basis, are included in the scope of employees’ ordinary wages if these bonuses are paid (i) “regularly,” (ii) “uniformly” and (iii) on a “fixed basis,” notwithstanding differential amounts based on seniority. Under this decision, any provision of a collective bargaining agreement or other agreements that attempt to exclude such regular bonuses from employees’ ordinary wages will be deemed void for violation of the mandatory provisions of Korean law.

The Supreme Court of Korea’s decision clarified that if payment of a regular bonus is limited only to those working for the employer on a specific date, such bonus is not fixed and thus does not constitute part of an employee’s ordinary wage. The Ministry of Employment and Labor subsequently published guidelines onin January 23, 2014 (the “Guidelines”). According to the Guidelines, the Government excludes, from ordinary wages, regular bonuses contingent on employment on a specific date. Based on the Supreme Court of Korea’s decision and the Guidelines, we believe that regular bonuses we have paid to our employees are likely not required to be included in their ordinary wages because we have paid regular bonuses only to those working for us on the date of payment calculation, the 15th day of each month. However, if we are nonetheless determined to have underpaid

North Korea’s economy also faces severe challenges, which may further aggravate social and political pressures within North Korea.

Although bilateral summit meetings were held between Korea and North Korea in April, May and September 2018 and between the United States and North Korea in June 2018, February 2019 and FebruaryJune 2019, there can be no assurance that the level of tensions affecting the Korean peninsula will not escalate in the future. Any increase in tensions, which may occur, for example, if North Korea experiences a leadership crisis,high-level contacts between Korea or the United States and North Korea break down or further military hostilities occur, could have a material adverse effect on the Korean economy and on our business, financial condition and results of operations and the market value of our common stock and ADSs.

If you surrender your ADRs to withdraw shares of our common stock, you may not be allowed to deposit the shares again to obtain ADRs.

Under the deposit agreement, holders of shares of our common stock may deposit those shares with the ADR depositary’s custodian in Korea and obtain ADRs, and holders of ADRs may surrender

depositary, however, is not required to make available to you any rights to purchase any additional shares unless it deems that doing so is lawful and feasible and:

We are under no obligation to file any registration statement under the Securities Act to enable you to exercise preemptive rights in respect of the common shares underlying the ADSs, and we cannot assure you that any registration statement would be filed or that an exemption from the registration requirement under the Securities Act would be available. Accordingly, if a registration statement is required for you to exercise preemptive rights but is not filed by us, you will not be able to exercise your preemptive rights for additional shares and may suffer dilution of your equity interest in us.

U.S. investors may have difficulty enforcing civil liabilities against us and our directors and senior management.

We are incorporated in Korea with our principal executive offices located in Seoul. The majority of our directors and senior management are residents of jurisdictions outside the United States, and the majority of our assets and the assets of such persons are located outside the United States. As a result, U.S. investors may find it difficult to effect service of process within the United States upon us or such persons or to enforce outside the United States judgments obtained against us or such persons in U.S. courts, including actions predicated upon the civil liability provisions of the U.S. federal securities laws. It may also be difficult for an investor to enforce in U.S. courts judgments obtained against us or such persons in courts in jurisdictions outside the United States, including actions predicated upon the civil liability provisions of the U.S. federal securities laws. It may also be difficult for a U.S. investor to bring an action in a Korean court predicated upon the civil liability provisions of the U.S. federal securities laws against our directors and senior management andnon-U.S. experts named in this annual report.

investments do not involve any U.S. goods or services.Our activities in Iran and Cuba accounted for approximately 0.5%0.3% of our consolidated revenues in 2016, 0.6%2018, 0.01% in 20172019 and 0.3%0.00005% in 2018.2020. POSCO Coated & Color Steel also holds a 70% interest in Myanmar POSCO C&C Co., Ltd. (“Myanmar POSCO C&C”), a joint venture with Myanma Economic Holdings Public Company Limited that was designated as a U.S. Sanctions Target by OFAC on March 25, 2021. Myanmar POSCO C&C engages in the production and sale of coated steel roofing sheets in Myanmar, and its sales accounted for approximately 0.03% of our consolidated revenues in 2018, 0.04% in 2019 and 0.05% in 2020. POSCO Coated & Color Steel is currently reassessing the future of this joint venture.

We expect to continue to engage in business activities and make investments in countries that are deemed Sanctions Targets over the foreseeable future. Although we believe that OFAC Sanctions under their current terms are not applicable to our current activities, our reputation may be adversely affected, and some of our U.S. investors may be required to divest their investments in us under the laws of certain U.S. states or under internal investment policies or may decide for reputational reasons to divest such investments. We are aware of initiatives by U.S. governmental entities and U.S. institutional investors, such as pension funds, to adopt or consider adopting laws, regulations or policies prohibiting transactions with or investment in, or requiring divestment from, entities doing business with countries identified as state sponsors of terrorism. We cannot assure you that the foregoing will not occur or that such occurrence will not have a material adverse effect on the value of our securities.

Uncertainty relating to benchmark regulation reforms may adversely affect our securities linked to a benchmark.

The London Interbank Offered Rate (“LIBOR”) and the Euro Interbank Offered Rate (“EURIBOR”) and other indices which are deemed to be “benchmarks” are the subject of recent national, international and other regulatory guidance and proposals for reform. Some of these reforms are already effective while others have yet to be implemented. These reforms may cause such benchmarks to perform differently than in the past, or to disappear entirely, or have other consequences which cannot be predicted. Any such consequence could have a material adverse effect on any securities linked to such benchmarks.

Regulation (EU) 2016/1011 (the “Benchmark Regulation”) was published in the Official Journal of the European Union on June 29, 2016 and has been in force since January 1, 2018. The Benchmark Regulation applies to the provision of benchmarks, the contribution of input data to a benchmark and the use of a benchmark, within the European Union. Among other things, (i) it requires benchmark administrators (such as ICE Benchmark Administration Limited and the European Money Market Institute, which currently administer LIBOR and EURIBOR, respectively) to be authorized or registered (or, if non-European Union based, to be subject to an equivalent regime or otherwise recognized or endorsed) and (ii) it prevents certain uses by European Union-supervised entities of benchmarks of administrators that are not authorized or registered (or, if non-European Union based, not deemed equivalent or recognized or endorsed). In March 2021, the U.K. Financial Conduct Authority (the “FCA”), which has regulatory authority with respect to LIBOR, announced that all LIBOR settings will either cease to be provided by any administrator or no longer be representative (i) after December 31, 2021 in the case of all Sterling, Euro, Swiss Franc and Japanese Yen settings and the one-week and two-month Dollar settings and (ii) after June 30, 2023 in the case of remaining Dollar settings. While the ICE Benchmark Administration may publish certain LIBOR settings on the basis of a synthetic methodology for “tough legacy” contracts, there is no guarantee that such rates will be determined and published after the announced deadlines nor confirmed to be representative by the FCA.

The Benchmark Regulation could have a material impact on any securities linked to a rate or index deemed to be a benchmark, in particular, if the methodology or other terms of the benchmark are changed in order to comply with the requirements of the Benchmark Regulation. Such changes could, among other things, have the effect of reducing, increasing or otherwise affecting the volatility of the published rate or level of the benchmark. More broadly, any of the international, national or other

proposals for reform, or the general increased regulatory scrutiny of benchmarks, could increase the costs and risks of administering or otherwise participating in the setting of a benchmark and complying with any such regulations or requirements.

Such factors may have the following effects on certain benchmarks: (i) discourage market participants from continuing to administer or contribute to such benchmark; (ii) trigger changes in the rules or methodologies used in the benchmarks or (iii) lead to the disappearance of the benchmark. Any of the above changes or any other consequential changes as a result of international, national or other proposals for reform or other initiatives or investigations, could have a material adverse effect on the value of and return on any securities linked to a benchmark. Moreover, if a benchmark ceases to be calculated or administered and no replacement base rate is identified or selected, the fallback provisions for the interest rate calculations under the securities may result in interest accruing at a fixed rate based on the rate which applied in the previous period when the benchmark was available, effectively converting the securities into fixed rate securities.

U.S. investors could be subject to adverse U.S. federal income tax consequences if we are treated as a passive foreign investment company (“PFIC”) for any taxable year during which they hold our common stock of ADSs.

We will be classified as a PFIC for U.S. federal income tax purposes if, for any taxable year, either (i) 75 percent or more of our gross income for the taxable year is passive income or (ii) at least 50 percent of the average gross quarterly value of our assets is attributable to assets that produce or are held for the production of passive income. The determination of whether we are a PFIC must be made annually based on the facts and circumstances at the relevant time, some of which may be beyond our control, including the valuation of our assets as implied by the market price for our common stock or ADSs. Accordingly, it is possible that we could become a PFIC.

If we were to be classified as a PFIC in any taxable year during which a U.S. holder (as defined in “Item 10.E. Taxation — United States Taxation”) holds our common stock or ADSs, such U.S. holder could be subject to a special tax at ordinary income rates on “excess distributions,” including certain distributions by us and gain that the U.S. holder recognizes on the sale of our common stock or ADSs. The amount of income tax on any excess distributions would be increased by an interest charge to compensate for tax deferral, calculated as if the excess distributions were earned ratably over the period the U.S. holder held the common stock or ADSs. See “Item 10.E. Taxation — United States Taxation — Shares of Common Stock and ADSs — Passive Foreign Investment Company Rules.”

This annual report contains“forward-looking statements” that are subject to various risks and uncertainties.

This annual report contains“forward-looking statements” that are based on our current expectations, assumptions, estimates and projections about our company and our industry. Theforward-looking statements are subject to various risks and uncertainties. Theseforward-looking statements include, but are not limited to, those statements using words such as “anticipate,” “believe,” “continues,” “expect,” “estimate,” “intend,” “project,” “aim,” “plan,” “likely to,” “target,” “contemplate,” “predict,” “potential” and similar expressions and future or conditional verbs such as “will,” “would,” “should,” “could,” “might,” “can,” “may,” or similar expressions generally intended to identify forward-looking statements. Those statements include, among other things, the discussions of our business strategy and expectations concerning our market position, future operations, margins, profitability, liquidity and capital resources. We caution you that reliance on anyforward-looking statement involves risks and uncertainties, and that although we believe that the assumptions on which ourforward-looking statements are based are reasonable, any of those assumptions could prove to be inaccurate, and, as a result, theforward-looking statements based on those assumptions could be

forward-looking statements. We do not undertake to release the results of any revisions of theseforward-looking statements to reflect future events or circumstances.

Item 4.  Information on the Company

Item 4.A.  History and Development of the Company

We were established by the Government on April 1, 1968, under the Commercial Code, to manufacture and distribute steel rolled products and plates in the domestic and overseas markets. The Government owned more than 70% of our equity until 1988, when the Government reduced its ownership of our common stock to 35% through a public offering and listing our shares on the KRX KOSPI Market. In December 1998, the Government sold all of our common stock it owned directly, and The Korea Development Bank completed the sale of our shares that it owned in September 2000. The Government no longer holds any direct interest in us, and our outstanding common stock is currently held by individuals and institutions. See “Item 7. Major Shareholders and Related Party Transactions — Item 7A. Major Stockholders.”

Our legal and commercial name is POSCO. Our principal executive offices are located at POSCO Center, 440Teheran-ro,Gangnam-gu, Seoul, Korea 06194, and our telephone number is+82-2-3457-0114. +82-2-3457-0114. The address of our English website ishttp://www.posco.com.

The SEC maintains a website (http://www.sec.gov), which contains reports, information statements and other information regarding issuers that file electronically with the SEC.

Item 4.B.  Business Overview

The Company

We are the largest fully integrated steel producer in Korea, and one of the largest steel producers in the world, based on annual crude steel production. We produced approximately 42.940.6 million tons of crude steel and stainless steel in 2018,2020, a substantial portion of which was produced at Pohang Works and Gwangyang Works. As of December 31, 2018,2020, we had approximately 47.645.3 million tons of annual crude steel and stainless steel production capacity, including 17.640.7 million tons of production capacity of Pohang Works and 24.8 million tons of production capacity of Gwangyang Works.Wein Korea.We believe Pohang Works and Gwangyang Works are two of the most technologically advanced integrated steel facilities in the world. We manufacture and sell a diversified line of steel products, including cold rolled and hot rolled products, stainless steel products, plates, wire rods and silicon steel sheets, and we are able to meet a broad range of customer needs from manufacturing industries that consume steel, including automotive, shipbuilding, home appliance, engineering and machinery industries.

Korea is our most important market. Domestic sales accounted for 38.4%38.6% of our total revenue from steel products produced and sold by us in 20182020 and 39.0%37.3% in 2017.2019. On anon-consolidated basis, we believe that our steel products constituted approximately 50%51% of the total sales volume of such steel products sold in Korea in 20182020 and approximately 44%48% in 2017. 2019.Our export sales and overseas sales to customers abroad accounted for 61.6%61.4% of our total revenue from steel products produced and sold by us in 20182020 and 61.0%62.7% in 2017.2019. Our major export market is Asia, with China accounting for 28.9%35.8%, Asia other than China and Japan accounting for 23.4%20.4%, and Japan accounting for 10.3%9.3% of our total steel export revenue from steel products produced and exported by us in 20182020, and China accounting for 28.5%29.3%, Asia other than China and Japan accounting for 23.3%22.5%, and Japan accounting for 11.3%10.8% of our total steel export revenue from steel products produced and exported by us in 2017.2019.

planning, design and construction of industrial plants and architectural works and civil engineering. POSCO Energy Corporation is the largest private power generation company in Korea.

We generated revenue of Won 65,15557,467 billion and profit of Won 1,9321,748 billion in 2018,2020, compared to revenue of Won 60,18764,786 billion and profit of Won 2,9092,038 billion in 2017.2019. We had total assets of Won 78,77779,684 billion and total equity of Won 46,67347,604 billion as of December 31, 2018,2020, compared to total assets of Won 79,78679,371 billion and total equity of Won 47,32747,763 billion as of December 31, 2017.2019.

Major Products

We manufacture and sell a broad line of steel products, including the following:

The table below sets out our revenue of steel products produced by us and directly sold to external customers (either by us or through POSCO Processing & Service Co., Ltd. (“POSCO P&S”), our former subsidiary that primarily engaged in sales of steel products produced by us prior to the transfer of its steel product sales business to POSCO International in March 2017) which are recognized as external revenue of the Steel Segment, by major steel product categories for the periods indicated.Suchindicated. Such amounts do not include steel products produced by us and sold to our consolidated subsidiaries (including POSCO International) other than POSCO P&S. Although our external revenue of the Steel Segment increased in 2017 compared to 2016 and 2018 compared to 2017, they were negatively impacted in 2017 and 2018 by the recognition of the external revenue of POSCO P&S’s steel product sales business under the Trading Segment commencing March 2017 following the transfer of such business to POSCO International..

The table below sets out our sales volume of the principal categories of steel products produced by us and directly sold to external customers, (either by us or through POSCO P&S prior to the transfer

In addition to steel products produced by us and directly sold to external customers, (either by us or through POSCO P&S prior to the transfer of its steel product sales business to POSCO International in March 2017), we engage our consolidated sales subsidiaries (including POSCO International) to sell our steel products produced by us. Our revenue from steel products produced by us and sold to our consolidated sales subsidiaries that in turn sold them to their external customers amounted to Won 6,403 billion in 2016, Won 7,385 billion in 2017 and Won 7,492 billion in 2018.2018, Won 7,740 billion in 2019 and Won 7,018 billion in 2020. Sales of such steel products by our consolidated sales subsidiaries to external customers are recognized as external revenue of the Trading Segment.

Cold Rolled Products

Cold rolled coils and further refined galvanized cold rolled products are used mainly in the automotive industry to produce car body panels. Other users include the household goods, electrical appliances, engineering and metal goods industries.

Our deliveries of cold rolled products produced by us and directly sold to external customers amounted to 12.310.3 million tons in 2018,2020, representing 39.2%35.4% of our total sales volume of principal steel products produced by us and directly sold to external customers.

Cold rolled products constitute our largest product category in terms of sales volume and revenue from steel products produced by us and directly sold to external customers. In 2018,2020, our sales volume of cold rolled products produced by us and directly sold to external customers increaseddecreased by 9.1%7.6% compared to our sales volume in 20172019 primarily due to an increasedecreases in sales of cold rolled products manufactured and sold by our Chinese subsidiaries.subsidiaries in Mexico, India and Thailand as a result of the ongoing global COVID-19 pandemic.

Including sales of cold rolled products produced by us and sold through our consolidated sales subsidiaries in addition to cold rolled products produced by us and directly sold to external customers, we believe we had a domestic market share for cold rolled products of approximately 61%64% on anon-consolidated basis in 2018.2020.

Hot Rolled Products

Hot rolled coils and sheets have many different industrial applications. They are used to manufacture structural steel used in the construction of buildings, industrial pipes and tanks, and

Stainless Steel Products

Stainless steel products are used to manufacture household goods and are also used by the chemical industry, paper mills, the aviation industry, the automotive industry, the construction industry and the food processing industry.

Our deliveries of stainless steel products produced by us and directly sold to external customers amounted to 2.93.0 million tons in 2018,2020, representing 9.1%10.2% of our total sales volume of principal steel products produced by us and directly sold to external customers.

Stainless steel products constitute our second largest product category in terms of revenue from steel products produced by us and directly sold to external customers. Although sales of stainless steel products accounted for only 9.1%10.2% of total sales volume of the principal steel products produced by us and directly sold to external customers in 2018,2020, they represented 20.5%23.5% of our total revenue from steel products in 2018.2020. In 2018,2020, our sales volume of stainless steel products produced by us and directly sold to external customers decreasedincreased by 0.8%0.6% compared to our sales volume in 2017, in part2019 primarily due to a decreasean increase in demand from the automotive industry.sales of stainless steel products manufactured and sold by POSCO (Zhangjiagang) Stainless Steel Co., Ltd. (“POSCO (Zhangjiagang)” and formerly known as Zhangjiagang Pohang Stainless Steel Co., Ltd.).

Including sales of stainless steel products produced by us and sold through our consolidated sales subsidiaries in addition to stainless steel products produced by us and directly sold to external customers, we believe we had a domestic market share for stainless steel products of approximately 40%41% on anon-consolidated basis in 2018.2020.

Plates

Plates are used in shipbuilding, structural steelwork, offshore oil and gas production, power generation, mining, and the manufacture ofearth-moving and mechanical handling equipment, boiler and pressure vessels and other industrial machinery.

Our deliveries of plates produced by us and directly sold to external customers amounted to 5.04.8 million tons in 2018,2020, representing 15.8%16.3% of our total sales volume of principal steel products produced by us and directly sold to external customers. The Korean shipbuilding industry, which uses plates to manufacture chemical tankers, rigs, bulk carriers and containers, and the construction industry are our largest customers of plates.

In 2018,2020, our sales volume of wire rods produced by us and directly sold to external customers decreased by 4.6%6.7% compared to 20172019 primarily due to decreasesa decrease in sales of our wire rods manufactured and sold by our subsidiaries in Vietnam and Japan.India as a result of the ongoing global COVID-19 pandemic.

Including sales of wire rods produced by us and sold through our consolidated sales subsidiaries in addition to wire rods produced by us and directly sold to external customers, we believe we had a domestic market share for wire rods of approximately 59%60% on anon-consolidated basis in 2018.2020.

Silicon Steel Sheets

Silicon steel sheets are used mainly in the manufacture of power transformers and generators and rotating machines.

Our deliveries of silicon steel sheets produced by us and directly sold to external customers amounted to 0.9 million tons in 2018,2020, representing 2.8%3.0% of our total sales volume of principal steel products produced by us and directly sold to external customers.

In 2018,2020, our sales volume of silicon steel sheets produced by us and directly sold to external customers increased by 1.7%8.6% compared to 20172019 primarily due to an increase in demand forsales of silicon steel sheets manufactured and sold by our subsidiaries in India.China.

Including sales of silicon steel sheets produced by us and sold through our consolidated sales subsidiaries in addition to silicon steel sheets produced by us and directly sold to external customers, we believe we had a domestic market share for silicon steel sheets of approximately 80% on anon-consolidated basis in 2018.2020.

Others

Other products include lowervalue-addedsemi-finishedvalue-added semi-finished products such as pig iron, billets, blooms and slab.

Markets

Korea is our most important market. Domestic sales represented 38.4%38.6% of our total revenue from steel products produced and sold by us in 2018.2020. Our export sales and overseas sales to