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.

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted 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 such files).

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

If an emerging growth company, 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 is a shell company (as defined in Rule 12b-2 of the Exchange Act).

At March 31,June 30, 2021, 935.51 shares of common stock were outstanding, all of which were held by the registrant’s parent, The Dow Chemical Company.

The registrant meets the conditions set forth in General Instruction H(1)(a) and (b) for Form 10-Q and is therefore filing this form with a reduced disclosure format.

Throughout this Quarterly Report on Form 10-Q, except as otherwise indicated by the context, the terms "Corporation" or "UCC" as used herein mean Union Carbide Corporation and its subsidiaries.

Certain statements in this report are "forward-looking statements" within the meaning of federal securities laws, including Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Such statements often address expected future business and financial performance, financial condition, and other matters and often contain words or phrases such as “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “opportunity,” “outlook,” “plan,” “project,” “seek,” “should,” “strategy,” “target,” “will,” “will be,” “will continue,” “will likely result,” “would” and similar expressions, and variations or negatives of these words or phrases.

Forward-looking statements are based on current assumptions and expectations of future events that are subject to risks, uncertainties and other factors that are beyond the Corporation’s control, which may cause actual results to differ materially from those projected, anticipated or implied in the forward-looking statements and speak only as of the date the statements were made. These factors often address expected future business and financial performance and financial condition, including, but not limited to: the continuing global and regional economic impacts of the coronavirus disease 2019 pandemic and other public health-related risks and events on the Corporation’s business; and developments related to contemplated restructuring activities and proposed divestitures or acquisitions such as workforce reduction, manufacturing facility and/or asset closure and related exit and disposal activities, and the benefits and costs associated with each of the foregoing.

Where, in any forward-looking statement, an expectation or belief as to future results or events is expressed, such expectation or belief is based on the current plans and expectations of management and expressed in good faith and believed to have a reasonable basis, but there can be no assurance that the expectation or belief will result or be achieved or accomplished. A detailed discussion of principal risks and uncertainties which may cause actual results and events to differ materially from such forward-looking statements is included in the section titled "Risk Factors" in Part I, Item 1A of the Corporation's Annual Report on Form 10-K for the fiscal year ended December 31, 2020. These are not the only risks and uncertainties that the Corporation faces. There may be other risks and uncertainties that the Corporation is unable to identify at this time or that it does not currently expect to have a material impact on its business. If any of those risks or uncertainties develops into an actual event, it could have a material adverse effect on the Corporation’s business. The Corporation assumes no obligation to update or revise publicly any forward-looking statements whether because of new information, future events, or otherwise, except as required by securities and other applicable laws.

The unaudited interim consolidated financial statements of Union Carbide Corporation and its subsidiaries (the "Corporation" or "UCC") were prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") and reflect all adjustments (including normal recurring accruals) which, in the opinion of management, are considered necessary for the fair presentation of the results for the periods presented. These statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2020 ("2020 10-K").

The Corporation is a wholly owned subsidiary of The Dow Chemical Company ("TDCC"). In accordance with the accounting guidance for earnings per share, the presentation of earnings per share is not required in financial statements of wholly owned subsidiaries.

The Corporation’s business activities comprise components of TDCC’s global operations rather than stand-alone operations. TDCC conducts its worldwide operations through global businesses. Because there are no separate reportable business segments for UCC under the accounting guidance related to segment reporting and no detailed business information is provided to a chief operating decision maker regarding the Corporation’s stand-alone operations, the Corporation’s results are reported as a single operating segment.

Intercompany transactions and balances are eliminated in consolidation. Transactions with the Corporation’s parent company, TDCC, and other subsidiaries of TDCC, have been reflected as related company transactions in the consolidated financial statements. See Note 11 for additional information.

In the first quarter of 2021, the Corporation adopted Accounting Standards Update 2019-12, "Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes." The amendments simplify the accounting for income taxes by removing certain exceptions to the general principles of Topic 740, "Income Taxes" and improve consistent application by clarifying and amending existing guidance. The adoption of this guidance did not have a material impact on the consolidated financial statements.

Substantially all of the Corporation's revenue is generated by sales to TDCC. Products are sold to and purchased from TDCC at prices determined in accordance with the terms of an agreement between UCC and TDCC. The Corporation's revenue related to sales of product was approximately 96 percent and 97 percent for the three and six months ended June 30, 2021, respectively (98 percent and 99 percent for the three and six months ended March 31, 2021 (99 percent for the three months ended March 31, 2020)June 30, 2020, respectively); the remaining revenue primarily related to the licensing of patents and technology. The Corporation sells its products to TDCC to simplify the customer interface process.

The Corporation’s contract liabilities include payments received in advance of performance under long-term contracts for product sales and royalties with remaining contract terms that range up to 20 years. Amounts are recognized in revenue when the performance obligations for the contract are met. The Corporation has rights to additional consideration when product is delivered to the customer. The balance of contract liabilities was $40$39 million at March 31,June 30, 2021 ($40 million at December 31, 2020), of which $5 million ($5 million at December 31, 2020) was included in "Accrued and other current liabilities" and $35$34 million ($35 million at December 31, 2020) was included in "Other noncurrent obligations" in the consolidated balance sheets.

The Corporation disaggregates its revenue from contracts with customers by type of customer (sales to related parties and sales to trade customers) as presented in the consolidated statements of income and believes this disaggregation best depicts the nature, amount, timing and uncertainty of its revenue and cash flows. Substantially all of the product sales are made to the Corporation's parent company, TDCC, and there are no unique economic factors that affect revenue recognition and cash flows associated with these product sales.

Total estimated amortization expense for 2021 and the five succeeding fiscal years, including amounts expected to be capitalized, is as follows:

A summary of the Corporation's commitments and contingent liabilities can be found in Note 14 to the Consolidated Financial Statements included in the 2020 10-K, which is incorporated by reference herein.

Accruals for environmental matters are recorded when it is probable that a liability has been incurred and the amount of the liability can be reasonably estimated, based on current law and existing technologies. At March 31,June 30, 2021, the Corporation had accrued obligations of $142$141 million for probable environmental remediation and restoration costs, including $19 million for the remediation of Superfund sites. These obligations are included in "Accrued and other current liabilities" and "Other noncurrent obligations" in the consolidated balance sheets. This is management’s best estimate of the costs for remediation and restoration with respect to environmental matters for which the Corporation has accrued liabilities, although it is reasonably possible that the ultimate cost with respect to these particular matters could range up to approximately two and a half times that amount. Consequently, it is reasonably possible that environmental remediation and restoration costs in excess of amounts accrued could have a material impact on the Corporation's results of operations, financial condition and cash flows. It is the opinion of the Corporation’s management that the possibility is remote that costs in excess of the range disclosed will have a material impact on the Corporation’s results of operations, financial condition and cash flows. Inherent uncertainties exist in these estimates primarily due to unknown environmental conditions, changing governmental regulations and legal standards regarding liability, and emerging remediation technologies for handling site remediation and restoration. As new or additional information becomes available and/or certain spending trends become known, management will evaluate such information in determination of the current estimate of the environmental liability. At December 31, 2020, the Corporation had accrued obligations of $133 million for probable environmental remediation and restoration costs, including $18 million for the remediation of Superfund sites.

Each quarter, the Corporation reviews claims filed, settled and dismissed, as well as average settlement and resolution costs by disease category. The Corporation also considers additional quantitative and qualitative factors such as the nature of pending claims, trial experience of the Corporation and other asbestos defendants, current spending for defense and processing costs, significant appellate rulings and legislative developments, trends in the tort system, and their respective effects on expected future resolution costs. UCC management considers these factors in conjunction with the most recent actuarial study and determines whether a change in the estimate is warranted. Based on the Corporation's review of 2021 activity, it was determined that no adjustment to the accrual was required at March 31,June 30, 2021.

The Corporation’s total asbestos-related liability for pending and future claims and defense and processing costs was $1,080$1,060 million at March 31,June 30, 2021 ($1,098 million at December 31, 2020), and was included in “Asbestos-related liabilities - current” and “Asbestos-related liabilities - noncurrent” in the consolidated balance sheets. At March 31,June 30, 2021, approximately 24 percent of the recorded claim liability related to pending claims and approximately 76 percent related to future claims.

For additional information on the Corporation's leases, see Note 15 to the Consolidated Financial Statements included in the 2020 10-K.

The components of lease cost for operating and finance leases for the three and six months ended March 31,June 30, 2021 and 2020 were as follows:

The following table provides supplemental cash flow information related to leases:

The following table summarizes the lease-related assets and liabilities recorded in the consolidated balance sheets at March 31,June 30, 2021 and December 31, 2020:

The weighted-average remaining lease term and discount rate for leases recorded in the consolidated balance sheets at March 31,June 30, 2021 and December 31, 2020 are provided below:

The changes in the balances for each component of accumulated other comprehensive loss ("AOCL") for the three and six months ended March 31,June 30, 2021 and 2020 were as follows:

A summary of the Corporation's pension and other postretirement benefit plans can be found in Note 17 to the Consolidated Financial Statements included in the 2020 10-K.

On March 4, 2021, TDCC announced changes to the design of its U.S. tax-qualified and non-qualified pension plans, including the plans of the Corporation (the “UCC Plans”). Effective December 31, 2023 (“Effective Date”), the Corporation will freeze the pensionable compensation and credited service amounts used to calculate pension benefits for employees who participate in the UCC Plans. As a result, at the Effective Date and subject to any bargaining obligations required by law, active participants of the UCC Plans will not accrue additional benefits for future service and compensation. Additionally, contributions to U.S. tax-qualified and non-qualified defined contribution plans will be harmonized across the U.S. eligible employee population of TDCC and its consolidated subsidiaries. The new matching contribution, beginning January 1, 2022, will allow all eligible U.S. employees to receive matching contributions of up to 5 percent of their eligible compensation. In addition, beginning on January 1, 2024, all eligible U.S. employees will receive an automatic non-elective contribution of 4 percent of eligible compensation to their respective defined contribution plans.

The Corporation's funding policy is to contribute to pension plans when pension laws and/or economics either require or encourage funding. On March 4, 2021, the Corporation elected to contribute $545 million to its tax-qualified pension plan, funded by the Corporation's notes receivable from TDCC, and, as a result, increased its estimated total 2021 pension contributions to approximately $550 million, of which $547$548 million has been contributed through March 31,June 30, 2021.

In connection with the foregoing plan amendments, the Corporation remeasured the UCC Plans effective February 28, 2021, which resulted in a pretax actuarial gain of $87 million, reflected in other comprehensive income and inclusive of a $14 million reduction in the projected benefit obligation resulting from the plan amendments, and a pretax curtailment gain of $7 million, recognized in the first quarter of 2021.

The following table provides the components of the Corporation's net periodic benefit cost (credit) for all significant plans:

Net periodic benefit cost (credit), other than the service cost component, is included in "Sundry income (expense) - net" in the consolidated statements of income.

The Corporation's financial instruments are classified as Level 2 measurements. For assets and liabilities classified as Level 2 measurements, where the security is frequently traded in less active markets, fair value is based on the closing price at the end of the period; where the security is less frequently traded, fair value is based on the price a dealer would pay for the security or similar securities, adjusted for any terms specific to that asset or liability, or by using observable market data points of similar, more liquid securities to imply the price. Market inputs are obtained from well-established and recognized vendors of market data and subjected to tolerance and quality checks.

The following table summarizes the fair value of the Corporation's financial instruments at March 31,June 30, 2021 and December 31, 2020:

Cost approximates fair value for all other financial instruments.

A summary of the Corporation's related party transactions can be found in Note 19 to the Consolidated Financial Statements included in the 2020 10-K.

The following table summarizes UCC’s transactions with TDCC and a TDCC subsidiary related to product and services agreements for the three and six months ended March 31,June 30, 2021 and 2020:

The following table summarizes cash dividends declared and paid to TDCC for the three and six months ended March 31,June 30, 2021 and 2020:

Plaintiffs' lawyers often sue numerous defendants in individual lawsuits or on behalf of numerous claimants. As a result, the damages alleged are not expressly identified as to UCC, Amchem or any other particular defendant, even when specific damages are alleged with respect to a specific disease or injury. In fact, there are no personal injury cases in which only the Corporation and/or Amchem are the sole named defendants. For these reasons and based upon the Corporation's litigation and settlement experience, the Corporation does not consider the damages alleged against it and Amchem to be a meaningful factor in its determination of any potential asbestos-related liability.

For additional information, see Asbestos-Related Matters in Note 6 to the Consolidated Financial Statements and Note 14 to the Consolidated Financial Statements included in the 2020 10-K, and Part II, Item 1. Legal Proceedings.

The Corporation’s outstanding public debt has been issued under indentures which contain, among other provisions, covenants that the Corporation must comply with while the underlying notes are outstanding. Such covenants are typically based on the Corporation’s size and financial position and include, subject to the exceptions and qualifications contained in the indentures, obligations not to (i) allow liens on principal U.S. manufacturing facilities, (ii) enter into sale and lease-back transactions with respect to principal U.S. manufacturing facilities, or (iii) merge into or consolidate with any other entity or sell or convey all or substantially all of its assets. Failure of the Corporation to comply with any of these covenants could, after the passage of any applicable grace period, result in a default under the applicable indenture which would allow the note holders to accelerate the due date of the outstanding principal and accrued interest on the subject notes. Management believes the Corporation was in compliance with the covenants referred to above at March 31,June 30, 2021.

On a quarterly basis, the Corporation's Board of Directors (the "Board") reviews and determines if there will be a dividend distribution to its parent company and sole shareholder, TDCC. The Board takes into consideration the level of earnings and cash flows, among other factors, in determining the amount of the dividend distribution. Based on these factors, the Board did not declare a cash dividend to TDCC in the second quarter of 2021. For the first six months of 2021, the Corporation declared and paid cash dividends of $40 million to TDCC. In the firstsecond quarter of 2021,2020, the Corporation declared and paid a cash dividend of $40$81 million to TDCC ($81162 million infor the first quartersix months of 2020). On July 20, 2021, the Board approved a dividend to TDCC of $78 million, payable on or before September 24, 2021.

As of the end of the period covered by this Quarterly Report on Form 10-Q, the Corporation carried out an evaluation, under the supervision and with the participation of the Corporation's Disclosure Committee and the Corporation's management, including the Chief Executive Officer and the Chief Financial Officer, of the effectiveness of the design and operation of the Corporation's disclosure controls and procedures pursuant to paragraph (b) of Exchange Act Rules 13a-15 and 15d-15. Based upon that evaluation, the Chief Executive Officer and the Chief Financial Officer concluded that the Corporation's disclosure controls and procedures were effective.

There were no changes in the Corporation's internal control over financial reporting identified in connection with the evaluation required by paragraph (d) of Exchange Act Rules 13a-15 and 15d-15 that was conducted during the last fiscal quarter that have materially affected, or are reasonably likely to materially affect, the Corporation's internal control over financial reporting.

No material developments in asbestos-related matters occurred in the first quartersix months of 2021. For a current status of asbestos-related matters, see Note 6 to the Consolidated Financial Statements.