Washington, D.C. 20549

(Commission File Number) 0-30270

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PART I. FINANCIAL INFORMATION

ITEM 1. Financial Statements and Accompanying Notes

CROMPTON CORPORATION AND SUBSIDIARIES
Condensed Consolidated Statements of Earnings (Unaudited)
First quarter ended March 31, 2005 and 2004
(In thousands of dollars, except per share data)

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CROMPTON CORPORATION AND SUBSIDIARIES
Condensed Consolidated Balance Sheets
March 31, 2005 (Unaudited) and December 31, 2004
(In thousands of dollars)

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CROMPTON CORPORATION AND SUBSIDIARIES
Condensed Consolidated Statements of Cash Flows (Unaudited)
First quarter ended March 31, 2005 and 2004
(In thousands of dollars)

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CROMPTON CORPORATION AND SUBSIDIARIES
Notes to Condensed Consolidated Financial Statements (Unaudited)

The information in the foregoing condensed consolidated financial statements for the first quarter ended March 31, 2005 and March 31, 2004 is unaudited, but reflects all adjustments that are of a normal recurring nature, which in the opinion of management, are necessary for a fair presentation of the results of operations for the interim periods presented. The foregoing condensed consolidated financial statements include the accounts of Crompton Corporation and its wholly-owned and majority owned subsidiaries, which are collectively referred to as "the Company." Other affiliates in which the Company has a 20% to 50% ownership are accounted for in accordance with the equity method.

As a result of the agreement to sell the Refined Products business to Sun Capital Partners Group, Inc. announced on March 18, 2005, the accompanying condensed consolidated financial statements reflect the Refined Products business as a discontinued operation. The operations of the Refined Products business have been classified as earnings from discontinued operations (net of tax) and the estimated carrying amount of the assets being sold and of the liabilities being transferred have been reflected as assets and liabilities held for sale for all periods presented. The condensed consolidated statements of cash flows have not been adjusted to reflect the discontinued operation and thus include the cash flows of the Refined Products business for all periods presented. Refer to the discontinued operations footnote for further information.

Certain financial information and footnote disclosures included in the annual financial statements have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission for reporting on Form 10-Q. The interim consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company's 2004 Annual Report on Form 10-K. The consolidated results of operations for the three months ended March 31, 2005 are not necessarily indicative of the results expected for the full year.

Cost of products sold includes all costs incurred in manufacturing products, including raw materials, direct manufacturing costs and manufacturing overhead. Cost of products sold also includes warehousing, distribution, engineering (other than polymer processing equipment design engineering), purchasing, customer service and environmental, health and safety functions, and shipping costs for outbound product shipments. Selling, general and administrative expenses (SG&A) include costs and expenses related to the following functions and activities: selling, advertising, polymer processing equipment design engineering, information technology, legal, provision for doubtful accounts, corporate facilities and corporate administration. SG&A also includes accounting, finance and human resources, excluding direct support in manufacturing operations, which is included as cost of products sold. Research and development expenses (R&D) include basic and applied research and development activities of a technical and non-routine nature. R&D costs are expensed as incurred. Costs of products sold, SG&A and R&D expenses exclude depreciation and amortization expenses, which are presented on a separate line in the condensed consolidated statements of earnings.

Included in cost of products sold are shipping costs of $15.7 million and $16.7 million for the first quarters ended March 31, 2005 and March 31, 2004, respectively.

Included in the Company's condensed consolidated balance sheets at March 31, 2005 and December 31, 2004, is approximately $15 million and $20 million, respectively, of restricted cash that is required to be on deposit to support certain letters of credit and performance guarantees, the majority of which will be settled within one year. In addition, at March 31, 2005, the Company had approximately $58.2 million in a cash collateral account that is restricted to pay current and future litigation liabilities, including related legal costs.

Included in accounts receivable are allowances for doubtful accounts of $22.6 million at March 31, 2005 and $22.3 million at December 31, 2004.

Accumulated depreciation amounted to $854.3 million at March 31, 2005 and $835.6 million at December 31, 2004.

Certain reclassifications have been made to the prior year condensed consolidated statement of earnings, including the reclassification of shipping costs from SG&A to cost of products sold to provide comparability to other entities in the Company's business sector.

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As permitted under Financial Accounting Standards Board (FASB) Statements No. 123, "Accounting for Stock-Based Compensation" and No. 148, "Accounting for Stock-Based Compensation - Transition and Disclosure," the Company elected to continue its historical method of accounting for stock-based compensation in accordance with Accounting Principles Board Opinion (APB) No. 25, "Accounting for Stock Issued to Employees." Under APB 25, compensation expense for fixed plans is recognized based on the difference between the exercise price and the stock price on the date of grant. Since the Company's fixed plan awards have been granted with an exercise price equal to the stock price on the date of grant, no compensation expense has been recognized in the statement of operations for these awards. However, compensation expense has been recognized for the restricted stock awards under the Company's long-term incentive programs in accordance with the provisions of APB 25, which would be unchanged under FASB Statements No. 123 and No. 148. In December 2004, the FASB issued Statement No. 123 (revised 2004), "Share-Based Payment", which replaces FASB Statement No. 123 and supercedes APB Opinion No. 25. FASB Statement No. 123 (revised 2004) requires all share-based payments to employees, including grants of employee stock options, to be recognized in the financial statements based on their fair value, beginning with the first interim period after June 15, 2005. On April 14, 2005, the Securities and Exchange Commission announced that the effective date of Statement No. 123 (revised 2004) will be suspended until the beginning of the first fiscal year beginning after June 15, 2005. The Company is in the process of reviewing the accounting impact of these awards under FASB Statement No. 123 (revised 2004).

The following table illustrates the effect on net earnings (loss) and related per share amounts as if the Company had applied the fair value recognition provisions of Statements No. 123 and No. 148 to all stock-based employee compensation awards.

During the first quarter of 2004, the Company appointed a new President and CEO, and the former Chairman, President and CEO; Senior Vice President and CFO; and certain other executives elected to retire. As a result of this reorganization, the Company completed the separation agreements for the former Chairman, President and CEO, Senior Vice President and CFO, and other executives and recorded a pre-tax charge of $2.8 million for severance and related costs in 2004. During the first quarter of 2005, the Company reversed $0.2 million of the 2004 charge to adjust for reserves no longer deemed necessary. Payments and non-cash activity related to this charge were $1.1 million during 2004 and $0.4 million during the first quarter of 2005. The remaining reserve balance at March 31, 2005 was $1.1 million.

In 2004, the Company completed an activity-based restructuring initiative, including a voluntary severance program, intended to structure the Company's operations in a more efficient and cost effective manner. As a result of the voluntary program, 137 U.S. based employees voluntarily elected to terminate their employment. In addition, the Company is in the process of involuntarily terminating approximately 500 worldwide employees as a result of the activity-based restructuring initiative, of which approximately 439 have been terminated as of March 31, 2005. During 2004, the Company recorded pre-tax charges of $54 million for facility closures, severance and related costs. The Company recorded additional charges during the first quarter of 2005 of $2.3 million. The related reserve activity is as follows:

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