SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 -------------- FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 --------------- Date of Report (Date of earliest event reported) : May 28, 2002 CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES CORP. (as company under a Pooling and Servicing Agreement, dated as of April 1, 2002, providing for, inter alia, the issuance of CSFB Mortgage Pass-Through Certificates, Series 2001-S12) CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES CORP. (Exact name of registrant as specified in its charter) Delaware 333-77054 13-3320910 State or Other Jurisdiction (Commission (IRS Employer of Incorporation ) File Number) Identification No.) 11 Madison Ave. New York, New York 10010 (Address of Principal Executive Offices) (Zip Code) Registrant's telephone number, including area code :(212)538-3000 N/A (Former name or former address, if changed since last report.) Item 5. Other Events. This report and the attached exhibit is being filed with respect to the Registrant's CSFB Mortgage Pass-through Certificates, Series 2001-S12 (the "Certificates") pursuant to "no-action" positions taken by the Securities and Exchange Commission with respect to alternative means of satisfying the Registrant's reporting obligations under the Securities Exchange Act of 1934, as amended. The Certificates were issued, and this report and exhibit is being filed, pursuant to the terms of the Pooling and Servicing Agreement, dated as of April 1, 2002 among Credit Suisse First Boston Mortgage Securities Corp., as depositor, DLJ Mortgage Capital Inc., as seller, Wilshire Credit Corporation and Ocwen Federal Bank FSB as servicers, and JPMorgan Chase Bank, as trustee. On May 28, 2002 distributions were made to the Certificateholders. Specific information with respect to the distributions is filed as Exhibit 99.1. No other reportable transactions or matters have occurred during the current reporting period. Item 7. Financial Statements and Exhibits. (a) Not applicable. (b) Not applicable. (c) The following exhibits are filed as part of this report: Statement to Certificateholders on May 28, 2002 is filed as Exhibit 99.1 hereto. -2- <page> SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. JPMorgan Chase Bank, not in its individual capacity but solely as Trustee under the Agreement referred to herein Date: June 14, 2002 By: /s/ Andreas Auer ----------------------------------- Andreas Auer Assistant Vice President -3- <page> INDEX TO EXHIBITS Exhibit Number Description of Exhibits 99.1 Monthly Certificateholder Statement on May 28, 2002 -4- Exhibit 99.1 Monthly Certificateholder Statement on May 28, 2002 -5- <page> CSFB Mortgage Pass-Through Certificates, Series 2002-S12 Statement to Certificate Holders May 28, 2002 <s> <c> <c> - --------------------------------------------------------------------------------------------------------------------------------- DISTRIBUTION IN DOLLARS - --------------------------------------------------------------------------------------------------------------------------------- ORIGINAL BEGINNING FACE PRINCIPAL REALIZED DEFERRED PRINCIPAL CLASS VALUE BALANCE PRINCIPAL INTEREST TOTAL LOSSES INTEREST BALANCE - --------------------------------------------------------------------------------------------------------------------------------- A1 185,500,000.00 185,500,000.00 3,505,122.88 878,342.50 4,383,465.38 0.00 0.00 181,994,877.12 A2 163,000,000.00 163,000,000.00 3,079,973.20 327,222.50 3,407,195.70 0.00 0.00 159,920,026.80 A3 22,500,000.00 22,500,000.00 425,149.68 47,231.25 472,380.93 0.00 0.00 22,074,850.32 AR 100.00 100.00 100.00 0.94 100.94 0.00 0.00 0.00 M1 40,000,000.00 40,000,000.00 0.00 108,166.67 108,166.67 0.00 0.00 40,000,000.00 M2 38,500,000.00 38,500,000.00 0.00 134,108.33 134,108.33 0.00 0.00 38,500,000.00 B1A 7,750,000.00 7,750,000.00 0.00 30,903.13 30,903.13 0.00 0.00 7,750,000.00 B1B 7,750,000.00 7,750,000.00 0.00 35,520.83 35,520.83 0.00 0.00 7,750,000.00 P 100.00 100.00 0.00 64,802.26 64,802.26 0.00 0.00 100.00 TOTALS 465,000,200.00 465,000,200.00 7,010,345.76 1,626,298.41 8,636,644.17 0.00 0.00 457,989,854.24 X1 465,000,200.00 465,000,200.00 0.00 2,882,875.60 2,882,875.60 0.00 0.00 457,989,854.24 X2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 - --------------------------------------------------------------------------------------------------------------------------------- - ---------------------------------------------------------------------------------------------------------------------------------- FACTOR INFORMATION PER $1000 OF ORIGINAL FACE PASS-THROUGH RATES - --------------------------------------------------------------------------------------------------------- ---------------------- BEGINNING ENDING CURRENT CLASS CUSIP PRINCIPAL PRINCIPAL INTEREST TOTAL PRINCIPAL CLASS PASS-THRU RATE - --------------------------------------------------------------------------------------------------------- ---------------------- A1 22540VL42 1,000.00000000 18.89554113 4.73500000 23.63054113 981.10445887 A1 5.682000 % A2 22540VL59 1,000.00000000 18.89554110 2.00750000 20.90304110 981.10445890 A2 2.190000 % A3 22540VM66 1,000.00000000 18.89554133 2.09916667 20.99470800 981.10445867 A3 2.290000 % AR 22540VL67 1,000.00000000 1,000.00000000 9.40000000 1,009.40000000 0.00000000 AR 11.336279 % M1 22540VL75 1,000.00000000 0.00000000 2.70416675 2.70416675 1,000.00000000 M1 2.950000 % M2 22540VL83 1,000.00000000 0.00000000 3.48333325 3.48333325 1,000.00000000 M2 3.800000 % B1A 22540VL91 1,000.00000000 0.00000000 3.98750065 3.98750065 1,000.00000000 B1A 4.350000 % B1B 22540VM25 1,000.00000000 0.00000000 4.58333290 4.58333290 1,000.00000000 B1B 5.000000 % P 22540VM33 1,000.00000000 0.00000000 ##### #### 1,000.00000000 P 11.336279 % TOTALS 1,000.00000000 15.07600590 3.49741443 18.57342033 984.92399410 X1 22540VM41 1,000.00000000 0.00000000 6.19972981 6.19972981 984.92399410 X1 0.000000 % - --------------------------------------------------------------------------------------------------------- ------------------------ IF THERE, ARE ANY QUESTIONS OR PROBLEMS WITH THIS STATEMENT PLEASE CONTACT THE ADMINISTRATOR LISTED BELOW: Scott B. Rubin JPMorgan Chase Bank - Structured Finance Services 450 West 33rd St, 14th fl, New York, New York 10001 Tel: (212) 946-8847 Fax: (212) 946-8919 Email: scott.b.rubin@chase.com Copyright 2001 J.P. Morgan Chase & Co. All rights reserved. -6- Credit Suisse First Boston, Mortgage Pass-Through Certificates, Series 2002-S12 Statement to Certificate Holders May 28, 2002 Sec. 4.06(a)(i) Amounts Allocable to Principal Scheduled Principal 283,360.62 Principal Prepayments 6,283,825.91 Repurchase Principal 0.00 Curtailments 441,460.93 Curtailment Adjustments 1,698.30 Other Principal Adjustments 0.00 Liquidation Proceeds 0.00 Prepayment Penalties (distributed to the Class P Certificates) 64,801.32 Sec. 4.06(a)(ii) Sec. 4.06(a)(iv) Principal Balance of the Mortgage Loans Beginning Principal Balance of the Mortgage Loans 444,402,931.23 Ending Principal Balance of the Mortgage Loans 437,392,585.47 Sec. 4.06(a)(v) Servicing Fees 185,167.89 Trustee Fee 2,036.85 Credit Risk Manager Fee 6,480.88 FSA Premium 29,041.67 Prepayment Penalties 64,801.32 Sec. 4.06(a)(vii) Servicer Advances 0.00 Cumulative Servicer Advances 0.00 Sec. 4.06(a)(viii)(A) Number and Aggregate Principal Amounts of Mortgage Loans in Delinquency (Exclusive of Loans in Foreclosures) Group 1 Principal Category Number Balance Percentage 1 Month 16 706,085.02 0.16 % 2 Month 1 122,531.25 0.03 % 3 Month 3 80,379.76 0.02 % Total 20 908,996.03 0.21 % Group Totals Principal Category Number Balance Percentage 1 Month 16 706,085.02 0.16 % 2 Month 1 122,531.25 0.03 % 3 Month 3 80,379.76 0.02 % Total 20 908,996.03 0.21 % Sec. 4.06(a)(viii)(B) Number and Aggregate Principal Amounts of Mortgage Loans in Foreclosure Number of Loans in Foreclosure and Delinquent 31 to 60 days 0.00 Principal Balance of Loans in Foreclosure and Delinquent 31 to 60 days 0.00 Number of Loans in Foreclosure and Delinquent 61 to 90 days 0.00 Principal Balance of Loans in Foreclosure and Delinquent 61 to 90 days 0.00 Number of Loans in Foreclosure and Delinquent 91 or more days 0.00 Principal Balance of Loans in Foreclosure and Delinquent 91 or more days 0.00 Sec. 4.06(a)(xi) 60+ Delinquent Scheduled Payments - 12 Month Period This Period (1) 2,297.86 (2) 0.00 (3) 0.00 (4) 0.00 (5) 0.00 (6) 0.00 (7) 0.00 (8) 0.00 (9) 0.00 (10) 0.00 (11) 0.00 (12) 0.00 Sec. 4.06(a)(x) REO Loans - Loan Level Sec. 4.06(a)(xi) Number and Aggregate Principal Amounts of REO Loans Group 1 Principal Number Balance Percentage 0 0.00 0.00% Group Totals Principal Number Balance Percentage 0 0.00 0.00% Sec. 4.06(a)(xii) Current Realized Losses 0.00 Cumulative Realized Losses 0.00 Sec. 4.06(a)(xiii) Rolling Three Month Delinquency Rate 0.0443 Sec. 4.06(a)(xiv) Amount on Deposit in Pre-Funding Account 20,597,268.77 Capitalized Interest Requirement 73,057.44 Sec. 4.06(a)(xiv) Amount of Insured Payment 0.00 Additional Prepayment Net Interest 6,063.31 Servicing Fee on Additional Prepayment Net Interest 253.57 Prepayment Interest Shortfall Allocated to Class A-1 0.00 Prepayment Interest Shortfall Allocated to Class A-2 0.00 Prepayment Interest Shortfall Allocated to Class A-3 0.00 Prepayment Interest Shortfall Allocated to Class P 0.00 Prepayment Interest Shortfall Allocated to Class A-R 0.00 Prepayment Interest Shortfall Allocated to Class M-1 0.00 Prepayment Interest Shortfall Allocated to Class M-2 0.00 Prepayment Interest Shortfall Allocated to Class B-1A 0.00 Prepayment Interest Shortfall Allocated to Class B-1B 0.00 Total Prepayment Interest Shortfall Allocated 0.00 Overcollateralization Amount 0.00 Target Overcollateralization Amount 17,437,507.50 Overcollateralization Release Amount 0.00 Overcollateralization Increase Amount 0.00