WASHINGTON, DC 20549
                                   FORM 144
                                  ACT OF 1933
ATTENTION: Transmit for filing 3 copies of this form concurrently with
           either placing an order with a broker to execute sale or
           executing a sale directly with a market maker.

- ------------------------------------------------------------------------------------------------------------------------------------
 1(a) NAME OF ISSUER (Please type or print)                  (b) I.R.S. IDENT. NO.    (c) S.E.C. FILE NO.
      Martin Marietta Materials, Inc.                            56-1848578               1-12744
- ------------------------------------------------------------------------------------------------------------------------------------
 1(d) ADDRESS OF ISSUER                   STREET           CITY           STATE           ZIP CODE             (e) TELEPHONE NO.
      2710 Wycliff Road                                  Raleigh           NC              27607            AREA CODE      NUMBER
- ------------------------------------------------------------------------------------------------------------------------------------
      THE SECURITIES ARE TO BE SOLD                                TO ISSUER

      Jonathan T. Stewart                    ###-##-####           Officer            1408 Ridge Side Place Raleigh, NC  27613
- ------------------------------------------------------------------------------------------------------------------------------------
INSTRUCTION: The person filing this notice should contact the issuer to obtain the IRS Identification Number and the SEC File Number - ------------------------------------------------------------------------------------------------------------------------------ 3(a) (b) (c) (d) Title of the Name and Address of Each Broker SEC USE ONLY Number of Shares Aggregate Class of Through Whom the Securities are to be --------------- or Other Units Market Securities Offered or Each Market Maker who is Broker-Dealer To Be Sold Value To Be Sold Acquiring the Securities File Number (See instr. 3(C)) (See instr. 3(D)) - ------------------------------------------------------------------------------------------------------------------------------ Common Stock TD Waterhouse 23,364 1,238,292 100 Wall Street New York, NY 10005 - ------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------ (e) (f) (g) Number of Shares Approximate Name of Each or Other Units Date of Sale Securities Outstanding (See instr. 3(F)) Exchange (See instr. 3(E)) (MO. DAY YR.) (See instr. 3(G)) - --------------------------------------------------------------- 46,731,109 5/2/00 NYSE - --------------------------------------------------------------- - --------------------------------------------------------------- - --------------------------------------------------------------- INSTRUCTIONS: 1. (a) Name of issuer. (b) Issuer's IRS Identification Number. (c) Issuer's SEC file number, if any. (d) Issuer's address, including zip code. (e) Issuer's telephone number, including area code. 2. (a) Name of person for whose account the securities are to be sold. (b) Such person's IRS identification number, if such person is an entity. (c) Such person's relationship to the issuer (e.g., officer, director, 10% stockholder, or member of immediate family of any of the foregoing). (d) Such person's address, including zip code. 3. (a) Title of the class of securities to be sold. (b) Name and address of each broker through whom the securities are intended to be sold. (c) Number of shares or other units to be sold (if debt securities, give the aggregate face amount). (d) Aggregate market value of the securities to be sold as of a specified date within 10 days prior to the filing of this notice. (e) Number of shares or other units of the class outstanding, or if debt securities the face amount thereof outstanding, as shown by the most recent report or statement published by the issuer. (f) Approximate date on which the securities are to be sold. (g) Name of each securities exchange, if any, on which the securities are intended to be sold.
2 TABLE I--SECURITIES TO BE SOLD Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor: - --------------------------------------------------------------------------------------------------------------------------------- Name of Person from Whom acquired Amount of Title of Date You Nature of Acquisition (If gift, also give Securities Date of the Class Acquired Transaction date donor acquired) Acquired Payment Nature of Payment --------- -------- --------------------- -------------------- ---------- ------- ----------------- Common 4/28/00 Stock Options granted Martin Marietta 28,667 5/2/00 Check 1994, 1995, 1996, 1997 Materials, Inc. - --------------------------------------------------------------------------------------------------------------------------------- INSTRUCTIONS: 1. If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid. 2. If within two years after the acquisition of the securities the person for whose account they are to be sold had any short positions, put or other option to dispose of securities referred to in paragraph (d)(3) of Rule 144, furnish full information with respect thereto. - ------------------------------------------------------------------------------------------------------------------------------------ TABLE II--SECURITIES SOLD DURING THE PAST THREE MONTHS Furnish the following information as to all securities of the issuer sold during the past three months by the person for whose account the securities are to be sold. - ------------------------------------------------------------------------------------------------------------------------------------ Amount of Securities Name and Address of Seller Title of Securities Sold Date of Sale Sold Gross Proceeds -------------------------- ------------------------ ------------ ---------- -------------- 0 - ------------------------------------------------------------------------------------------------------------------------------------ REMARKS: INSTRUCTIONS: See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice. 5/2/00 ---------------------------------------- DATE OF NOTICE ATTENTION: The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. /s/ Jonathan T. Stewart ---------------------------------------- (SIGNATURE) Jonathan T. Stewart The notice shall be signed by the person for whose account the securities are to be sold. At least one copy of the notice shall be manually signed. Any copies not manually signed shall bear typed or printed signatures. ATTENTION: INTERNATIONAL MISSTATEMENTS OR OMISSION OF FACTS CONSTITUTE FEDERAL CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001).