Exhibit (a)(1)(D)

Offer to Purchase for Cash

All Outstanding Shares of Common Stock

of

NUMERICAL TECHNOLOGIES, INC.

at

$7.00 Net Per Share

by

NEON ACQUISITION CORPORATION

a wholly owned subsidiary of

SYNOPSYS, INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT,

NEW YORK CITY TIME, ON THURSDAY, FEBRUARY 20, 2003,

UNLESS THE OFFER IS EXTENDED.

January 23, 2003

To Brokers, Dealers, Commercial Banks,

Trust Companies and Other Nominees:

We have been engaged by Neon Acquisition Corporation, a Delaware corporation (“Purchaser”) and a wholly owned subsidiary of Synopsys, Inc., a Delaware corporation (“Synopsys”), to act as Information Agent in connection with Neon Acquisition Corporation’s offer to purchase all of the outstanding shares of common stock, par value $0.0001 per share (the “Shares”), of Numerical Technologies, Inc., a Delaware corporation (the “Company”), at $7.00 per Share, net to the seller in cash, without interest thereon and less any required withholding taxes, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated January 23, 2003 (the “Offer to Purchase”) and in the related Letter of Transmittal (which, together with the Offer to Purchase, as amended or supplemented from time to time, collectively constitute the “Offer”). Please furnish copies of the enclosed materials to those of your clients for whom you hold Shares registered in your name or in the name of your nominee.

The Offer is subject to the conditions, among others, that (a) prior to the expiration of the Offer there have been validly tendered in the Offer and not properly withdrawn that number of Shares which, together with the number of Shares, if any, then beneficially owned by Synopsys or Purchaser, represents at least a majority of the total number of outstanding Shares on a fully diluted basis (which shall mean, as of any time, the number of Shares outstanding, together with all Shares which the Company may be required to issue pursuant to any then outstanding warrants, options, benefit plans or obligations or otherwise, whether or not vested or then exercisable) on the date Shares are accepted for payment, and (b) any waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, applicable to the purchase of Shares pursuant to the Offer or to the Merger (as defined below) or any similar national antitrust or competition laws or foreign investment regulations having expired or been terminated. The Offer is also subject to certain other terms and conditions set forth in Section 13 of the Offer to Purchase. The expiration date of the Offer is 12:00 midnight, New York City time, on Thursday, February 20, 2003, or if the Offer is extended, the latest time and date at which the Offer, as so extended by Purchaser, will expire (the “Expiration Date”).

Enclosed herewith are the following documents:

1.  Offer to Purchase, dated January 23, 2003;

2.  Letter of Transmittal to be used by stockholders of the Company in accepting the Offer and tendering Shares;

3.  Notice of Guaranteed Delivery;

4.  Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9;

5.  Letter to stockholders of the Company from the interim President and Chief Executive Officer of the Company, accompanied by the Company’s Solicitation/Recommendation Statement on Schedule 14D-9;

6.  A printed form of a letter that may be sent to your clients for whose account you hold Shares in your name or in the name of your nominee, with space provided for obtaining such clients’ instructions with regard to the Offer; and

7.  Return envelope addressed to the Depositary (as defined below).

The Offer is being made pursuant to a Merger Agreement (the “Merger Agreement”), dated as of January 12, 2003, among Synopsys, Purchaser and the Company, pursuant to which, after completion of the Offer and the satisfaction or waiver of certain conditions, Purchaser will be merged with and into the Company, with the Company as the surviving corporation (the “Merger”) and each issued and outstanding Share (other than Shares owned by Synopsys or the Company or any wholly owned subsidiary of Synopsys or the Company or held by stockholders who properly exercise dissenters’ rights) will, by virtue of the Merger and without any action on the part of the holder thereof, be canceled and converted into the right to receive an amount in cash, without interest, equal to the per Share price paid pursuant to the Offer upon the surrender of the certificate formerly representing such Share.

The Board of Directors of the Company has unanimously approved the Merger Agreement, the Offer and the Merger, determined that the Offer and the Merger are advisable and fair to, and in the best interests of, the holders of Shares and unanimously recommends that stockholders accept the Offer and tender their Shares pursuant to the Offer and approve the Merger Agreement.

Upon the terms and subject to the conditions of the Offer (including, if the Offer is extended or amended, the terms and conditions of any such extension or amendment), Purchaser will be deemed to have accepted for payment, and will pay for, all Shares validly tendered and not properly withdrawn by the Expiration Date if and when Purchaser gives oral or written notice to Computershare Trust Company of New York (the “Depositary”) of the Purchaser’s acceptance of the tenders of such Shares for payment pursuant to the Offer. Payment for Shares tendered and accepted for payment pursuant to the Offer will be made only after timely receipt by the Depositary of (a) certificates for such Shares or a Book-Entry Confirmation (as defined in the Offer to Purchase) with respect to such Shares pursuant to the procedures set forth in the Offer to Purchase, (b) a Letter of Transmittal (or facsimile thereof), properly completed and duly executed, with any required signature guarantees (or, in the case of a book-entry transfer, an Agent’s Message (as defined in the Offer to Purchase) in lieu of the Letter of Transmittal) and (c) any other documents required by the Letter of Transmittal. Accordingly, tendering stockholders may be paid at different times depending upon when certificates for Shares or Book-Entry Confirmations with respect to Shares are actually received by the Depositary. Under no circumstances will interest be paid on the purchase price for Shares, regardless of any extension of the Offer or any delay in payment for Shares.

The Offer is not being made to (nor will tenders be accepted from or on behalf of) holders of Shares in any jurisdiction in which the making or acceptance of the Offer would not be in compliance with the laws of such jurisdiction. However, Purchaser may, in its sole discretion, take such action as it may deem necessary to make the Offer in any such jurisdiction and extend the Offer to holders of Shares in such jurisdiction. Neither Purchaser nor Synopsys is aware of any jurisdiction in which the making of the Offer or the acceptance of Shares in connection therewith would not be in compliance with the laws of such jurisdiction. An envelope in which to return your instructions to us is enclosed. If you authorize tender of your Shares, all such Shares will be tendered unless otherwise indicated in such instruction form. Please forward your instructions to us as soon as possible to allow us ample time to tender Shares on your behalf prior to the expiration of the Offer.

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In order to tender Shares pursuant to the Offer, a properly completed and duly executed Letter of Transmittal (or facsimile thereof), with any required signature guarantees, or an Agent’s Message (in the case of any book-entry transfer), and any other documents required by the Letter of Transmittal, should be sent to and timely received by the Depositary, and either certificates representing the tendered Shares should be delivered or such Shares must be delivered to the Depositary pursuant to the procedures for book-entry transfers, all in accordance with the instructions set forth in the Letter of Transmittal and the Offer to Purchase.

Neither Synopsys nor Purchaser will pay any fees or commissions to any broker or dealer or other person (other than the Information Agent and the Depositary as described in the Offer to Purchase) in connection with the solicitation of tenders of Shares pursuant to the Offer. You will be reimbursed upon request for customary mailing and handling expenses incurred by you in forwarding the enclosed offering materials to your clients.

Your prompt action is requested. We urge you to contact your clients as promptly as possible. The Offer and withdrawal rights will expire at 12:00 midnight, New York City time, on Thursday, February 20, 2003, unless the Offer is extended.

If holders of Shares wish to tender their Shares, but it is impracticable for them to deliver their certificates representing tendered Shares or other required documents or to complete the procedures for delivery by book-entry transfer prior to the Expiration Date, a tender may be effected by following the guaranteed delivery procedures specified in the Offer to Purchase and the Letter of Transmittal.

Questions and requests for assistance or for additional copies of the enclosed materials may be directed to the Information Agent at the address and telephone number set forth below and in the Offer to Purchase. Additional copies of the enclosed materials will be furnished at Purchaser’s expense.

Very truly yours,

D. F. King & Co., Inc.

NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL RENDER YOU OR ANY PERSON THE AGENT OF PURCHASER, SYNOPSYS, THE COMPANY, THE INFORMATION AGENT, THE DEPOSITARY OR ANY OF THEIR AFFILIATES, OR AUTHORIZE YOU OR ANY OTHER PERSON TO USE ANY DOCUMENT OR MAKE ANY REPRESENTATION ON BEHALF OF ANY OF THEM WITH RESPECT TO THE OFFER NOT CONTAINED IN THE OFFER TO PURCHASE OR THE LETTER OF TRANSMITTAL.

The Information Agent for the Offer is:

D. F. King & Co., Inc.

77 Water Street

New York, NY 10005

Banks and Brokers Call Collect: (212) 269-5550

All Others Call Toll Free: (800) 628-8532

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