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SILICON VALLEY BANK

                                  AMENDMENT TO

                               PURCHASE AGREEMENT

SELLER: SUPERCONDUCTOR TECHNOLOGIES INC.

DATED AS OF: APRIL 27, 2004

      THIS AMENDMENT TO PURCHASE AGREEMENT (THIS "AMENDMENT") is entered into
between SILICON VALLEY BANK ("Buyer") and Superconductor Technologies Inc.
("Seller").

      Reference is made to the Accounts Receivable Purchase Agreement between
Buyer, on the one side, and Seller, on the other side, and having an effective
date of June 23, 2003, as modified on March 17, 2004 (collectively the "Purchase
Agreement"). Unless otherwise defined herein, capitalized terms defined in the
Purchase Agreement are used herein as therein defined.

      Buyer and Seller hereby agree to modify the Purchase Agreement as follows
effective as of the date hereof:

      1.    MODIFIED SECTION 2.2. Section 2.2 of the Purchase Agreement is
hereby amended to read as follows:

            2.2 ACCEPTANCE OF RECEIVABLES. Buyer shall have no obligation to
            purchase any receivable listed on an Invoice Transmittal. Buyer may
            exercise its sole discretion in approving the credit of each Account
            Debtor before buying any receivable. Upon acceptance by Buyer of all
            or any of the receivables described on any Invoice Transmittal,
            Buyer shall pay to Seller 80% percent of the face amount of each
            receivable Buyer desires to purchase, net of deferred revenue and
            offsets related to each specific Account Debtor; provided, however,
            such percentage shall be deemed to be 95% until the earlier of (i)
            July 31, 2004 or (ii) repayment of the Agility Obligations (as
            defined below). Such payment shall be the "Advance" with respect to
            such receivable. Buyer may, from time to time, in its sole
            discretion, change the percentage of the Advance. Upon Buyer's
            acceptance of the receivable and payment to Seller of the Advance,
            the receivable shall become a "Purchased Receivable." It shall be a
            condition to each Advance that (i) all of the representations and
            warranties set forth in Section 6 of this Agreement be true and
            correct on and as of the date of the related Invoice Transmittal and
            on and as of the date of such Advance

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            as though made at and as of each such date, and (ii) no Event of
            Default or any event or condition that with notice, lapse of time or
            otherwise would constitute an Event of Default shall have occurred
            and be continuing, or would result from such Advance.
            Notwithstanding the foregoing, in no event shall the aggregate
            amount of all Purchased Receivables outstanding at any time exceed
            FIVE MILLION DOLLARS ($5,000,000.00), provided, however, that until
            the repayment of the Agility Obligations such maximum amount shall
            be deemed to be TWO MILLION SIX HUNDRED THIRTY TWO THOUSAND DOLLARS
            ($2,632,000). As used herein, the term "Agility Obligations" shall
            mean any and all indebtedness and other obligations owing to Agility
            Capital LLC.

      2.    MODIFIED SECTION 3.2. Section 3.2 of the Purchase Agreement is
hereby amended to read as follows:

            3.2. FINANCE CHARGES. On each Reconciliation Date Seller shall pay
            to Buyer a finance charge in an amount equal to 2.50 percentage
            points above the Prime Rate per annum (BUT NO LESS THAN 6.75% PER
            ANNUM) multiplied by the gross average daily Account Balance
            outstanding during the applicable Reconciliation Period; provided,
            however, until the earlier of (i) July 31, 2004 and (ii) the
            satisfaction of the Agility Obligations, such finance charge shall
            be an amount equal to 5.125 percentage points above the Prime Rate
            per annum multiplied by the gross average daily Account Balance
            outstanding during the applicable Reconciliation Period (the
            "Finance Charges").

      3.    MODIFIED SECTION 6.2(g). Section 6.2(g) of the Purchase Agreement is
hereby amended to read as follows:

            (G)   Seller shall provide Buyer with a Compliance Certificate on a
            monthly basis to be received by Buyer no later than the 30th
            calendar day following each calendar month;

      4.    ASSIGNMENT OF CLAIMS. With respect to Purchased Receivables that are
owing from the United States or any department, agency or instrumentality
thereof (each a "Governmental Entity"), Seller covenants and agrees to comply
with the United States Assignment of Claims Act and within 30 days of the
purchase of any such receivable by Buyer, Buyer shall have received an executed
receipt of Notice of Assignment (or similar acknowledgment acceptable to Buyer)
from the applicable Governmental Entity. If Buyer does not receive an executed
receipt of Notice of Assignment (or similar acknowledgment acceptable to Buyer)
within such 30 day period, the same shall constitute a breach of Seller's
covenant above and such Purchased Receivable shall be subject to repurchase by
Seller in accordance with the terms of the Purchase Agreement.

      5.    ACKNOWLEDGMENT; AGREEMENT. Section 6.1(F) of the Purchase Agreement
states: "(F) Each Purchased Receivable shall be the property of the Buyer and
shall be collected by

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Buyer, but if for any reason it should be paid to Seller, Seller shall promptly
notify Buyer of such payment, shall hold any checks, drafts, or monies so
received in trust for the benefit of Buyer, and shall promptly transfer and
deliver the same to the Buyer; " Seller has informed Buyer that payments on
certain accounts receivable owing from Governmental Entities have, from time to
time, been delivered directly to Seller due to the payor's administrative
procedures. Buyer acknowledges the foregoing and agrees that any such
inadvertent delivery of payments to Seller shall not, in and of itself, result
in a breach of the Purchase Agreement, subject to Seller's compliance with all
the provisions in Section 6.1(F) as to any payments that Seller has received.
Moreover, Seller shall use its best efforts to cause all payments to be
delivered to Buyer and not to Seller, and the direct receipt of any payments by
Seller shall not be usual or customary nor shall it arise through any action or
omission of Seller.

      6.    LOCKBOX AGREEMENT. Seller has entered into a three party agreement
(the "Lockbox Agreement") with Buyer and a lockbox provider (the "Lockbox
Provider"), which Lockbox Agreement, or a replacement thereof acceptable to
Buyer, shall remain in effect during the term of the Purchase Agreement or
otherwise while any obligations remain outstanding thereunder. Seller shall use
the lockbox address as the payment address on all invoices issued by Seller and
shall direct all its Account Debtors to remit their payments to the lockbox
address. Upon Buyer's receipt of such collections, and provided that there does
not then exist an Event of Default or event that with notice, lapse or time or
otherwise would constitute an Event of Default, and subject to Buyer's rights in
the Collateral, Buyer agrees to remit promptly to Seller the amount of the
receivables collections it receives with respect to receivables other than
Purchased Receivables. It is understood and agreed by Seller that this Section
does not impose any affirmative duty on Buyer to do any act other than to turn
over such amounts. All such receivables and collections are Collateral and in
the event of Seller's default hereunder, Buyer shall have no duty to remit
collections of Collateral and may apply such collections to the obligations
hereunder and Buyer shall have the rights of a secured party under the
California Uniform Commercial Code.

      7.    WARRANTS. Within ten (10) days of the date of this Amendment, Seller
shall provide Buyer with seven (7)-year warrants to purchase 100,000 shares of
common stock of the Seller, at a price per share of $1.85, all on terms
acceptable to Buyer, as set forth in the Buyer's standard Warrant to Purchase
Stock and related documents with such changes thereto as are acceptable to Buyer
in its sole discretion. Said warrants shall be deemed fully earned on the date
hereof, shall be in addition to all interest and other fees, and shall be
non-refundable.

      8.    CONSENT; SUBORDINATION. Buyer hereby consents to Borrower entering
into and consummating the loan transaction with Creditor being entered into
substantially concurrently herewith for a principal amount of indebtedness of up
to $2,000,000, plus interest, fees and expenses, and which indebtedness is to be
secured by the personal property assets of the Borrower, subject, however, to
the Subordination Agreement (as defined below). In connection with the foregoing
loan transaction,, Seller shall cause Agility Capital LLC (the "Creditor") to
execute and deliver to Buyer a subordination agreement (the "Subordination
Agreement"), in form and substance satisfactory to Buyer in its sole discretion,
pursuant to which the Creditor shall subordinate any indebtedness owed to them
by the Seller and any lien which such Creditor may have, now or in the future,
against the assets of the Seller to the Obligations and to any

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security interest and/or lien in favor of Buyer. Seller shall cause the
Subordination Agreement to remain in full force and effect while any Obligations
remain outstanding and while the Purchase Agreement is in effect.

      9.    FEE. Seller shall pay to Buyer a fee of $10,000 in connection
herewith. Such fee is in addition to interest and to all other amounts payable
hereunder.

      10.   REPRESENTATIONS TRUE. Seller represents and warrants to Buyer that
all representations and warranties in the Purchase Agreement, as amended hereby,
are true and correct.

      11.   GENERAL PROVISIONS. This Amendment, the Purchase Agreement, any
prior written amendments to the Purchase Agreement signed by Buyer and the
Seller, and the other written documents and agreements between Buyer and the
Seller set forth in full all of the representations and agreements of the
parties with respect to the subject matter hereof and supersede all prior
discussions, representations, agreements and understandings between the parties
with respect to the subject hereof. Except as herein expressly amended, all of
the terms and provisions of the Purchase Agreement, and all other documents and
agreements between Buyer and the Seller shall continue in full force and effect
and the same are hereby ratified and confirmed. This Amendment may be executed
in any number of counterparts, which when taken together shall constitute one
and the same agreement.

      IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the date first above written.

SELLER:                                            BUYER:

SUPERCONDUCTOR                                     SILICON VALLEY BANK
TECHNOLOGIES INC.

BY_______________________________                 BY___________________________
    RESIDENT OR VICE PRESIDENT
                                                  TITLE________________________

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                         GUARANTOR CONSENT AND AGREEMENT

      The undersigned hereby consents to the foregoing Amendment and to the
documents and agreements referred to therein, and any termination thereof, and
to any and all other present documents and agreements between Buyer and Seller.
Nothing herein shall in any way limit any of the terms or provisions of the
Guaranty of the undersigned, all of which are hereby ratified and affirmed and
shall continue in full force and effect.

GUARANTOR:

CONDUCTUS, INC.

BY_______________________________
   PRESIDENT OR VICE PRESIDENT