PATENT PURCHASE AGREEMENT

Exhibit 10.21

PATENT PURCHASE AGREEMENT

This PATENT PURCHASE AGREEMENT (“Agreement”) is entered into on April 6, 2005 (“ Effective Date ”) by and between Faust Communications, LLC, with an office at [***] (“ Purchaser ”), and NeoMagic Corporation with an office at 3250 Jay Street, Santa Clara, CA 95054 (“ Seller ”). The parties hereby agree as follows.

1. B ACKGROUND

1.1 Seller owns certain United States Letters Patents and/or applications for United States Letters Patents and/or related foreign patents and applications.

1.2 Seller wishes to sell its right, title and interest in such patents and applications to Purchaser.

1.3 Purchaser wishes to purchase such patents and applications.

2. D EFINITIONS

2.1 “ Assignment Agreements ” means the agreements assigning ownership of the Patents from the inventors and/or prior owners to Seller.

2.2 “Closing Date” means the date on which Purchaser has paid the Seller the total Purchase Price.

2.3 “ List of Prosecution Counsel ” means the names and addresses of prosecution counsel who prosecuted the Patents and who are currently handling the Patents.

2.4 “ Patents ” means those patents and applications listed in Exhibit A hereto, and all reissues, reexaminations, extensions, continuations, continuations in part, continuing prosecution applications, and divisions of such patents and applications; provisional patent applications that are or will be continuations or continuations in part of such patents and applications; and foreign counterparts to any of the foregoing including without limitation utility models.

2.5 “ Purchase Price ” means Four Million Five Hundred and Fifty Thousand Dollars (USD 4,550,000).

3. D ELIVERY AND P AYMENT

3.1 Delivery . On the Effective Date, Seller shall deliver an executed original of the Assignment of Patent Rights in Exhibit B hereto to Purchaser.

3.2 Payment . On the Effective Date, Purchaser shall pay to Seller the Purchase Price.

4. T RANSFER OF P ATENTS

4.1 Patent Assignment . Effective on the Closing Date, Seller hereby sells, assigns, transfers and conveys to Purchaser all right, title and interest it has in and to the Patents and all inventions and discoveries described therein, including without limitation, all rights of Seller under the Assignment Agreements, and all rights of Seller to collect royalties under such Patents.

4.2 Assignment of Causes of Action . Effective on the Closing Date, Seller hereby sells, assigns, transfers and conveys to Purchaser all right, title and interest it has in and to all causes of action and enforcement rights, whether currently pending, filed, or otherwise, for the Patents and all inventions and discoveries described therein, including without limitation all rights to pursue damages, injunctive relief and other remedies for past, current and future infringement of the Patents.

4.3 Grant Under Patent Rights . Effective on the Closing Date, Purchaser hereby grants to Seller, under the Patent Rights (as defined in Exhibit B hereto), and for the lives thereof, a royalty-free, irrevocable, non-exclusive, non-transferable (except as permitted under Section 4.3 below), worldwide right and license (the “ Seller License ”) to practice the methods and to make, have made, use, distribute, lease, sell, offer for sale, import, export, develop and otherwise dispose of and exploit any products, processes or services covered by the Patent Rights (“ Covered Products ”). This Seller License shall also apply to the reproduction and subsequent distribution of Covered Products, in substantially identical form as they are distributed by the Seller, by authorized agents of the Seller such as a distributor, replicator, VAR or OEM.

4.4 Limitation on Transferability. The Seller License in Section 4.3 above may be transferred one time to a purchaser of all, or substantially all, of Seller’s operating assets (other than cash) which are covered by the Seller License, or to a party that by merger or otherwise, acquires all, or substantially all, of Seller’s outstanding capital stock (any such transaction referred to as the “ Acquisition ” and any such purchaser or acquiring party referred to as the “ Assignee ”). In the event of such Acquisition, the Seller License shall automatically become limited to the Covered Products of (1) Seller that are either under development or that are commercially released on the effective date of such Acquisition and (2) Assignee that are commercially released as of the effective date of the Acquisition and, for each of (1) and (2) any new versions that have merely incremental differences from Seller’s and Assignee’s Covered Products covered by the Seller License on the effective date of the Acquisition (all such products, processes and services referred to collectively as the “ Covered Items ”). In no event, however, shall the Seller License be construed or interpreted to include any other products, processes or services of the Seller, Assignee or any other third party. The Seller License with respect to the Covered Items shall automatically terminate upon any subsequent Acquisition by any third party (“ Subsequent Acquisition ”), provided that the Seller License shall continue in full force and effect with respect to any commercially

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released Covered Items of Seller or Assignee that are in inventory or are in production on the effective date of any Subsequent Acquisition. Seller or Assignee shall provide Purchaser written notice within one hundred and twenty (120) days of the Seller License being transferred under this Section 4.4 and specifically detail the Covered Items as of the effective date of the Acquisition. If Purchaser is not so notified of such transfer of the Seller License within one hundred and twenty (120) days of the effective date of Acquisition, the Seller License under Section 4.3 shall automatically terminate.

5. A DDITIONAL O BLIGATIONS

5.1 Further Assurances . At the reasonable request of Purchaser and without demanding further consideration from Purchaser, Seller agrees to execute and deliver such other instruments and do and perform such other acts and things as may be reasonably necessary for effecting completely the consummation of the transfer of ownership in and to the Patents as contemplated hereby, including without limitation execution, acknowledgment and recordation of other such papers, and using all reasonable best efforts to obtain the same from the respective inventors, as necessary or desirable for fully perfecting and conveying unto Purchaser the benefit of the transfer of ownership in and to the Patents as contemplated hereby.

5.2 Further Assistance . Subject to the terms and conditions hereof, Seller agrees, upon the reasonable request of Purchaser, to do all things necessary, proper, or advisable, including without limitation the execution, acknowledgment and recordation of specific assignments, oaths, declarations and other documents on a country-by-country basis, to assist Purchaser in obtaining, perfecting, sustaining, and/or enforcing the Patent Rights. Such assistance may also include providing, and obtaining from the respective inventors, prompt production of pertinent facts and documents, giving of testimony, execution of petitions, oaths, powers of attorney, specifications, declarations or other papers and other assistance reasonably necessary for filing patent applications, complying with any duty of disclosure, and conducting prosecution, reexamination, reissue, interference or other priority proceedings, opposition proceedings, cancellation proceedings, public use proceedings, infringement or other court actions and the like with respect to the Patent Rights. Seller’s agreement to render any of the foregoing assistance is subject to Purchaser’s payment of all reasonable expenses of Seller incurred in connection therewith and the availability of Seller’s personnel.

5.3 Payment of Fees . Seller shall pay any maintenance fees, annuities, and the like due on the Patents for a period of thirty (30) calendar days following the Effective Date.

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6. R EPRESENTATIONS AND W ARRANTIES

Seller hereby warrants to Purchaser as follows:

6.1 Authority . Seller has the right and authority to enter into this Agreement and to carry out its obligations hereunder.

6.2 Title and Contest . Seller has good and marketable title to the Patents, including without limitation all rights, title, and interest in the Patents to sue for infringement thereof. The Patents are free and clear of all liens, mortgages, security interests or other encumbrances, and restrictions on transfer. There are no actions, suits, claims or proceedings threatened, pending or in progress on the part of any named inventor of the Patents relating in any way to the Patents and Seller has not received notice of (and Seller is not aware of any facts or circumstances which could reasonably be expected to give rise to) any other actions, suits, investigations, claims or proceedings threatened, pending or in progress relating in any way to the Patents. There are no existing contracts, agreements, options, commitments, proposals, bids, offers, or rights with, to, or in any person to acquire any of the Patents.

6.3 Existing Licenses . No rights or licenses have been granted under the Patents.

6.4 Restrictions on Rights . Purchaser will not be subject to any covenant not to sue or similar restrictions on its enforcement or enjoyment of the Patents as a result of the transaction contemplated in this Agreement, or any prior transaction related to the Patents.

6.5 Conduct . To Seller’s knowledge, none of Seller or its representatives has engaged in any conduct, or omitted to perform any necessary act, the result of which would invalidate any of the Patents or hinder their enforcement, including but not limited to misrepresenting Seller’s patent rights to a standard-setting organization.

6.6 Enforcement . Seller has not put a third party on notice of actual or potential infringement of any of the Patents or considered enforcement action(s) with respect to any of the Patents.

6.7 Patent Office Proceedings . None of the Patents have been or are currently involved in any reexamination, reissue, interference proceeding, or any similar proceeding and that no such proceedings are pending or threatened.

6.8 Related Assets. There are no other patents issued and/or applications pending for or on behalf of Seller which are subject to a Terminal Disclaimer under 37 C.F.R. §1.321 that require any of such patents issued and/or applications and any of the Patents conveyed in this Agreement to remain under common ownership.

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6.10 Validity and Enforceability . To Seller’s knowledge, the Patents have never been found invalid or unenforceable for any reason in any administrative, arbitration, judicial or other proceeding, and Seller has not received any notice or information of any kind from any source suggesting that the Patents may be invalid or unenforceable.

7. M ISCELLANEOUS

7.1 No Representation or Warranty . SELLER MAKES NO REPRESENTATIONS OR WARRANTIES WHATSOEVER THAT ANY OF THE PATENTS COVERED BY THIS AGREEMENT ARE EITHER VALID OR ARE INFRINGED BY ANY OTHER PARTIES.

7.2 Limitation on Consequential Damages. EXCEPT IN THE CASE OF FRAUD BY SELLER, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR LOSS OF PROFITS, OR ANY OTHER INDIRECT OR SPECIAL, CONSEQUENTIAL, PUNITIVE OR INCIDENTAL DAMAGES, HOWEVER CAUSED, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. THE PARTIES ACKNOWLEDGE THAT THESE LIMITATIONS ON POTENTIAL LIABILITIES WERE AN ESSENTIAL ELEMENT IN SETTING CONSIDERATION UNDER THIS AGREEMENT

7.3 Limitation of Liability . EXCEPT IN THE CASE OF FRAUD BY SELLER, IN NO EVENT SHALL EITHER PARTY’S TOTAL LIABILITY UNDER THIS AGREEMENT EXCEED THE PURCHASE PRICE. THE PARTIES ACKNOWLEDGE THAT THESE LIMITATIONS ON POTENTIAL LIABILITIES WERE AN ESSENTIAL ELEMENT IN SETTING CONSIDERATION UNDER THIS AGREEMENT.

7.4 Compliance with Laws . Notwithstanding anything contained in this Agreement to the contrary, the obligations of the parties shall be subject to all laws, present and future, of any government having jurisdiction over the parties and this transaction, and to orders, regulations, directions or requests of any such government.

7.5 Confidentiality of Terms . The parties hereto shall keep the terms and existence of this Agreement and the identities of the parties hereto confidential and shall not now or hereafter divulge any of this information to any third party except: (a) with the prior written consent of the other party, such consent shall not be unreasonably withheld; (b) as otherwise may be required by law or legal process, including in confidence to financial advisors in their capacity of advising a party in such matters; (c) during the course of litigation, so long as the disclosure of such terms and conditions are restricted in the same manner as is the confidential information of other litigating parties; or (d) in confidence to its legal counsel, accountants, banks and financing sources and their advisors solely in connection with complying with financial transactions; provided that, in (b) through (d) above, (i) the disclosing party shall use all legitimate and legal means available to minimize the disclosure to third parties, including without limitation seeking a confidential treatment request or protective order whenever appropriate or available; and (ii), other than disclosures

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pursuant to subsection (d) above, the disclosing party shall provide the other party with at least ten (10) days prior written notice of such disclosure. The above notwithstanding, Purchaser agrees that, on or after the Effective Date, Seller shall be allowed to make one or more public announcements in order to fulfill its requirements as a public company with respect to the disclosure of this Agreement. Seller agrees that it will submit any such announcements to Purchaser at least two (2) days prior to its making those announcements for Purchaser’s approval, which approval shall not be unreasonably withheld.

7.6 Governing Law . Any claim arising under or relating to this Agreement shall be governed by the internal substantive laws of the State of New York without regard to principles of conflict of laws.

7.7 Jurisdiction . Each party hereby agrees to jurisdiction and venue in the courts of the State of New York or the Federal courts sitting therein for all disputes and litigation arising under or relating to this Agreement.

7.8 Entire Agreement . The terms and conditions of this Agreement, including its exhibits, constitutes the entire agreement between the parties with respect to the subject matter hereof, and merges and supersedes all prior and contemporaneous agreements, understandings, negotiations and discussions. Neither of the parties shall be bound by any conditions, definitions, warranties, understandings, or representations with respect to the subject matter hereof other than as expressly provided herein. The section headings contained in this Agreement are for reference purposes only and shall not affect in any way the meaning or interpretation of this Agreement. No oral explanation or oral information by either party hereto shall alter the meaning or interpretation of this Agreement. No amendments or modifications shall be effective unless in a writing signed by authorized representatives of both parties. These terms and conditions will prevail notwithstanding any different, conflicting or additional terms and conditions which may appear on any purchase order, acknowledgment or other writing not expressly incorporated into this Agreement. This Agreement may be executed in two (2) or more counterparts, all of which, taken together, shall be regarded as one and the same instrument. The following exhibits are attached hereto and incorporated herein: Exhibit A (entitled “Patent Rights to be Assigned”) and Exhibit B (entitled “Assignment of Patent Rights”).

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7.9 Notices: All no