STOCK OPTION AGREEMENT

THIS STOCK OPTION AGREEMENT (“ Agreement ”) is made and entered into by and between ZST Digital Networks, Inc. (“ Company ”), a Delaware corporation, and John Chen, M.D. (“ Optionee ”), effective on October 20, 2009.  (Company and Optionee are sometimes referred to herein as “ party ” or collectively as the “ parties .”)

WHEREAS, the Company has entered into an employment agreement dated as of October 8, 2009 for the purpose of retaining the services of the Optionee in the service of the Company (or any Parent or Subsidiary) (the “ Employment Agreement ”);

WHEREAS, Optionee is to render valuable services to the Company (or a Parent or Subsidiary), and this Agreement is executed pursuant to, and is intended to carry out the purposes of, the Employment Agreement in connection with the Company’s grant of an option to Optionee.  All capitalized terms in this Agreement shall have the meaning assigned to them in the attached Appendix.

NOW, THEREFORE, it is hereby agreed as follows:

1.            Grant of Option .  The Company hereby grants to Optionee, on October 20, 2009 (the “ Grant Date ”), an option to purchase up to Twenty-Five Thousand (25,000) shares of Common Stock (the “ Option Shares ”).  The Option Shares shall be purchasable from time to time during the option term specified in Paragraph 2 at $8.00 per share (the “ Exercise Price ”).

2.            Option Term .  This option shall have a term of five (5) years measured from the Grant Date (the “ Expiration Date ”) and shall accordingly expire at the close of business on the Expiration Date, unless sooner terminated in accordance with Paragraph 5.

3.            Limited Transferability .

(a)           This option shall be neither transferable nor assignable by Optionee other than by will or the laws of inheritance following Optionee’s death and may be exercised, during Optionee’s lifetime, only by Optionee.  However, Optionee may designate one or more persons as the beneficiary or beneficiaries of this option, and this option shall, in accordance with such designation, automatically be transferred to such beneficiary or beneficiaries upon the Optionee’s death while holding this option.  Such beneficiary or beneficiaries shall take the transferred option subject to all the terms and conditions of this Agreement, including (without limitation) the limited time period during which this option may, pursuant to Paragraph 5, be exercised following Optionee’s death.

(b)           As a Non-Statutory Option, this option may be assigned in whole or in part during Optionee’s lifetime to one or more members of Optionee’s family or to a trust established for the exclusive benefit of one or more such family members or to Optionee’s former spouse, to the extent such assignment is in connection with the Optionee’s estate plan or pursuant to a domestic relations order.  The assigned portion shall be exercisable only by the person or persons who acquire a proprietary interest in the option pursuant to such assignment.  The terms applicable to the assigned portion shall be the same as those in effect for this option immediately prior to such assignment.

4.            Dates of Exercise .  This option shall become immediately exercisable on the Grant Date, but to the extent exercised, will be subject to a repurchase right of the Company specified in Paragraph 10, which will lapse as follows: 50% of this option and Option Shares will vest six (6) months after the Grant Date and the remaining 50% will vest twelve (12) months after the Grant Date (the “ Vesting Schedule ”).

5.            Cessation of Service .  The option term specified in Paragraph 2 shall terminate (and this option shall cease to be outstanding) prior to the Expiration Date should any of the following provisions become applicable:

(a)           Should Optionee cease to remain in Service for any reason (other than Optionee’s termination of his employment without Good Reason or the Company’s termination of Optionee’s employment for Cause) while this option is outstanding, then Optionee (or any person or persons to whom this option is transferred pursuant to a permitted transfer under Paragraph 3) shall have a period of thirty (30) days (commencing with the date of such cessation of Service) during which to exercise this option, but in no event shall this option be exercisable at any time after the Expiration Date.

(b)           During the limited period of post-Service exercisability, this option may not be exercised in the aggregate for more than the number of Option Shares in which Optionee is, at the time of Optionee’s cessation of Service, vested pursuant to the Vesting Schedule or the special vesting acceleration provisions of Paragraph 6.  Upon the expiration of such limited exercise period or (if earlier) upon the Expiration Date, this option shall terminate and cease to be outstanding for any vested Option Shares for which the option has not been exercised.  To the extent Optionee is not vested in one or more Option Shares at the time of Optionee’s cessation of Service, this option shall immediately terminate and cease to be outstanding with respect to those shares.

(c)           Should Optionee’s Service be terminated by Optionee without Good Reason or by the Company for Cause, then this option shall terminate immediately and cease to remain outstanding.

6.            Accelerated Vesting .  In the event that Optionee’s Service is terminated by the Company for Cause or by Optionee for Good Reason, then the Option Shares at the time subject to this option but not otherwise vested shall automatically vest in full so that this option shall become exercisable for all of the Option Shares as fully vested shares and may be exercised for any or all of those Option Shares as vested shares pursuant to the terms of Section 5.

7.            Adjustment in Option Shares .  Should any change be made to the Common Stock by reason of any stock split, stock dividend, recapitalization, combination of shares, exchange of shares or other change affecting the outstanding Common Stock as a class without the Company’s receipt of consideration, appropriate adjustments shall be made to (i) the total number and/or class of securities subject to this option and (ii) the Exercise Price in order to reflect such change and thereby preclude a dilution or enlargement of benefits hereunder.

8.            Stockholder Rights .  The holder of this option shall not have any stockholder rights with respect to the Option Shares until such person shall have exercised the option, paid the Exercise Price and become the record holder of the purchased shares.

9.            Manner of Exercising Option .

(a)           In order to exercise this option with respect to all or any part of the Option Shares for which this option is at the time exercisable, Optionee (or any other person or persons exercising the option) must take the following actions:

(i)           Execute and deliver to the Company a Purchase Agreement for the Option Shares for which the option is exercised.

(ii)           Pay the aggregate Exercise Price for the purchased shares in cash or check made payable to the Company.

Should the Common Stock be registered under Section 12 of the 1934 Act at the time the option is exercised, then the Exercise Price may also be paid as follows:

(A)     &