(a)

Executive acknowledges the grant of a stock option (the "Option") covering 90,000 shares of common stock under the Company's 2013 Equity Incentive Plan ("Plan") as of the Start Date. The Option is designated as an incentive stock option, subject to applicable limitations imposed under the Internal Revenue Code of 1986, as amended (the "Code").  The Exercise Price of the Option is equal to the Fair Market Value as of the Date of Grant.  The Option will vest and become exercisable as follows:

(i)

no part of the option may be exercised prior to the date six months after the Date of Grant or at any time after the Date of Expiration;

(ii)

beginning on the date six months after the Date of Grant, the Option may be exercised as to a maximum of 12.5% of the Covered Shares; and

(iii)

beginning on each date three months thereafter, the Option may be exercised as to an additional 6.25% of the Covered Shares until the Option is exercisable as to all of the Covered Shares such that the Option is fully vested on the fourth anniversary of the Date of Grant.

(b)

Executive acknowledges the grant of 22,500 Restricted Stock Units (RSUs) under the Plan as of the Start Date.  The RSUs shall vest in cumulative installments as follows:

(i)

first, with respect to twelve and one-half percent (12.5%) of the RSUs, on the date six (6) months after the Date of Grant;

(ii)

second, with respect to an additional twelve and one-half percent (12.5%) of the RSUs, on the date twelve (12) months after the Date of Grant;

(iii)

 thereafter, in equal increments of twenty-five percent (25%) of the RSUs on an annual basis beginning on the second anniversary of the Date of Grant such that the RSUs are fully vested on the fourth anniversary of the Date of Grant.

(a)

For purposes of this Agreement, "Accrued Obligations" means: (i) Executive's earned and unpaid Base Salary through the Termination Date; (ii) reimbursement for any reimbursable business expenses incurred by Executive through the Termination Date in accordance with Section 4.05; and (iii) Executive's accrued but unused vacation time as of the Termination Date.  The amounts payable hereunder shall be paid no later than sixty (60) days following Executive's Termination Date.

(b)

For purposes of this Agreement, "Termination Date" means: the effective date of Executive's "separation from service" as defined in Section 409A of the Code.

(i)

a material adverse change in Executive's functions, duties, or responsibilities as Senior Vice President and General Counsel with the Company which change would cause Executive's position to become one of materially lesser responsibility, importance, or scope;

(ii)

a material change in the geographic location at which Executive must perform services to the Company of 50 miles or more from the Company's headquarters in Rockville, Maryland (unless Executive is permitted to telecommute rather than work at the Company's new headquarters); or

(iii)

a material breach of this Agreement by the Company.

(a)

The payment to Executive of the Severance Amount in substantially equal installments over one year (with the first payment commencing on the first payroll date that occurs at least 28 days following the Termination Date), in accordance with Employer's normal payroll practices ("Severance Period").  Severance Amount means (i) one year of Executive's Base Salary and, except as set forth in the next sentence, (ii) the applicable percentage of the maximum Target Bonus (as defined in Section 4.02 of this Agreement).  Notwithstanding the foregoing, Executive's entitlement to receive the Target Bonus pursuant to this Section 5.05(a) shall be phased-in with annual, cumulative 25% increments beginning on the first anniversary of the date of this Agreement.  For the avoidance of doubt and by way of example and not of limitation, if Executive is terminated by Employer without Cause or by Executive for Good Reason prior to the first anniversary of this Agreement, Executive's Severance Amount shall not include any portion of the Target Bonus.  Thereafter, on each of the first, second, third, and fourth anniversaries of the date of  this Agreement, the Severance Amount shall be increased by 25%, 50%, 75% and 100%, respectively, of the Target Bonus.  For the avoidance of doubt and by way of example and not of limitation, if Executive is terminated by Employer without Cause or by Executive for Good Reason after the first anniversary of this Agreement but prior to the second anniversary of this Agreement, Executive's Severance Amount would include 25% of the maximum Target Bonus (35% of Executive's Base Salary).

(b)

The continuation of Executive's participation in the Company's medical, dental, and vision benefit plans at the same premium cost to Executive as charged to Executive immediately prior to the Termination Date for a period of twelve (12) months immediately following the Termination Date, or if earlier, until Executive obtains other employment which provides the same type of benefit; provided, however, that (a) it is understood and agreed that such continued medical, dental and vision benefits may at the election of the Company be provided by Executive electing the continuation of such coverage pursuant to COBRA with the Company reimbursing Executive for COBRA premiums to the extent required so that Executive's premium cost for the coverage in effect for Executive prior to the Termination Date is substantially the same as immediately prior to the Termination Date, and (b) if the Company determines, in its reasonable judgment, that providing medical, dental, and/or vision benefits in accordance with the preceding provisions of this Section 5.05(b) would result in a violation of applicable law, the imposition of any penalties under applicable law, or adverse tax consequences for participants covered by the Company's medical, dental, and/or vision plans, the Company may terminate such coverage (or reimbursement) with respect to Executive and instead pay to Executive taxable cash payments at the same time and in the same amounts as the Company would have paid as premiums (or as COBRA premium reimbursements) to provide such coverage. 

(c)

If the Termination Date occurs upon or within one year after the occurrence of a Change in Control, each stock option and RSU award granted by the Company to Executive that is outstanding as of the Termination Date and is not fully vested as of the date of the Termination Date shall, as of the date Executive provides the Company with the Irrevocable Release provided for in Section 5.06 (but only if the Irrevocable Release is provided within the 60 day period provided for by Section 5.06), become vested with respect to 50% (only) of the shares with respect to which the stock option or RSU award is not vested as of the Termination Date; provided, however that in no event shall any such option vest to the extent the option has expired prior to the date Executive provides the Company with the Irrevocable Release.  For the avoidance of doubt, in the event that any of Executive's unvested stock options or unvested RSUs are to be terminated in connection with a Change of Control, Executive shall nonetheless be entitled to the accelerated vesting described in and subject to the conditions of this clause (c).

(i)

For purposes of this Agreement, "Change of Control" means: "Change of Control" means, and shall be deemed to have occurred, if:

a.

any Person, excluding (i) employee benefit plans of the Company or any of its Affiliates, is or becomes the "beneficial owner" (as defined in Rules 13d-3 and 13d-5 under the Exchange Act, which Rules shall apply for purposes of this clause (a) whether or not the Company is subject to the Exchange Act), directly or indirectly, of Company securities representing more than fifty percent (50%) of the combined voting power of the Company's then outstanding securities ("Voting Power");

b.

the Company consummates a merger, consolidation, share exchange, division or other reorganization or transaction of the Company (a "Fundamental Transaction") with any other corporation, other than a Fundamental Transaction that results in the voting securities of the Company outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity) at least fifty percent (50%) of the combined Voting Power immediately after such Fundamental Transaction of (i) the Company's outstanding securities, (ii) the surviving entity's outstanding securities, or (iii) in the case of a division, the outstanding securities of each entity resulting from the division;

c.

the stockholders of the Company approve a plan of complete liquidation or winding‑up of the Company or the consummation of the sale or disposition (in one transaction or a series of transactions) of all or substantially all of the Company's assets; or

d.

during any period of 24 consecutive months, individuals who at the beginning of such period constituted the Board (including for this purpose any new director whose election or nomination for election by the Company's stockholders was approved by a vote of at least two-thirds (2/3) of the directors then still in office who were directors at the beginning of such period or whose appointment, election or nomination was previously so approved or recommended) cease for any reason to constitute at least a majority of the Board.

(a)

During Executive's employment with Company and for a period of 12 months following termination of employment for any reason (the "Non-Competition Period"), Executive shall not either directly or indirectly, on Executive's own or another's behalf, engage in or assist others in any of the following activities (except on behalf of Company):

(i)

(whether as principal, agent, partner or otherwise) engage in, own, manage, operate, control, finance, invest in, participate in, or otherwise carry on, or be employed by, associated with, or in any manner connected with, lend such Executive's name to, lend Executive's credit to, or render services or advice to a Competing Business anywhere in the Geographic Area;

(ii)

provide or develop any products, technology or services that are the same or Substantially Similar to the products, technology and services provided or developed by the Company or any of its Affiliates;

(iii)

induce or attempt to induce any customer, agent, supplier, licensee, or business relation of the Company or any of its Affiliates to cease doing business with the Company or any of its Affiliates, or in any way interfere with the relationship between any customer, supplier, licensee, or business relation of the Company or any of its Affiliates; or

(iv)

on behalf of a Competing Business, solicit or attempt to solicit the business or patronage of any Person who is a customer or agent of the Company or any of its Affiliates, whether or not Executive had personal contact with such Person.

(b)

During Executive's employment with Company and for a period of 12 months following termination of employment for any reason  (the "Non-Solicitation Period"), Executive shall not either directly or indirectly, on Executive's own or another's behalf, engage in or assist others in any of the following activities:

(i)

solicit, encourage, or take any other action which is intended to induce any employee, independent contractor or agent of the Company or any of its Affiliates to terminate Executive's employment or other business relationship with the Company or such Affiliate;

(ii)

in any way interfere in any manner with the employment or other business relationship between the Company and/or any of its Affiliates, on the one hand, and any employee, independent contractor or agent of the Company or such Affiliate, on the other hand; or

(iii)

employ, or otherwise engage as an employee, independent contractor or otherwise, any individual who was an employee or was otherwise affiliated with the Company or any of its Affiliates from the period beginning one year prior to Executive's last day of employment and continuing through the expiration of the Non-Solicitation Period.

(a)

"Affiliate" means, with respect to any Entity, any Entity that, directly or indirectly through one or more intermediaries, controls, is controlled by or under common control with, such Entity.

(b)

"Agreement" means this Employment Agreement.

(c)

"Company Business" means the research, development, testing and/or marketing/sales of pharmaceutical products or processes that are, rely on, target or rely upon (a) CD3 (when targeted individually), (b) HER2, (c) B7-H3, (d) CD123, (e) gpA33, (f) CD32b and CD79b (when jointly targeted), (g)  any other undisclosed target (pre-clinical or clinical) either being actively developed by Employer or the subject of a collaboration between Employer and a third party, or (h) any effort to develop diabodies similar to the Company's "DART" technology including DART conjugates.

(d)

"Company Property" means all physical materials, documents, information, keys, computer software and hardware, including laptop computers and mobile or handheld scheduling computers, manuals, data bases, product samples, tapes, magnetic media, technical notes and any other equipment or items which Company provides for or to Executive or which otherwise belongs to the Company, and those documents and items which Executive may develop or help develop while in Company's employ, whether or not developed during regular working hours or on Company's premises.  The term "Company Property" shall include the original of such materials, any copies thereof, any notes derived from such materials, and any derivative work of such materials.

(e)

"Competing Business" means any other Entity engaged in the Company Business, other than the Company and its Affiliates.

(f)

"Confidential Information" means the trade secrets and other information of Company, including but not limited to (i) the customer lists, customer contact information, customer purchase information, pricing information, strategic and marketing plans, compilations of customer information, names of employees, contracts with third parties, training, financial and marketing books, sales projections, internal employer databases, reports, manuals and information including information related to Company, its Affiliates or its customers, including those documents and items which any employee may develop or help develop while in the employ of the Company or any of its Affiliates, whether or not developed during regular working hours or on the premises of the Company or such Affiliate; (ii)  the identity, skills, personnel file information, performance appraisals and compensation of job applicants, employees, contractors, and consultants; (iii) specialized training; (iv) source code, scripts, user screens, reports or any other information pertaining to the internal information technology or network of the Company and/or its Affiliates, including the proprietary database system commonly referred to as the Office System; and (v) information related to inventions owned by the Company or any of its Affiliates or licensed from third parties; and unless the context requires otherwise, the term "Confidential Information" includes the original of such materials, any copies thereof, any notes derived from such materials, and any derivative work of such materials.  The term "Confidential Information" does not include (1) information that was or becomes generally available publicly other than through disclosure by Executive, or (2) is required to be disclosed to any governmental agency or self-regulatory body or is otherwise required to be disclosed by law.  Unless the context requires otherwise, the term "Confidential Information" shall include the original of such materials, any copies thereof, any notes derived from such materials, and any derivative work of such materials.

(g)

"Entity" means and includes any person, partnership, association, corporation, limited liability company, trust, unincorporated organization or any other business entity or enterprise.

(h)

"Geographic Area" mean those states in which the Company or any of its subsidiaries conducts business or in which its products are being sold or marketed at the time of the termination of Executive's employment.

(i)

"Goodwill" means the value of the relationships between the Company and its agents, customers, vendors, labs, and employees.

(j)

"Substantially Similar" means substantially similar in function or capability or otherwise competitive to the products or services being developed, manufactured or sold by the Company during and/or at the end of Executive's employment, or are marketed to substantially the same type of user or customer as that to which the products and services of the Company are marketed or proposed to be marketed.

(a)

the restrictions are ancillary to an otherwise enforceable agreement including the provisions of this Agreement regarding the disclosure, ownership and use of the Confidential Information and Goodwill of Company;

(b)

the limitations as to time, geographical area, and scope of activity to be restricted are reasonable and acceptable to Executive, and do not impose any greater restraint than is reasonably necessary to protect the Goodwill and other legitimate business interests of Company;

(c)

the performance by Executive, and the enforcement by Company, of such promises and covenants will cause no undue hardship on Executive;

(d)

Executive will play a key business role for the Company in which he will have access to the Company's Confidential Information and Goodwill;

(e)

the time periods covered by the promises and covenants will not include any period(s) of violation of, or any period(s) of time required for litigation brought by Company to enforce any such promise or covenant, it being understood that the extension of time provided in this paragraph may not exceed two (2) years.

(a)

This Agreement is made under and shall be governed by and construed in accordance with the laws of Maryland, without regard to its conflicts of law principles.

(b)

With respect to claims by the Company against Executive related to Executive's threatened or actual breach of Section 6 of this Agreement, each Party hereby irrevocably agrees that all actions or proceedings concerning such disputes may be brought by the Company in (a) the United States District Court for the District of Maryland; or (b) in any court of the State of Maryland sitting in Montgomery County, provided that the United States District Court lacks subject matter jurisdiction over such action or proceeding.  Executive consents to jurisdiction of and venue in the courts in the State of Maryland set forth in this Section, and hereby waives to the maximum extent permitted by applicable law any objection which Executive may have based on improper venue or forum non conveniens.

(c)

Except to the extent provided for in subsection (b) above,  the Company and Executive agree that any claim, dispute or controversy arising under or in connection with this Agreement, or otherwise in connection with Executive's employment by the Company or termination of his employment (including, without limitation, any such claim, dispute or controversy arising under any federal, state or local statute, regulation or ordinance or any of the Company's employee benefit plans, policies or programs) shall be resolved solely and exclusively by binding, confidential, arbitration.  The arbitration shall be held in Rockville, MD (or at such other location as shall be mutually agreed by the parties).  The arbitration shall be conducted in accordance with the Commercial Rules of the American Arbitration Association (the "AAA") in effect at the time of the arbitration, including the Expedited Procedures.  All fees and expenses of the arbitration, including a transcript if either requests, shall be borne equally by the parties.  Each party is responsible for the fees and expenses of its own attorneys, experts, witnesses, and preparation and presentation of proofs and post-hearing briefs (unless the party prevails on a claim for which attorney's fees are recoverable under law).  In rendering a decision, the arbitrator shall apply all legal principles and standards that would govern if the dispute were being heard in court.  This includes the availability of all remedies that the parties could obtain in court.  In addition, all statutes of limitation and defenses that would be applicable in court, will apply to the arbitration proceeding.  The decision of the arbitrator shall be set forth in writing, and be binding and conclusive on all parties.  Any action to enforce or vacate the arbitrator's award shall be governed by the Federal Arbitration Act, if applicable, and otherwise by applicable state law.  If either the Company or Executive improperly pursues any claim, dispute or controversy against the other in a proceeding other than the arbitration provided for herein, the responding party shall be entitled to dismissal or injunctive relief regarding such action and recovery of all costs, losses and attorney's fees related to such action.