Exhibit 10.25

ADDENDUM

TO

STOCK OPTION AGREEMENT

The following provisions are hereby incorporated into, and are hereby made a
part of, that certain Stock Option Agreement (the “Option Agreement”) by and
between Immunomedics, Inc. (the “Corporation”) and
                                         (“Optionee”) evidencing the stock
option (the “Option”) granted this day to Optionee under the terms of the
Corporation’s 2006 Stock Incentive Plan, and such provisions are effective
immediately. All capitalized terms in this Addendum, to the extent not otherwise
defined herein, shall have the meanings assigned to them in the Option
Agreement.

INVOLUNTARY TERMINATION FOLLOWING

CHANGE IN CONTROL/HOSTILE TAKE-OVER

1. To the extent the Option is to be assumed in connection with a Change in
Control or otherwise continued in effect, the Option shall not, pursuant to the
provisions of Paragraph 6 of the Option Agreement, accelerate upon the
occurrence of that Change in Control, and the Option (as so assumed or
continued) shall accordingly continue, over Optionee’s period of Service after
the Change in Control, to become exercisable for the Option Shares in one or
more installments in accordance with the provisions of the Option Agreement.
However, immediately upon an Involuntary Termination of Optionee’s Service
within twelve (12) months following such Change in Control, the Option (as so
assumed or continued) shall, to the extent outstanding at the time but not
otherwise fully exercisable, automatically accelerate so that such Option shall
become immediately exercisable for all the Option Shares at the time subject to
the Option and may be exercised for any or all of those Option Shares as fully
vested shares.

2. The Option shall not accelerate upon the occurrence of a Hostile Take-Over,
and any successor entity in the Hostile Take-Over shall assume or otherwise
continue in effect such Option. The Option (as so assumed or continued) shall,
over Optionee’s period of Service following such Hostile Take-Over, continue to
become exercisable for the Option Shares in one or more installments in
accordance with the provisions of the Option Agreement. However, immediately
upon an Involuntary Termination of Optionee’s Service within twelve (12) months
following the Hostile Take-Over, the Option (as so assumed or continued) shall,
to the extent outstanding at the time but not otherwise fully exercisable,
automatically accelerate so that the Option shall become immediately exercisable
for all the Option Shares at the time subject to the Option and may be exercised
for any or all of those Option Shares as fully vested shares.

3. The Option as accelerated pursuant to this Addendum shall remain so
exercisable until the earlier of (i) the Expiration Date or (ii) the expiration
of the one (1)-year period measured from the date of the Optionee’s Involuntary
Termination.

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4. Should the Option be replaced with a cash retention plan in accordance with
Paragraph 6(a) of the Option Agreement, then the balance credited to the
Optionee under that plan at the time of his or her Involuntary Termination shall
immediately be paid to the Optionee in a lump sum upon such Involuntary
Termination, subject to the Corporation’s collection of all applicable
withholding taxes; provided, however, that Optionee shall be entitled to such
payment only if the Optionee’s Involuntary Termination occurs within twelve
(12) months following the Change in Control or Hostile Take-Over to which the
cash retention plan pertains.

5. For purposes of this Addendum the following definitions shall be in effect:

(i) An Involuntary Termination shall mean the termination of Optionee’s Service
by reason of:

(A) Optionee’s involuntary dismissal or discharge by the Corporation (or any
Parent or Subsidiary) for reasons other than Misconduct, or

(B) Optionee’s voluntary resignation following (A) a change in Optionee’s
position with the Corporation (or Parent or Subsidiary employing Optionee) which
materially reduces Optionee’s duties and responsibilities or the level of
management to which Optionee reports, (B) a reduction in Optionee’s level of
compensation (including base salary, fringe benefits and target bonus under any
corporate performance based bonus or incentive programs) by more than fifteen
percent (15%) or (C) a relocation of Optionee’s place of employment by more than
fifty (50) miles, provided and only if such change, reduction or relocation is
effected by the Corporation without Optionee’s consent.

(ii) A Hostile Take-Over shall be deemed to occur in the event of a change in
ownership or control of the Corporation effected through either of the following
transactions:

(A) a change in the composition of the Board over a period of thirty-six
(36) consecutive months or less such that a majority of the Board members
ceases, by reason of one or more contested elections for Board membership, to be
comprised of individuals who either (i) have been Board members continuously
since the beginning of such period or (ii) have been elected or nominated for
election as Board members during such period by at least a majority of the Board
members described in clause (i) who were still in office at the time the Board
approved such election or nomination, or

(B) the acquisition, directly or indirectly, by any person or related group of
persons (other than the Corporation or a person that directly or indirectly
controls, is controlled by, or is under common control with, the Corporation) of
beneficial ownership (within the meaning of Rule 13d-3 of the Securities
Exchange Act of 1934, as amended) of securities possessing more than

 

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fifty percent (50%) of the total combined voting power of the Corporation’s
outstanding securities pursuant to a tender or exchange offer made directly to
the Corporation’s shareholders which the Board does not recommend such
shareholders to accept.

6. The provisions of Paragraph 3 of this Addendum shall govern the period for
which the Option is to remain exercisable following the Involuntary Termination
of Optionee’s Service within twelve (12) months after the Change in Control or
Hostile Take-Over and shall supersede any provisions to the contrary in
Paragraph 5 of the Option Agreement.

IN WITNESS WHEREOF, Immunomedics, Inc. has caused this Addendum to be executed
by its duly authorized officer as of the Effective Date specified below.

 

IMMUNOMEDICS, INC. By:  

 

Title:  

 

 

EFFECTIVE DATE:  

 

 

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