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                        AMENDMENT TO EMPLOYMENT AGREEMENT

     This Amendment to Employment Agreement ("Amendment"), dated as of January
12, 2007, is entered into by and between Lightbridge, Inc., a Delaware
corporation (the "Company") and Robert E. Donahue of Northborough, Massachusetts
(the "Executive").

     WHEREAS, the Company and the Executive are parties to that certain
Employment Agreement, dated as of January 7, 2005 (the "Employment Agreement");

     WHEREAS, in accordance with Section 13(a) of the Employment Agreement, the
Company and the Executive wish to amend Sections 3(e) and 3(f) of the Employment
Agreement;

     NOW THEREFORE, in consideration of the mutual promises herein contained and
for other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the Company and the Executive hereby agree as follows:

     1.   The first sentence of Section 3(e) of the Employment Agreement is
hereby deleted in its entirety and the following substituted in its place and
stead:

          The other Stock Option (the "Second Stock Option") shall be for
          150,000 shares of Common Stock and such shares shall vest as follows:
          (i) in the event that the average closing price of Common Stock (as
          reported by the Nasdaq National Market) over any 20 consecutive
          trading day period beginning on or after the Effective Date and ending
          on or before the date the Executive's employment under this Agreement
          as President and Chief Executive Officer terminates (the "Average
          Closing Price") equals or exceeds $12.50, such Stock Option shall
          immediately vest as to 50,000 of such shares; (ii) in the event that
          the Average Closing Price during such period equals or exceeds $15.00,
          such Stock Option shall immediately vest as to an additional 50,000 of
          such shares; and (iii) in the event that the Average Closing Price
          during such period equals or exceeds $17.50, the Stock Option shall
          immediately vest in full.

     2.   The first sentence of Section 3(f) of the Employment Agreement is
hereby deleted in its entirety and the following substituted in its place and
stead:

          In the event that, within two (2) years following a Change of Control,
          either (i) the Company (or its successor) terminates the Executive's
          employment without Cause or (ii) the Executive terminates his
          employment for Good Reason (as defined below), then (A) any
          unexercised Company stock options then held by the Executive shall
          immediately vest in full and shall remain exercisable for 90 days
          following such termination, (B) subject to the Executive's execution
          of the Release and the Severance Agreement and to the provisions of
          Section 14 below, the Company shall pay the Executive in one lump sum
          payment an amount equal to 1.5 times his then-current Annual Base
          Salary plus 1.5 times the bonus earned by the Executive in respect of
          the immediately preceding calendar year (or, if the Company's
          Compensation Committee has not yet made a determination regarding


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          the amount of such bonus, 1.5 times 60% of the Executive's target
          bonus for such year), and (C) the Executive and his family members
          will be eligible to continue his group health insurance coverage in
          accordance with the federal COBRA law.

     3.   Capitalized terms used herein and without definition shall have their
respective meanings as set forth in the Employment Agreement.

     4.   The Company and the Executive hereby ratify and confirm that all of
the covenants, agreements, terms, conditions and other provisions of the
Employment Agreement are in full force and effect and unmodified, except as
altered by this Amendment.

     5.   This Amendment may be executed in one or more counterparts. A
facsimile or copy of a signature is valid as an original.



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     IN WITNESS WHEREOF, the Company and the Executive have executed this
Amendment as of the date first written above.



                                           LIGHTBRIDGE, INC.



                                           /s/ Kevin C. Melia
                                           ----------------------------------
                                           Kevin C. Melia
                                           Chairman of the Board of Directors



                                           /s/ Robert E. Donahue
                                           ----------------------------------
                                           Robert E. Donahue