EXHIBIT 99.2

                                  [PROXY CARD]

                          CORSAIR COMMUNICATIONS, INC.

           THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS

                         SPECIAL MEETING OF STOCKHOLDERS

                                  [DATE], 2001

         The undersigned stockholder of Corsair Communications, Inc. (the
"Company") hereby appoints Thomas C. Meyer and Martin J. Silver and each or any
of them, proxies, with full power of substitution to each and to each substitute
appointed pursuant to such power, of the undersigned to vote all shares of
common stock of the Company that the undersigned may be entitled to vote at the
Special Meeting of Stockholders of the Company to be held on [DATE], 2001, and
at any and all adjournments thereof (the "Meeting"), with all powers the
undersigned would possess if personally present. The proxies are authorized to
vote as indicated on the reverse side upon the matter set forth on the reverse
side and in their discretion upon all other matters that may properly come
before the Meeting. The undersigned hereby acknowledges receipt of a copy of the
accompanying Notice of Special Meeting of Stockholders and Proxy Statement for
the Meeting and hereby revokes all proxies, if any, heretofore given by the
undersigned to others for said Meeting.

              (IMPORTANT - TO BE SIGNED AND DATED ON REVERSE SIDE)

                         PLEASE DATE, SIGN AND MAIL YOUR
                      PROXY CARD BACK AS SOON AS POSSIBLE!



                         SPECIAL MEETING OF STOCKHOLDERS

                          CORSAIR COMMUNICATIONS, INC.

                                  [DATE], 2001

                 Please Detach and Mail in the Envelope Provided

         PLEASE MARK YOUR
         /X/      VOTES AS IN
         THIS EXAMPLE.

         The Corsair Board of Directors recommends a vote FOR Proposal 1, and to
grant Proposals 2 and 3.

PROPOSAL 1.                               FOR         AGAINST         ABSTAIN

                                          /  /          /  /            /  /

Proposal 1.  Adoption of the amended and restated agreement and plan of
reorganization dated as of November 8, 2000 by and among Lightbridge, Inc.,
Corsair Communications, Inc. and Lightning Merger Corporation.

PROPOSAL 2.                               GRANT            WITHHOLD

                                          /  /             /  /

Proposal 2. Discretionary authority to vote on other matters to come before the
special meeting.

PROPOSAL 3.                               GRANT            WITHHOLD

                                          /  /             /  /

Proposal 3. Discretionary authority to postpone or adjourn the special meeting
to another date.

IF THIS PROXY IS PROPERLY EXECUTED AND RETURNED, THE SHARES REPRESENTED THEREBY
WILL BE VOTED. IF A CHOICE IS SPECIFIED WITH RESPECT TO THE MATTERS TO BE ACTED
UPON, THE SHARES WILL BE VOTED UPON THE MATTERS IN ACCORDANCE WITH THE
SPECIFICATIONS MADE. IN THE ABSENCE OF ANY SPECIFICATION, THE SHARES REPRESENTED
BY THIS PROXY WILL BE VOTED FOR PROPOSAL 1 AND TO GRANT PROPOSALS 2 AND 3.

PLEASE MARK, SIGN, DATE AND RETURN CARD PROMPTLY USING THE ENCLOSED ENVELOPE.



Signature: _________ Date: __, 200_    Signature: _________ Date: __, 200_

Note: Please date and sign exactly as name appears hereon and return promptly.
If the shares are registered in the name of two or more persons, each should
sign. Executors, trustees, guardians, custodians, administrators, attorneys and
corporate officers should add their titles.