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                                                                    Exhibit 31.2

      I, Timothy C. O'Brien, Chief Financial Officer of Lightbridge,
            Inc., certify that:

      1. I have reviewed this Amendment No. 1 to Annual Report on
            Form 10-K of Lightbridge, Inc.;

      2. Based on my knowledge, this report does not contain any
            untrue statement of a material fact or omit to state a material fact
            necessary to make the statements made, in light of the circumstances
            under which such statements were made, not misleading with respect
            to the period covered by this report;

      3. Based on my knowledge, the financial statements, and other
            financial information included in this report, fairly present in all
            material respects the financial condition, results of operations and
            cash flows of the registrant as of, and for, the periods presented
            in this report;

      4. The registrant's other certifying officers and I are
            responsible for establishing and maintaining disclosure controls and
            procedures (as defined in Exchange Act Rules 13a-15(e) and
            15d-15(e)) and internal control over financial reporting (as defined
            in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant
            and have:

            a)    Designed such disclosure controls and procedures to ensure, or
                  caused such disclosure controls and procedures to be designed
                  under our supervision, to ensure that material information
                  relating to the registrant, including its consolidated
                  subsidiaries, is made known to us by others within those
                  entities, particularly during the period in which this report
                  is being prepared;

            b)    Designed such internal control over financial reporting, or
                  caused such internal control over financial reporting to be
                  designed under our supervision, to provide reasonable
                  assurance regarding the reliability of financial reporting and
                  the preparation of financial statements for external purposes
                  in accordance with generally accepted accounting principles;

            c)    Evaluated the effectiveness of the registrant's disclosure
                  controls and procedures and presented in this report our
                  conclusions about the effectiveness of the disclosure controls
                  and procedures, as of the end of the period covered by this
                  report based on such evaluation; and

            d)    Disclosed in this report any change in the registrant's
                  internal control over financial reporting that occurred during
                  the registrant's most recent fiscal quarter (the registrant's
                  fourth quarter in the case of an annual report) that has
                  materially affected, or is reasonably likely to materially
                  affect, the registrant's internal control over financial
                  reporting; and

      5. The registrant's other certifying officers and I have
            disclosed, based on our most recent evaluation of internal control
            over financial reporting, to the registrant's auditors and the audit
            committee of registrant's board of directors (or persons performing
            the equivalent functions):

            a)    All significant deficiencies and material weaknesses in the
                  design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  registrant's ability to record, process, summarize and report
                  financial information; and

            b)    Any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  registrant's internal control over financial reporting.

Date: February 17, 2006
                                        /s/ Timothy C. O'Brien
                                 ---------------------------------------------
                                          Timothy C. O'Brien
                                        Chief Financial Officer
                                     (Principal Financial Officer)