Lightbridge Reaffirms Guidance for Fourth Quarter 2005

Company expects revenue and EPS to be inline with guided range

Burlington, MA – December 13, 2005 – Lightbridge, Inc. (NASDAQ: LTBG), a leading e-commerce, analytics and decisioning company, today reaffirmed its revenue and earnings guidance given on October 26, 2005. The reiterated guidance is as follows:

• Estimated total revenue will be in the range of $25.5 to $27.0 million, with Authorize.Net expected to contribute in the range of $12.0 to $12.5 million.

• Earnings per share is expected to be between $0.06 and $0.10.

About Lightbridge

Lightbridge, Inc. (NASDAQ:LTBG) is a leading analytics, decisioning and e-commerce company that businesses trust to manage customer transactions. Lightbridge adds value to fraud screening, credit qualification and payment authorization services. Lightbridge solutions leverage intelligent automated systems and human expertise, delivered primarily through the efficiencies and cost savings of an outsourced business model. Businesses use Lightbridge to make smarter decisions, deliver better services, provide secure payments, reduce costs and enhance the lifetime value of their customers. For more information, visit www.lightbridge.com.

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Contacts

Lynn Ricci
Investor & Media Relations
Lightbridge, Inc.
781/359-4854
lricci@lightbridge.com

Note to Editors: LIGHTBRIDGE is a registered trademark and the Lightbridge logo is a trademark of Lightbridge Inc. All other trademarks and registered trademarks are the properties of their respective owners.

Forward-looking Statements

Certain statements in this news release that are not historical facts, including, without limitation, those relating to the Company’s fourth quarter of 2005 financial guidance are forward-looking statements that involve risks and uncertainties. Such statements are based upon the current beliefs and expectations of the management of the Company. Actual results may vary materially from those contained in forward-looking statements based on a number of factors including, without limitation, (i) dependence on a limited number of clients, (ii) the Company’s revenue concentration in the wireless telecommunications business and the declining subscriber growth rate in that business, (iii) continuing rapid change in the telecommunications industry, payment processing industry, and other markets in which the Company does business that may affect both the Company and its clients, (iv) current and future economic conditions generally and particularly in the telecommunications and payment processing industry, (v) uncertainties about the Company’s ability to execute on, and about the impact on the Company’s business and operations of, its objectives, plans or strategies as a result of potential technological, market or competitive factors, (vi) the impact of restructuring and other charges on the Company’s business and operations, (vii) integration, employee retention, recognition of cost and other benefits and revenue synergies, and other risks associated with acquisitions, (viii) the industry risks associated with Authorize.Net’s business and operations including, without limitation, illegal or improper uses of Authorize.Net’s payment system, unauthorized intrusions and attacks on Authorize.Net’s payment system that may impair the operation of its payment systems, changes in or failures to comply with credit card association rules, governmental regulation and the application of existing laws to Authorize.Net’s business and dependence on relationships with third party payment processors, (ix) the factors disclosed in the Company’s filings with the U.S. Securities and Exchange Commission including, without limitation, its 2004 Annual Report on Form 10-K and most recent Quarterly Report on Form 10-Q. The Company undertakes no obligation to update any forward-looking statements.