LIGHTBRIDGE Corp — Director's Dealing 2013

Oct 29, 2013

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: LIGHTBRIDGE Corp (LTBR)
CIK: 0001084554
Period of Report: 2013-10-22

Reporting Person: MARXE AUSTIN W & GREENHOUSE DAVID M (10% Owner)

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	2378312	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Warrants	$9	2017-07-27	Common Stock (454546)		Indirect
Warrants	$2.3	2021-04-25	Common Stock (571428)		Indirect

Footnotes

F1: This is a joint filing by Austin W. Marxe (Marxe) and David M. Greenhouse (Greenhouse). They share voting and investment control over all securities owned by Special Situations Fund III QP, L.P. (QP), Special Situations Cayman Fund, L.P. (Cayman) and Special Situations Private Equity Fund, L.P. (PE). 1,486,442 shares of Common Stock are held by QP, 497,386 shares of Common Stock are held by Cayman, 394,484 shares of Common Stock are held by PE. The interest of Marxe and Greenhouse in the shares of Common Stock owned by QP, Cayman and PE is limited to the extent of his pecuniary interest.

F2: This is a joint filing by Austin W. Marxe (Marxe) and David M. Greenhouse (Greenhouse). They share voting and investment control over all securities owned by Special Situations Fund III QP, L.P (QP), Special Situations Cayman Fund, L.P. (Cayman) and Special Situations Private Equity Fund, LP (PE). 357,143 Warrants are owned by QP 120,000 Warrants are owned by Cayman and 94,285 Warrants are owned by PE. The interest of Marxe and Greenhouse in the shares of Warrants owned by QP, Cayman and PE are limited to the extent of his pecuniary interest

F3: This is a joint filing by Austin W. Marxe (Marxe) and David M. Greenhouse (Greenhouse). They share voting and investment control over all securities owned by Special Situations Fund III QP, L.P (QP), Special Situations Cayman Fund, L.P. (Cayman) and Special Situations Private Equity Fund, LP (PE). 284,091 Warrants are owned by QP, 94,697 Warrants are owned by Cayman and 75,758 Warrants are owned by PE. The interest of Marxe and Greenhouse in the shares of Warrants owned by QP, Cayman and PE are limited to the extent of his pecuniary interest.

F4: The warrants described above may be exercised to the extent that the total number of shares of Common Stock then beneficially owned does not exceed4.99% of the outstanding shares. The holder may request an increase of up to 9.99% of the outstanding shares, effective on the 61st day after notice is given to the Company.