(4)

Debt

Exchangeable Senior Notes

In January 2012, the Company issued $150.0 million in principal amount of 3.5% Exchangeable Senior Notes due 2032 (the “Notes”). The Notes were issued by Corsicanto Limited, an Irish limited company acquired by Amarin in January 2012. Corsicanto Limited is a wholly-owned subsidiary of Amarin. The general, unsecured, senior obligations are guaranteed by Amarin. Net proceeds to the Company, after payment of underwriting fees and estimated expenses, were approximately $144.3 million.

The Notes have a stated interest rate of 3.5% per year, payable semiannually in arrears on January 15 and July 15 of each year beginning on July 15, 2012, and ending upon the Notes’ maturity on January 15, 2032. The Notes are subject to repurchase by the Company at the option of the holders on each of January 19, 2017, January 19, 2022, and January 19, 2027, at a price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the repurchase date. The Notes are exchangeable under certain circumstances into cash, ADSs, or a combination of cash and ADSs, at the Company’s election, with an initial exchange rate of 113.4752 ADSs per $1,000 principal amount of Notes. If the Company elected physical settlement, the Notes would initially be exchangeable into 17,021,280 ADSs. Based on the closing price of the Company’s stock at March 31, 2012, the value of the shares if converted on that date would exceed the principal amount of the Notes by $42.7 million.

Additional covenants include: (i) limitations on any future indebtedness, (ii) the timely filing of documents and reports pursuant to Section 13 or 15(d) of the Exchange Act with both the SEC and the Trustee, and (iii) maintaining the tradability of the Notes. The Company is required to use commercially reasonable efforts to procure and maintain the listing of the Notes on the Global Exchange Market operated under the supervision of the Irish Stock Exchange (or other recognized stock exchange as defined in the Note Indenture) prior to July 15, 2012. If the Notes are not freely tradable, as a result of restrictions pursuant to U.S. securities law or the terms of the Indenture or the Notes, the Company shall pay additional interest on the Notes at the rate of 0.50% per annum of the principal amount of Notes outstanding for each day during such period for which the Company’s failure to file has occurred and is continuing or for which the Notes are not freely tradable. On April 24, 2012 the Notes were admitted to the Global Exchange Market of the Irish Stock Exchange.

The Company may not redeem the Notes prior to January 19, 2017, other than in connection with certain changes in the tax law of a relevant taxing jurisdiction that results in additional amounts becoming due with respect to payments and/or deliveries on the Note. On or after January 19, 2017 and prior to the maturity date, the Company may redeem for cash all or part of the Notes at a redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. No sinking fund is provided for the Notes. If the Company undergoes a fundamental change, holders may require the Company to repurchase for cash all or part of their Notes at a repurchase price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. The Notes are the Company’s senior unsecured obligations and rank senior in right of payment to the Company’s future indebtedness that is expressly subordinated in right of payment to the Notes and equal in right of payment to the Company’s future unsecured indebtedness that is not so subordinated. The Notes are effectively junior in right of payment to future secured indebtedness to the extent of the value of the assets securing such indebtedness.

The Notes are exchangeable under certain circumstances, and the proceeds allocated to this conversion option was determined to be $23.8 million and was deducted from the initial fair value of the $150.0 million debt obligation. The conversion option will not be subsequently remeasured as long as it continues to meet conditions for equity classification. The Notes fell under Level 3 of the fair value hierarchy. The Company determined the fair value of the liability component of the Notes to be $126.2 million, and the excess of the principal amount of the liability component over the liability is the amount allocated to the conversion option and also results in a discount on the debt. The discount created from allocating proceeds to the conversion option will be amortized to interest expense using the effective interest method over the Notes’ estimated remaining life, which was calculated to be a period of twenty-four months, and the effective interest rate of the Notes is 13.5%. As of March 31, 2012, the unamortized discount created from the allocation of the proceeds to the conversion option was $21.5 million.

The Company also recorded a debt discount to reflect the value of the underwriter’s discounts and offering costs. A portion of the debt discount from underwriters discounts and offering costs was the equity and liability components of the Notes in proportion to the proceeds allocated to each component. The portion of the debt discount from underwriters discounts and offering costs allocated to the liability component is being amortized as interest expense over the estimated remaining life of the Notes of twenty-four months. As of March 31, 2012, the unamortized debt discount was $4.3 million was recorded as a direct reduction of debt on the balance sheet. The carrying value of the Notes, net of the unamortized discount, was $124.2 million. During the three months ended March 31, 2012, the Company recognized interest expense of $4.0 million related to the Notes, of which $2.3 million represents amortization of the debt discount created upon allocation of proceeds to the conversion option, $1.2 million represents contractual coupon interest, and $0.5 million represents the amortization of the discount from the underwriter’s discounts and offering costs.