Company: GHRS
Filing Date: 2025-02-05
Form Type: 424B5
Source: 0001140361-25-003183
Chunk: 18

Company: GH Research PLC
Filing Date: 2025-02-05
Form: 424B5
Chunk 18
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 were also a PFIC (any such entity is herein referred to as a “Lower-tier PFIC”), a U.S. Holder would be deemed to own a proportionate amount (by value) of the shares of each Lower-tier PFIC and would be subject to U.S. federal income tax according to the rules described in the subsequent paragraph on (i) certain distributions by a Lower-tier PFIC; and (ii) dispositions of shares of Lower-tier PFICs, in each case as if such holder held such shares directly, even though such holder will not have received the proceeds of those distributions or dispositions.

If we were a PFIC for any taxable year during which a U.S. Holder held any of our ordinary shares, such holder would generally be subject to adverse tax consequences. Generally, gain recognized upon a disposition (including, under certain circumstances, a pledge) of our ordinary shares would be allocated ratably over a U.S. Holder’s holding period for the ordinary shares. The amounts allocated to the taxable year of disposition and to years before we became a PFIC would be taxed as ordinary income. The amount allocated to each other taxable year would be subject to tax at the highest rate in effect for that taxable year for individuals or corporations, as appropriate, and an interest charge would be imposed on the tax on such amount. Further, to the extent that any distributions received on a U.S. Holder’s ordinary shares during a taxable year exceeded 125% of the average of the annual distributions on those shares during the preceding three years or such holder’s holding period, whichever was shorter, those distributions would be subject to taxation in the same manner as gain.

Alternatively, if we were a PFIC and if the ordinary shares were “regularly traded” on a “qualified exchange,” a U.S. Holder may avoid the general PFIC tax consequences discussed above if such U.S. Holder makes a

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mark-to-market election with respect to the ordinary shares at the close of the first taxable year in which such holder holds our ordinary shares. Nasdaq, on which the ordinary shares are listed, is a qualified exchange for this purpose. Once made, the election cannot be revoked without the consent of the IRS unless the ordinary shares cease to be marketable.

If a U.S. Holder makes the mark-to-market election with respect to the first taxable year that we are a PFIC and the U.S. Holder holds our ordinary shares, such holder will