Notice of Section 338(g) Election - To: Former Shareholders of Diurnal Group Limited (FKA Diurnal Group PLC)

This notice is not applicable to you unless you are a U.S. person, as defined by the United States Internal Revenue Code. Generally, you are considered a U.S. person for this purpose if you (i) are a U.S. citizen, (ii) are a U.S. permanent resident (holder of a “green card”) or (iii) spend a significant amount of time in the U.S. (generally more than 183 days calculated over a three-year period). If you have questions about whether you qualify as a U.S. person or if you believe you qualify as a U.S. person, you should consult your U.S. tax advisor. If you are a U.S. person and need additional information regarding the transaction for purposes of filing your U.S. tax return, please contact Rob Weber by email at null . Purchasing Corporation: Name: Neurocrine Biosciences, Inc. Address: 12780 El Camino Real San Diego, CA 92130 Employer Identification Number: 33-0525145 Country of Incorporation: United States of America Foreign Targets: Name: Diurnal Group Limited (FKA Diurnal Group PLC) Address: Cardiff Medicentre, Heath Park Cardiff, CF14 4UJ United Kingdom Employer Identification Number: Not applicable Country of Incorporation: United Kingdom See attached for additional foreign targets THIS DOCUMENT SERVES AS NOTICE OF AN ELECTION UNDER SECTION 338 FOR THE ABOVE CITED FOREIGN TARGETS THE STOCK OF WHICH YOU EITHER HELD OR SOLD UNDER THE CIRCUMSTANCES DESCRIBED IN TREASURY REGULATIONS SECTION 1.338- 2(e)(4). FOR POSSIBLE UNITED STATES FEDERAL INCOME TAX CONSEQUENCES UNDER SECTION 551, 951, 1248, OR 1293 OF THE INTERNAL REVENUE CODE OF 1986 THAT MAY APPLY TO YOU, SEE TREASURY REGULATIONS SECTION 1.338-9(b). YOU MAY BE REQUIRED TO ATTACH THE INFORMATION ATTACHED TO THIS NOTICE TO CERTAIN RETURNS. Attachment: Name: Diurnal Limited Address: Cardiff Medicentre, Heath Park Cardiff, CF14 4UJ United Kingdom Employer Identification Number: Not applicable Country of Incorporation: United Kingdom Name: Diurnal Europe B.V. Address: Van Heuven Goedhartlaan 935 A 1181 LD Amstelveen Netherlands Employer Identification Number: Not applicable Country of Incorporation: Netherlands