USNA

On May 13, 2008, Dr. Wentz, Gull Holdings, Ltd., an Isle of Man company indirectly owned and controlled by Dr. Wentz ("Gull Holdings"), together with certain other persons (Dr. Wentz, Gull Holdings and such other persons, collectively, the "Original Reporting Persons") announced their intention to commence a tender offer (the "Offer") to purchase all of the outstanding Shares of the Issuer not owned by the Original Reporting Persons for $26.00 per share in cash through Unity Acquisition Corp., a newly formed acquisition vehicle ("Unity Acquisition"). On July 16, 2008, Gull Holdings and Unity Acquisition issued a press release announcing the termination of the Offer and disclosing that no Shares were accepted for payment by the Purchaser in connection with the Offer. As a result of the termination of the Offer on July 16, 2008, the Original Reporting Persons ceased to be a group (as disclosed in Item 11 of Amendment No. 8 to the Schedule TO filed by the Original Reporting Persons with the Commission on July 16, 2008 in connection with the Offer) and the Original Reporting Persons other than Dr. Wentz and Gull Holdings ceased to be reporting persons for purposes of this Schedule 13D. From July 16, 2008 through November 13, 2013, Gull Holdings sold an aggregate of 1,263,285 Shares (not including Shares sold in cashless exercises, or following receipt upon exercise, of equity compensation Options (as defined below) and SSARs (as defined below) in open market transactions for aggregate gross proceeds of approximately $53,472,263.81. On July 21, 2008, the Issuer granted to Dr. Wentz equity incentive compensation in the form of stock-settled stock appreciation rights relating to 500,000 Shares (the "SSARs"), with an exercise price of $26.06 per Share. At various times between September 14, 2012 and March 4, 2014, Dr. Wentz exercised the SSARs, which had an aggregate market value of $25,298,771.50 at the time of exercise, and received an aggregate of 233,342 Shares (which were sold in open market transactions in connection with settlement of such exercises). Between November 2013 and April 2015, Dr. Wentz changed the form of his indirect ownership of the Shares deemed beneficially owned by him by causing Gull Holdings to transfer all of the Shares held by it to Gull Global (the "Gull Reorganization"). To effect the Gull Reorganization, (i) on or about November 29, 2013 Gull Global, which at the time was indirectly wholly owned by the Gull Trust and controlled by Dr. Wentz, acquired 131,788 Shares as a contribution from Gull Holdings, and Gull Global thereby became a reporting person for purposes of this Schedule 13D (Gull Global in such capacity, and together with Dr. Wentz and, as applicable, Gull Holdings, the "Reporting Persons"), (ii) on or about February 20, 2014, Gull Global acquired 100% of the share capital of Gull Holdings, and thereby acquired indirect beneficial ownership of the remaining Shares owned directly by Gull Holdings, and (iii) on or about April 1, 2015, Gull Holdings transferred to Gull Global 6,443,322 Shares and Gull Holdings ceased to be a reporting person for purposes of this Schedule 13D. From time to time between April 9, 2014 through June 24, 2024, Gull Global sold an aggregate of 4,083,419 Shares (not including Shares sold in cashless exercises, or following receipt upon exercise, of equity compensation Options and SSARs) in open market transactions for aggregate gross proceeds of approximately $367,184,913.48. Between December 4, 2014 and December 9, 2014 Dr. Wentz exercised, in cashless exercise transactions, options for 280,000 Shares, which he had been granted as equity compensation in 2005, which had an aggregate market value of $28,876,643.71 at the time of exercise and resulted in aggregate net cash proceeds of $12,534,370.59 to Dr. Wentz. The options had an exercise price of $39.18 per share. From time to time between May 7, 2009 and September 3, 2025 the Reporting Persons also made charitable donations and other gifts of an aggregate of 1,313,171 Shares. Since the termination of the Offer in 2008, the Reporting Persons have held (and, until Gull Holdings ceased to be a reporting person for purposes of this Schedule 13D, Gull Holdings held), and the Reporting Persons intend to continue to hold, their Shares for investment purposes. However, the Reporting Persons have sold and will continue to sell, some of their Shares through sales in the open market, in privately negotiated transactions or otherwise, on such terms and at such times as the Reporting Persons may deem advisable, for liquidity purposes. Some of such sales have been made pursuant to Rule 10b5-1 trading plans. The Reporting Persons also expect to continue to make charitable donations of Common Stock. In addition, the Reporting Persons may formulate plans or proposals for, hold discussions with the Issuer's management, the Issuer's Board of Directors, the Issuer's stockholders and other parties about, and reserve the right to explore, or make plans or proposals relating to, transactions, discussions or actions which relate to or would result in any of the matters specified in clauses (a) through (j) of Item 4 of Schedule 13D. The Reporting Persons' consideration or discussion of any action would be based on their own assessment of various relevant considerations and any subsequent developments affecting the Issuer and its prospects.

On May 13, 2008, Dr. Wentz, Gull Holdings, Ltd., an Isle of Man company indirectly owned and controlled by Dr. Wentz ("Gull Holdings"), together with certain other persons (Dr. Wentz, Gull Holdings and such other persons, collectively, the "Original Reporting Persons") announced their intention to commence a tender offer (the "Offer") to purchase all of the outstanding Shares of the Issuer not owned by the Original Reporting Persons for $26.00 per share in cash through Unity Acquisition Corp., a newly formed acquisition vehicle ("Unity Acquisition"). On July 16, 2008, Gull Holdings and Unity Acquisition issued a press release announcing the termination of the Offer and disclosing that no Shares were accepted for payment by the Purchaser in connection with the Offer. As a result of the termination of the Offer on July 16, 2008, the Original Reporting Persons ceased to be a group (as disclosed in Item 11 of Amendment No. 8 to the Schedule TO filed by the Original Reporting Persons with the Commission on July 16, 2008 in connection with the Offer) and the Original Reporting Persons other than Dr. Wentz and Gull Holdings ceased to be reporting persons for purposes of this Schedule 13D. From July 16, 2008 through November 13, 2013, Gull Holdings sold an aggregate of 1,263,285 Shares (not including Shares sold in cashless exercises, or following receipt upon exercise, of equity compensation Options (as defined below) and SSARs (as defined below) in open market transactions for aggregate gross proceeds of approximately $53,472,263.81. On July 21, 2008, the Issuer granted to Dr. Wentz equity incentive compensation in the form of stock-settled stock appreciation rights relating to 500,000 Shares (the "SSARs"), with an exercise price of $26.06 per Share. At various times between September 14, 2012 and March 4, 2014, Dr. Wentz exercised the SSARs, which had an aggregate market value of $25,298,771.50 at the time of exercise, and received an aggregate of 233,342 Shares (which were sold in open market transactions in connection with settlement of such exercises). Between November 2013 and April 2015, Dr. Wentz changed the form of his indirect ownership of the Shares deemed beneficially owned by him by causing Gull Holdings to transfer all of the Shares held by it to Gull Global (the "Gull Reorganization"). To effect the Gull Reorganization, (i) on or about November 29, 2013 Gull Global, which at the time was indirectly wholly owned by the Gull Trust and controlled by Dr. Wentz, acquired 131,788 Shares as a contribution from Gull Holdings, and Gull Global thereby became a reporting person for purposes of this Schedule 13D (Gull Global in such capacity, and together with Dr. Wentz and, as applicable, Gull Holdings, the "Reporting Persons"), (ii) on or about February 20, 2014, Gull Global acquired 100% of the share capital of Gull Holdings, and thereby acquired indirect beneficial ownership of the remaining Shares owned directly by Gull Holdings, and (iii) on or about April 1, 2015, Gull Holdings transferred to Gull Global 6,443,322 Shares and Gull Holdings ceased to be a reporting person for purposes of this Schedule 13D. From time to time between April 9, 2014 through June 24, 2024, Gull Global sold an aggregate of 4,083,419 Shares (not including Shares sold in cashless exercises, or following receipt upon exercise, of equity compensation Options and SSARs) in open market transactions for aggregate gross proceeds of approximately $367,184,913.48. Between December 4, 2014 and December 9, 2014 Dr. Wentz exercised, in cashless exercise transactions, options for 280,000 Shares, which he had been granted as equity compensation in 2005, which had an aggregate market value of $28,876,643.71 at the time of exercise and resulted in aggregate net cash proceeds of $12,534,370.59 to Dr. Wentz. The options had an exercise price of $39.18 per share. From time to time between May 7, 2009 and September 3, 2025 the Reporting Persons also made charitable donations and other gifts of an aggregate of 1,313,171 Shares. Since the termination of the Offer in 2008, the Reporting Persons have held (and, until Gull Holdings ceased to be a reporting person for purposes of this Schedule 13D, Gull Holdings held), and the Reporting Persons intend to continue to hold, their Shares for investment purposes. However, the Reporting Persons have sold and will continue to sell, some of their Shares through sales in the open market, in privately negotiated transactions or otherwise, on such terms and at such times as the Reporting Persons may deem advisable, for liquidity purposes. Some of such sales have been made pursuant to Rule 10b5-1 trading plans. The Reporting Persons also expect to continue to make charitable donations of Common Stock. In addition, the Reporting Persons may formulate plans or proposals for, hold discussions with the Issuer's management, the Issuer's Board of Directors, the Issuer's stockholders and other parties about, and reserve the right to explore, or make plans or proposals relating to, transactions, discussions or actions which relate to or would result in any of the matters specified in clauses (a) through (j) of Item 4 of Schedule 13D. The Reporting Persons' consideration or discussion of any action would be based on their own assessment of various relevant considerations and any subsequent developments affecting the Issuer and its prospects.