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ITEM 3. PAST CONTACTS, TRANSACTIONS, NEGOTIATIONS AND AGREEMENTS

The paragraph under the caption “Arrangements with Current Executive Officers and Directors of the Company – Future Arrangements Following the Closing” on page 10 of the Schedule 14D-9 is amended and restated as follows:

Other than as described above, as of the date of this the Schedule 14D-9 and as of August 21, 2026, the date of this Amendment No. 2, none of the Company’s executive officers have (i) reached an understanding on potential employment or other retention terms with the Surviving Corporation or with Parent or Purchaser; (ii) entered into restrictive covenant agreements with the Surviving Corporation or with Parent or Purchaser, or (iii) entered into any definitive agreements or arrangements regarding employment or other retention with the Surviving Corporation or with Parent or Purchaser to be effective following the consummation of the Closing, or (iv) reached an understanding with the Surviving Corporation or with Parent or Purchaser regarding equity participation in the Surviving Corporation or Parent. However, prior to the Closing, Parent or Purchaser may initiate discussions regarding employment or other retention terms and may enter into definitive agreements regarding employment or retention for certain of the Company’s employees to be effective as of the Closing.

ITEM 4. THE SOLICITATION OR RECOMMENDATION

The second paragraph under the caption “Certain Unaudited Prospective Financial Information” on page 21 of the Schedule 14D-9 is amended and restated as follows:

As part of the Company Board’s evaluation of a potential sale of the Company and other potential strategic alternatives available to the Company (including continuing as an independent company), the Company management prepared, at the direction of the Company Board, and reviewed with the Company Board, certain unaudited prospective financial information, for the Company for fiscal years 2026 through 2045, which included certain risk-based adjustments estimated by the Company management, summarized in the table below (the “Projections”). The Projections (for the avoidance of doubt, without any alterations or adjustments) were approved by the Company Board for use and reliance by, and provided by the Company management to, Guggenheim Securities for purposes of Guggenheim Securities’ financial analysis and opinion to the Company Board, as described in “Item 4 - The Solicitation or Recommendation - Opinion of Guggenheim Securities.” For more information on the review and use of the Projections, see “Item 4 - The Solicitation or Recommendation – Background of the Offer and the Merger.” The Projections were not provided to argenx or Purchaser or any of their representatives or advisors.

The second footnote to the table under the caption “Certain Unaudited Prospective Financial Information” on page 22 of the Schedule 14D-9 is amended and restated as follows:

(2)

The calculation of tax expense assumes a tax rate of 25% and aggregate estimated cash savings from tax assets, including net operating loss carryforwards, of approximately $153 million in fiscal years 2032 through 2034.

The second bullet point under the caption “Opinion of Guggenheim Securities, LLC – Summary of Financial Analyses – Change-of-Control Financial Analyses – Discounted Cash Flow Analysis” on page 29 of the Schedule 14D-9 is amended and restated as follows:

Guggenheim Securities used a discount rate range of 11.75% - 14.50% based on its estimate of the Company’s weighted average cost of capital., using its professional judgment and experience, and used the mid-year discounting convention to discount the Company-Provided Financial Projections to a valuation date of June 30, 2026.

The third bullet point under the caption “Opinion of Guggenheim Securities, LLC – Summary of Financial Analyses – Discounted Cash Flow Analysis” on page 29 of the Schedule 14D-9 is amended and restated as follows:

In estimating the Company’s terminal/continuing value, Guggenheim Securities used an illustrative perpetual growth rate of negative 50.0%, reflecting continued decline in revenue following the assumed global loss of exclusivity for FB102 in 2043, applied to the Company’s terminal year normalized after-tax unlevered free cash flow as provided by, discussed with and approved for Guggenheim Securities’ use by the Company’s senior management.

The fifth bullet point under the caption “Opinion of Guggenheim Securities, LLC – Summary of Financial Analyses – Discounted Cash Flow Analysis” on page 29 of the Schedule 14D-9 is amended and restated as follows:

Guggenheim Securities then converted the result of the foregoing calculations to per Share equity value using diluted shares outstanding as of July 24, 2026 (based on 20.49 million basic shares outstanding and the dilutive impact, calculated using the treasury stock method) as of July 24, 2026, as provided by, discussed with and approved for Guggenheim Securities’ use by the Company’s senior management where applicable, of outstanding Company Options, Company RSUs, Company Pre-Funded Warrants and purchase rights under the Company ESPP.

The second paragraph under the caption “Opinion of Guggenheim Securities, LLC – Summary of Financial Analyses – Other Financial Reviews and Analyses Solely for Informational Reference Purposes” on page 29 of the Schedule 14D-9 is amended and restated as follows:

Guggenheim Securities noted that such precedent M&A transaction-related premia ranged from (i) 42% -79% based on the 25th to 75th percentile for the target companies’ one-day unaffected premium, which applied to the Unaffected Price of $54.78, resulted in an illustrative range of $77.79 - $98.06 per Share and (ii) 13% - 48% based on the 25th to 75th percentile for the target companies’ 52-week high closing stock prices, which applied to the 52-Week High closing price of the Shares of $59.70, resulted in an illustrative range of $67.46 - $88.36 per Share, as compared to the Offer Price of $77.00 per Share.

The fourth paragraph under the caption “Opinion of Guggenheim Securities, LLC – Summary of Financial Analyses – Other Financial Reviews and Analyses Solely for Informational Reference Purposes” on page 29 of the Schedule 14D-9 is amended and restated as follows:

Wall Street Equity Research Analyst Stock Price Targets. Guggenheim Securities reviewed selected 5 Wall Street equity research analyst stock price targets for the Company as published prior to the Unaffected Date and noted that such Wall Street equity research analyst stock price targets for the Shares were between $54.00 and $75.00 per Share, as compared to the Offer Price of $77.00 per Share.

The second paragraph under the caption “Opinion of Guggenheim Securities, LLC – Other Considerations” on page 30 of the Schedule 14D-9 is amended and restated as follows:

Pursuant to the terms of Guggenheim Securities’ engagement as the Company’s financial advisor, the Company has agreed to pay Guggenheim Securities a cash transaction fee (based on a percentage of the aggregate value associated with the Transactions) upon consummation of the Transactions, which cash transaction fee is currently estimated to be approximately $43 million. In connection with Guggenheim Securities’ engagement, the Company has agreed to pay Guggenheim Securities a cash fee of $2.0 million that became payable upon delivery of Guggenheim Securities’ opinion (which fee was not conditioned on the conclusions contained in such opinion), which will be credited against the foregoing cash transaction fee. In addition, the Company has agreed to reimburse Guggenheim Securities for certain expenses and to indemnify Guggenheim Securities against certain liabilities arising out of its engagement.

ITEM 8. ADDITIONAL INFORMATION