Company: SION
Filing Date: 2025-02-03
Form Type: S-1/A
Source: 0001193125-25-018825
Chunk: 265

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-02-03
Form: S-1/A
Chunk 265
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 shares or shares that we reacquire. The shares of common stock underlying any
awards under the 2025 Plan and the 2020 Plan that are forfeited, cancelled, held back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, reacquired by us prior to vesting, satisfied without the issuance of
stock or are otherwise terminated (other than by exercise) will be added back to the shares of common stock available for issuance under the 2025 Plan.

The maximum number of shares of common stock that may be issued in the form of incentive stock options shall not exceed the Initial Limit, cumulatively
increased on January 1, 2026 and on each January 1 thereafter by the lesser of the Annual Increase for such year or 5,060,000 shares of common stock.

The grant date fair value of all awards made under our 2025 Plan and all other cash compensation paid by us to any
non-employee director in any calendar year for services as a non-employee director shall not exceed $750,000; provided, however, that such amount shall be $1,000,000 for
the calendar year in which the applicable non-employee director is initially elected or appointed to the board of directors.

The 2025 Plan will be administered by our compensation committee. Our administrator has the full power to select, from among the individuals eligible
for awards, the individuals to whom awards will be granted and the number of shares subject to such awards, to make any combination of awards to participants, to accelerate at any time the exercisability or vesting of any award and to determine the
specific terms and conditions of each award, subject to the provisions of the 2025 Plan. Persons eligible to participate in the 2025 Plan will be those employees, non-employee directors and consultants as
selected from time to time by our administrator in its discretion.

The 2025 Plan permits the granting of both options to purchase common stock
intended to qualify as incentive stock options under Section 422 of the Code and options that do not so qualify. The option

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exercise price of each option will be determined by our administrator but may not be less than 100% of the closing price of our common stock on the date of grant (or, if no closing price is
reported on that date, the closing price on the immediately preceding date on which a closing price was reported) (110% in the case of certain incentive stock options)