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v3.25.4

Nature of Operations and Basis of Presentation (Details) $ / shares in Units, $ in Thousands |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | ---
May 13, 2025 USD ($) shares | May 09, 2025 USD ($) $ / shares shares | May 08, 2025 shares | Dec. 31, 2025 USD ($) $ / shares shares | Dec. 31, 2024 USD ($) $ / shares shares | May 07, 2025 $ / shares shares
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |
Common stock, shares issued (in shares) | shares | 417,470 |  | 12,904,495 | 19,579,009 | [1] | 12,904,495 | [1] | 12,904,495
Common stock, par value (in dollars per share) | $ / shares |  |  |  | $ 0.001 | [1] | $ 0.001 | [1] | $ 0.001
Exchange common units (in shares) | shares |  |  | 122,900 |  |  |  |  |
Number of shares issued in exchange for each share (in shares) |  |  | 0.0095 |  |  |  |  |
Price per share (in dollars per share) | $ / shares |  | $ 16.00 |  |  |  |  |  |
Common stock sold by the company (in shares) | shares |  | 6,250,000 |  |  |  |  |  |
Common stock sold by certain selling shareholder (in shares) | shares |  | 625,000 |  |  |  |  |  |
Proceeds from initial public offering, net of underwriting discounts and commissions | $ |  | $ 93,000 |  | $ 93,000 |  | $ 0 |  |
Underwriter commission for initial public offers | $ |  | $ 7,000 |  |  |  |  |  |
Additional shares of Common Stock (in shares) | shares | 1,031,250 |  |  |  |  |  |  |
Proceeds from sale of shares | $ | $ 16,500 |  |  |  |  |  |  |
Withholding of common stock (in shares) | shares | 234,587 |  |  |  |  |  |  |
Stock-based compensation expense | $ | $ 10,400 |  |  | $ 10,609 |  | $ 0 |  |
Amount paid for tax withheld on vesting of restricted stock | $ | $ 3,800 |  |  |  |  |  |  |
IPO |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |
Common stock, shares subscribed but unissued (in shares) | shares |  | 6,875,000 |  |  |  |  |  |
Price per share (in dollars per share) | $ / shares |  | $ 16.00 |  |  |  |  |  |
Proceeds from initial public offering, net of underwriting discounts and commissions | $ |  | $ 100,000 |  |  |  |  |  |
IPO | Selling Stockholders |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |
Proceeds from initial public offering, net of underwriting discounts and commissions | $ |  | $ 10,000 |  |  |  |  |  |
[1] | Both the number of shares outstanding and their par value have been retrospectively recast for all prior periods presented to reflect the par value of the outstanding stock of American Integrity Insurance Group, Inc. as a result of the Corporate Contribution. See Note 1 — “Nature of Operations and Basis of Presentation” and Note 15 — “Earnings Per Share.”

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