When BLSM insiders can sell

…, or exchangeable for our common stock have entered into market standoff agreements with us and have entered or will enter into lock-up agreements under which we have agreed or will agree, subject to specific exceptions described in the section titled "Underwriting," not to offer, sell, or transfer such securities for 180 days following the date of this prospectus. We refer to such period as the lock-up period. The underwriters may, in their sole discretion and at any time or from time to time before the termination of the lock-up period release all or any portion of the securities subject to lock-up agreements. 84 Table of Contents Moreover, after this offering, certain holders of shares of our common stock will have rights, subject to specified conditions, to require us to file registration statements covering their shares or to include their shares in registration…

Common stock to be outstanding immediately after this offering 30,643,660 shares (or 32,049,910 shares if the underwriters exercise their option to purchase additional shares in full). Use of proceeds We estimate that the net proceeds to us from the sale of our common stock in this offering will be approximately $134.9 million (or approximately $155.8 million if the underwriters exercise their option to purchase additional shares in full), based on the initial public offering price of $16.00 per share, after deducting the underwriting discounts and commissions and estimated offering expenses payable by us.

Rule 10b5-1 sales plans Our directors and executive officers may adopt written plans, known as Rule 10b5-1 plans, in which they will contract with a broker to buy or sell shares of our common stock on a periodic basis. Under a Rule 10b5-1 plan, a broker executes trades pursuant to parameters established by the director or executive officer when entering into the plan, without further direction from them. The director or executive officer may amend a Rule 10b5-1 plan in some circumstances and may terminate a Rule 10b5-1 plan at any time.

…agreements between the underwriters and the lock-up parties do not apply, subject in certain cases to various conditions, to certain transactions, including (a) transfers or dispositions of lock-up securities: (i) as a bona fide gift or gifts or charitable contribution, or for bona fide estate planning purposes, (ii) by will or intestacy or any other testamentary document, (iii) to any member of the lock-up party's immediate family or to any trust for the direct or indirect benefit of the lock-up party or any immediate family member, or if the lock-up party is a trust, to a trustor, trustee, or beneficiary of the trust or to the es…

…ctors), 70 Table of Contents certain non-physician practitioners (such as physician assistants and nurse practitioners), and teaching hospitals, as well as ownership and investment interests held by physicians and their immediate family members; federal consumer protection and unfair competition laws, which broadly regulate marketplace activities and activities that potentially harm consumers; and analogous state and foreign laws and regulations, such as state anti-kickback and false claims laws, which may apply to claims involving healthcare items or services reimbursed by non-governmental third-party payors, including private insu…

Directed share program At our request, the underwriters have reserved up to 1% of the shares of common stock offered hereby, at the initial public offering price, to offer to our directors and officers and certain of our employees, business associates, investors and friends and family of our directors, officers, employees, business associates and investors. The sales will be made at our direction by J.P. Morgan Securities LLC, an underwriter of this offering, and its affiliates through a directed share program.

…f all outstanding shares of our convertible preferred stock into 18,258,960 shares of our common stock in connection with the closing of this offering and (ii) the issuance of 365,374 shares of our common stock upon the exercise of outstanding options subsequent to March 31, 2026, of which 227,514 shares remain subject to a right of repurchase as of the date of this prospectus (the Exercised Option Share Issuance), and excludes: 1,128,299 shares of our common stock issuable upon the exercise of stock options outstanding under the 2020 Equity Incentive Plan (2020 Plan) as of March 31, 2026, with a weighted-average exercise price of $…