A Form 4 filed on August 4, 2026 discloses that Steven L. Hoerter, President and CEO of MBX Biosciences, Inc. (NASDAQ: MBX), received grants of restricted stock units and stock options on August 3, 2026.

Key Highlights

  • RSU grant: Hoerter acquired 71,000 restricted stock units at a price of $0, bringing his directly held common stock to 82,938 shares.
  • RSU vesting schedule: 25% of the RSUs vest annually over four years on each of July 13, 2027, 2028, 2029, and 2030, subject to continued service.
  • Stock option grant: Hoerter was granted options to purchase 331,000 shares of common stock at an exercise price of $64.41, expiring August 3, 2036.
  • Option vesting schedule: 25% of the options vest on July 13, 2027, with the remainder vesting in 36 equal monthly installments thereafter, subject to continued service.
  • Indirect holdings: Hoerter also holds 20,000 shares indirectly through the Steven L. Hoerter Revocable Trust dated November 2, 2018, for which he serves as trustee.

Details of Steven Hoerter's August 2026 Equity Grants at MBX Biosciences

According to the filing, Hoerter received two separate equity awards on August 3, 2026. The first was a grant of 71,000 restricted stock units classified as an acquisition at $0 price. Following this transaction, the filing reports his direct beneficial ownership of common stock at 82,938 shares. The RSUs are scheduled to vest in four equal annual installments of 25% each, on July 13 of 2027, 2028, 2029, and 2030, contingent on continued service on each vesting date.

The second award was a stock option granting Hoerter the right to purchase 331,000 shares of common stock at an exercise price of $64.41 per share, with an expiration date of August 3, 2036. The filing states that 25% of the shares subject to the option award will vest on July 13, 2027, and the remaining 75% will vest in 36 equal monthly installments thereafter, also subject to continued service. The price of the derivative security is reported as $0, and Hoerter directly holds 331,000 derivative securities following this transaction.

In addition to his direct holdings, the filing notes that 20,000 shares of common stock are held indirectly through the Steven L. Hoerter Revocable Trust dated November 2, 2018. The filing states that Hoerter "disclaims beneficial ownership except to the extent of any pecuniary interest therein, and this report shall not be deemed an admission that such shares are beneficially owned by him for Section 16 or any other purpose." The Form 4 was signed by John W. Smither as Attorney-in-Fact on August 4, 2026.

What Was Disclosed

The filing discloses two equity grants to MBX Biosciences' President and CEO on August 3, 2026: 71,000 RSUs vesting over four years and stock options covering 331,000 shares at $64.41, expiring in 2036, both subject to continued service conditions.