Every Form 4 that Moleculin Biotech, Inc. (MBRX) has filed with the SEC in the last 12 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A Form 4 covers the transactions officers, directors and large holders report, so if you follow MBRX and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full MBRX filings page.
At Moleculin Biotech, Inc. (MBRX), Chief Science Officer Donald H. Picker received an employment-related grant of 250,000 options to buy common stock on October 15, 2026. The options have an exercise price of $0.3701 per share, and his direct option holdings after the grant were 789,595. Half of the grant vests on the grant date; the other half vests in 18 equal installments over 18 months. The options expire October 15, 2036.
Moleculin Biotech, Inc. CEO and President Walter V. Klemp received grants of 415,000 options and 415,000 restricted stock units on October 15, 2026. The options have a $0.3701 exercise price and expire October 15, 2036; 2,341,335 options were reported following the grant. On the same date, 207,500 restricted stock units converted into common shares, and 48,659 shares were withheld for taxes upon vesting at $0.3701 per share. The awards vest 50% on grant and the remaining 50% in 18 equal installments over 18 months.
Moleculin Biotech, Inc. Chief Financial Officer Jonathan P. Foster received an employment-related grant of 260,000 stock options, exercisable at $0.3701 per share and expiring October 15, 2036, plus 260,000 restricted stock units. On October 15, 2026, 130,000 RSUs converted one-for-one into common stock, and 30,485 shares were withheld for taxes upon vesting at $0.3701 per share. The options and RSUs vest 50% on grant and 50% in 18 equal installments over 18 months.
On August 3, 2026, Moleculin Biotech, Inc. Chief Financial Officer Jonathan P. Foster purchased 293,333 shares of common stock and 879,999 Series I Warrants in a public offering at a combined price of $0.75 per one share of common stock and three accompanying warrants. Following these transactions, he directly held 305,673 shares of common stock and 1,027,717 Series I Warrants to purchase common stock, which are reported with an expiration date of August 3, 2031.
Moleculin Biotech, Inc. director, CEO and President Walter V. Klemp reported acquiring 533,333 shares of common stock in a public offering, together with Series I warrants to purchase 1,599,999 shares. The securities were bought at a combined purchase price of $0.75 per one share of common stock and three accompanying warrants. Following these transactions, he directly holds 564,340 common shares and 1,926,335 Series I warrants, which are exercisable for common stock and expire on August 3, 2031.
Moleculin Biotech, Inc. reports that Chief Science Officer Donald H. Picker purchased 173,333 shares of common stock and Series I Warrants to purchase 519,999 shares on August 3, 2026, in a public offering at a combined purchase price of $0.75 per one share and three warrants. Following these transactions, he directly holds 174,086 common shares and 539,595 Series I Warrants.
Moleculin Biotech, Inc. Chief Science Officer Donald H. Picker reported routine equity compensation activity involving restricted stock units (RSUs). On June 20 and June 22, he exercised RSUs to acquire a total of 115 shares of common stock at a conversion price of $0.00 per share.
Across both dates, 34 common shares were withheld at prices of $2.88 and $3.12 per share to cover tax obligations upon RSU vesting, a non‑market disposition. Following these transactions, he directly holds 753 shares of common stock and 19,596 RSUs that convert into common stock on a one‑for‑one basis.
Moleculin Biotech, Inc. CEO and President Walter V. Klemp reported routine equity compensation activity involving restricted stock units and related tax withholding. On June 20 and June 22, restricted stock units converted into a total of 510 shares of common stock at a conversion price of $0.00 per share. To cover tax obligations on these vestings, a total of 125 common shares were disposed of via tax-withholding transactions, rather than open-market sales. After these transactions, Klemp directly held 31,007 shares of common stock and continued to hold a substantial equity position through 326,336 restricted stock units, as well as 250,002 shares of common stock underlying Series E warrants.
Moleculin Biotech, Inc. Chief Financial Officer Jonathan P. Foster reported routine equity compensation activity involving restricted stock units and related tax withholding. On June 20 and June 22, 2026, restricted stock units converted into a total of 283 shares of common stock at a conversion price of $0.00 per share.
To cover tax obligations on these vestings, 72 shares of common stock were disposed of at prices of $2.88 and $3.12 per share through tax-withholding dispositions, not open-market sales. Following these transactions, Foster directly holds 12,340 shares of common stock and 147,718 derivative securities, which include 100,003 shares of common stock underlying Series E warrants.
Moleculin Biotech (MBRX) filed a Form 4 for EVP & CFO Jonathan P. Foster reporting equity awards dated 11/12/2025. The filing lists a stock option for 600,000 shares at an exercise price of $0.49, expiring 11/12/2035, vesting in four equal annual installments beginning on the first anniversary. It also reports 400,000 performance-based RSUs that vest in 20% increments upon achievement of specified clinical milestones; 100% vest upon a change of control as defined in the 2024 Stock Plan. Following these transactions, derivative securities beneficially owned were 2,017,695, held directly.
Moleculin Biotech (MBRX) disclosed insider equity awards to its CEO and President on 11/12/2025. The filing reports a stock option grant for 830,000 shares at an exercise price of $0.49, vesting in four equal annual installments beginning on the first anniversary of the grant, subject to continued service.
The CEO also received 750,000 performance-based restricted stock units, each representing one share. These RSUs vest in 20% increments upon achievement of specified clinical milestones, and 100% vest upon a change of control as defined in the 2024 Stock Plan. Following these awards, the form shows 3,960,731 derivative securities beneficially owned.
Moleculin Biotech (MBRX) reported a director’s stock option grant on a Form 4. The filing shows 150,000 stock options with an exercise price of $0.49, granted on 11/12/2025. These options vest on 11/12/2026, subject to continued Board service, and expire on 11/12/2035.
Following this transaction, the filing lists 164,001 derivative securities beneficially owned, held in direct ownership. The options were issued in connection with the reporting person’s Board of Director service.
Moleculin Biotech (MBRX) reported a director’s grant of 150,000 stock options (Transaction Code A) at an exercise price of $0.49 on November 12, 2025.
The options vest on November 12, 2026, subject to continued Board service, and expire on November 12, 2035. Following this grant, the reporting person beneficially owned 165,336 derivative securities, held directly. The filing notes the options were issued in connection with Board service.
Moleculin Biotech (MBRX) reported a director’s grant of stock options. The filing shows 150,000 stock options (right to buy) at an exercise price of $0.49 per share on 11/12/2025, coded “A” for award. These options vest on 11/12/2026 and expire on 11/12/2035, issued in connection with Board service. Following this transaction, the director beneficially owned 165,169 derivative securities, held directly.
Moleculin Biotech (MBRX) disclosed an insider equity transaction by its Chief Science Officer. On 11/04/2025, 8,750 restricted stock units converted to common stock, and 2,131 shares were withheld at $0.497 for taxes upon vesting. Following these transactions, the reporting person beneficially owned 16,771 shares directly. Derivative holdings show 95,508 restricted stock units remaining. The RSUs relate to a 35,000-unit grant made on November 4, 2024, scheduled to vest in four equal annual installments beginning on the first anniversary of the grant date.
Moleculin Biotech (MBRX) reported an insider equity event by its CEO and President/Director. On 11/04/2025, 28,750 shares of common stock were acquired upon the vesting and conversion of restricted stock units (transaction code M). The filing also shows 7,001 shares were disposed (code F) to cover taxes at $0.497 per share.
Following these transactions, the executive directly beneficially owned 765,356 shares of common stock. The derivative holdings section lists 2,380,731 derivative securities beneficially owned after the reported transaction. The RSUs convert one-for-one into common stock, and the underlying grant from November 4, 2024 totals 115,000 RSUs vesting in four equal annual installments beginning on the first anniversary.
Moleculin Biotech (MBRX) reported an officer equity transaction. On 11/04/2025, Chief Financial Officer Jonathan P. Foster settled 20,625 restricted stock units that converted into common stock on a one-for-one basis (code M).
To cover taxes upon vesting, 5,023 shares were withheld at a price of $0.497 per share. Following these transactions, Mr. Foster directly owns 303,189 shares of Moleculin common stock.
The RSUs relate to an award granted on November 4, 2024 of 82,500 RSUs, vesting in four equal annual installments beginning on the first anniversary of the grant date.