Korro Bio, Inc. filings document the regulatory record of a biopharmaceutical company developing RNA-editing genetic medicines through its OPERA® platform. Its 8-K reports disclose operating and financial results, corporate presentations, clinical and regulatory program updates, capital-structure activity, and material events tied to its RNA-editing pipeline.
The company’s filings also cover proxy governance, executive compensation, equity incentive and inducement arrangements, employment agreements, and material collaboration and license agreements. Program-related disclosures focus on KRRO-121, hyperammonemia in urea cycle disorders and hepatic encephalopathy, GalNAc-conjugated oligonucleotide research, alpha-1 antitrypsin deficiency, risk factors, and the financing and governance framework supporting Korro Bio’s development-stage operations.
Korro Bio, Inc. has a significant shareholder group led by Balyasny Asset Management L.P. and related entities, which report beneficial ownership of 951,783 shares of Korro Bio common stock. This position represents approximately 6.60% of the outstanding common shares, based on 14,422,571 shares outstanding as of May 4, 2026.
The shares are held through two Cayman Islands investment vehicles: Atlas Diversified Master Fund, Ltd. with 411,729 shares and Atlas Private Holdings (Cayman) Ltd with 540,054 shares. Each reporting person, including Balyasny Asset Management L.P., BAM GP LLC, Balyasny Asset Management Holdings LP, Dames GP LLC, and Dmitry Balyasny, is deemed to have sole voting and dispositive power over the full 951,783 shares and no shared power.
Korro Bio, Inc. director Jean Francois Formela reported indirect sales of Korro Bio common stock on August 11, 2026. A total of 2,143 shares were sold at a weighted average price of $13.96 per share, in transactions executed under a Rule 10b5-1 trading plan adopted on April 8, 2026. The sold shares were held by Atlas Venture Fund XI, L.P. and Atlas Venture Opportunity Fund II, L.P., and Formela disclaims Section 16 beneficial ownership except to the extent of any pecuniary interest.
Korro Bio, Inc. reported insider purchases of common stock by entities associated with Lynx1 Capital Management LP and Weston Nichols. On August 6, 2026, Lynx1 Master Fund LP purchased 5,222 shares at a weighted average price of $11.3998 per share, and on August 10, 2026 it purchased 1,462 shares at a weighted average price of $13.1869, for a total of 6,684 shares, all held indirectly. The investment manager and Mr. Nichols disclaim beneficial ownership except to the extent of any pecuniary interest.
KRRO common shareholders have filed a notice to sell shares under Rule 144. The filing covers 368 shares of common stock, with an aggregate market value of $4,964.32, and notes 14,725,646 shares outstanding as of 08/11/2026 on Nasdaq. The notice also lists recent market sales by affiliated funds between May and July 2026 as background disclosure.
KRRO common stock holders filed to sell shares under a resale notice. The planned transaction lists 1,775 shares of common stock to be sold through Merrill Lynch on Nasdaq. Atlas Venture Fund XI, L.P. and Atlas Venture Opportunity Fund II, L.P. also report multiple prior common stock sales over the past three months with varying sizes and proceeds.
Korro Bio, an RNA‑editing biopharma, reported no collaboration revenue for the three or six months ended June 30, 2026, versus $1,460 thousand and $4,010 thousand a year earlier, reflecting a 12‑month pause of its Novo Nordisk partnership. Net loss narrowed to $18,916 thousand for the quarter and $38,541 thousand for the first half, driven mainly by lower research and development spending.
Research and development expense fell to $26,539 thousand for the first half of 2026 from $39,874 thousand, and general and administrative expense declined to $14,007 thousand. The company strengthened liquidity through a March 2026 private placement (approximately $85.0 million gross) and January 2026 at‑the‑market sales ($5.1 million gross). Cash, cash equivalents and marketable securities totaled $137.9 million at June 30, 2026, which management expects to fund operations for at least 12 months.
Korro advanced lead programs KRRO‑121 for hyperammonemia, expected to enter first‑in‑human trials in the second half of 2026, and KRRO‑111 for alpha‑1 antitrypsin deficiency, after terminating the Phase 1/2a REWRITE trial for prior candidate KRRO‑110 in early 2026.
Korro Bio, Inc. entered into an exchange agreement with entities affiliated with Venrock Healthcare Capital Partners. Venrock will surrender 1,000,000 common shares to Korro for no consideration, and Korro will issue pre-funded warrants for 1,000,000 common shares with a $0.001 exercise price and no expiration. The warrants are immediately exercisable but include a 9.99% beneficial ownership cap. After the exchange, Korro will have 13,725,646 common shares outstanding and pre-funded warrants for 4,148,836 shares.
For the quarter ended June 30, 2026, Korro reported cash, cash equivalents and marketable securities of $137.9 million, supporting a projected cash runway into the second half of 2028. Research and development expenses were $13.6 million and general and administrative expenses were $6.5 million, contributing to a net loss of $18.9 million compared with $25.8 million a year earlier. Collaboration revenue was $0 versus $1.5 million in the prior-year quarter following a 12‑month pause of the Novo Nordisk collaboration.
Korro Bio, Inc. reports that President and CEO Ram Aiyar sold 5,802 shares of common stock on August 4, 2026 at a weighted-average price of $10.844 per share in mandatory sales solely to cover tax withholding on vested RSUs under its 2023 Stock Option and Incentive Plan. Following these transactions, he holds 69,046 shares directly, including 20,000 unvested RSUs scheduled to vest on February 1, 2027 subject to a continuous Service Relationship, and 4,613 shares are held indirectly through The Ram Aiyar Irrevocable Trust.
Atlas Venture funds filed Amendment No. 1 to Schedule 13D reporting their combined ownership in Korro Bio, Inc. common stock. Collectively, the reporting entities beneficially own 852,861 shares of common stock, representing an estimated 5.9% of Korro Bio’s outstanding shares.
Atlas Venture Fund XI, L.P. and its related general partners report 706,556 shares, or 4.9% of the outstanding common stock, with shared voting and dispositive power. Atlas Venture Opportunity Fund II, L.P. and its related general partners report 146,305 shares, or 1.0%. Percentages are based on 14,422,571 shares outstanding as of May 4, 2026. The funds are under common control and state they may be deemed a group, but they expressly disclaim group membership. Recent transactions within the past sixty days are listed in an exhibit.
KRRO shareholder Ram Aiyar filed a notice of proposed sale of 5,802 common shares through Fidelity Brokerage Services LLC, with an aggregate market value of $662,917.47, expected around August 4, 2026 on NASDAQ. The shares are scheduled to come from restricted stock vesting granted as compensation by the issuer on August 3, 2026. KRRO reports 14,422,571 common shares outstanding. In the prior three months, Aiyar sold 15,152 common shares on May 29, 2026 for gross proceeds of $196,675.99.