Bain Capital Life Sciences Opportunities IV, L.P. filed a Schedule 13G with the SEC on October 29, 2026, reporting beneficial ownership of Common Shares of ADC Therapeutics SA (NYSE:ADCT) as of October 22, 2026.

Key Highlights

  • Beneficial ownership reported: 14,825,625 Common Shares, representing 9.99% of ADC Therapeutics SA's outstanding Common Shares as of October 22, 2026.
  • Direct share holdings: The Reporting Person held 7,000,000 Common Shares directly as of October 22, 2026.
  • Pre-funded warrants: The Reporting Person also held pre-funded warrants to purchase up to 22,703,927 Common Shares, subject to a Beneficial Ownership Blocker capping ownership at 9.99%.
  • No sole voting or dispositive power: The filing reports 0 shares with sole voting or sole dispositive power; all 14,825,625 shares are held with shared voting and shared dispositive power.
  • Shares outstanding basis: The 9.99% figure is based on 127,667,695 Common Shares outstanding as of August 3, 2026, plus 12,911,347 shares from a private placement on October 22, 2026, and 7,825,625 shares issuable upon partial exercise of pre-funded warrants.
  • Reporting entity: Bain Capital Life Sciences Investors, LLC is identified as the manager of the chain of entities that controls the Reporting Person, and may be deemed to share voting and dispositive power over the reported shares.

Bain Capital Life Sciences Entities Disclose 9.99% Stake in ADC Therapeutics After October 2026 Private Placement

According to the Schedule 13G filed October 29, 2026, Bain Capital Life Sciences Opportunities IV, L.P., a Delaware limited partnership, reported beneficial ownership of 14,825,625 Common Shares of ADC Therapeutics SA, par value CHF 0.08 per share (NYSE:ADCT). The filing states that the Reporting Person held 7,000,000 Common Shares outright and pre-funded warrants to purchase up to 22,703,927 additional Common Shares as of October 22, 2026, the date of the triggering event.

The filing explains that the Reporting Person "is prohibited from exercising the pre-funded warrants if, as a result of such exercise, the Reporting Person would beneficially own more than 9.99% of the total number of Common Shares then issued and outstanding immediately after giving effect to the exercise." This Beneficial Ownership Blocker limits the reported beneficial ownership to 14,825,625 Common Shares, or 9.99% of the class. The share base used to calculate that percentage combines 127,667,695 shares outstanding as of August 3, 2026, as reported in ADC Therapeutics' Form 10-Q filed August 13, 2026, with 12,911,347 shares sold in a private placement on October 22, 2026, as reported in the company's Form 8-K filed October 13, 2026, and 7,825,625 shares issuable upon partial warrant exercise.

The filing identifies Bain Capital Life Sciences Investors, LLC ("BCLSI") as the manager of Bain Capital Life Sciences IV General Partner, LLC, which is the general partner of Bain Capital Life Sciences Fund IV, L.P., which is the sole member of Bain Capital Life Sciences Opportunities IV GP, LLC, which in turn is the general partner of the Reporting Person. As a result, the filing states, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Reporting Person. The principal business address for all Bain Capital Life Sciences Entities is listed as 200 Clarendon Street, Boston, Massachusetts 02116. The filing was signed by Andrew Hack, Partner of Bain Capital Life Sciences Investors, LLC.

What Was Disclosed

Bain Capital Life Sciences Opportunities IV, L.P. disclosed a 9.99% beneficial ownership position in ADC Therapeutics SA Common Shares via Schedule 13G, reflecting direct share holdings and partial pre-funded warrant coverage as of October 22, 2026, constrained by a contractual Beneficial Ownership Blocker.