FMR LLC and Abigail P. Johnson filed Amendment No. 2 to a Schedule 13G with the SEC on November 4, 2026, disclosing beneficial ownership of Class A Common Stock of Cerebras Systems Inc. as of September 30, 2026.

Key Highlights

  • Aggregate beneficial ownership: FMR LLC and Abigail P. Johnson each reported beneficial ownership of 30,337,839.44 shares of Cerebras Systems Class A Common Stock.
  • Percent of class: The reported holdings represent 17.8% of the outstanding Class A Common Stock.
  • Sole voting power (FMR LLC): FMR LLC reported sole voting power over 29,758,206.61 shares; Abigail P. Johnson reported sole voting power of 0.00 shares.
  • Class B conversion component: 19,474,786 of the reported shares are attributable to direct ownership of Class B Common Stock, convertible into Class A Common Stock at a 1:1 exchange rate, representing 25.0631% of outstanding Class B Common Stock.
  • Post-conversion ownership: Assuming conversion of all outstanding Class B shares into Class A shares, the filing states the 30,337,839.44 shares would represent 17.7979% of outstanding Class A Common Stock.
  • Event date: The date of the event requiring this filing is September 30, 2026.

FMR LLC and Abigail P. Johnson Disclose Large Ownership Position in Cerebras Systems Class A Shares

According to the filing, FMR LLC, a Delaware-organized holding company headquartered at 245 Summer Street, Boston, Massachusetts 02210, and Abigail P. Johnson, a U.S. citizen, each reported aggregate beneficial ownership of 30,337,839.44 shares of Class A Common Stock of Cerebras Systems Inc. (CUSIP 15675D103), representing 17.8% of that class as of September 30, 2026. The filing is Amendment No. 2 to a previously filed Schedule 13G and was signed on November 4, 2026.

The filing discloses that 19,474,786 of those shares are included because investment companies advised by Fidelity Management & Research Company LLC, Fidelity Institutional Asset Management Trust Company, Fidelity Management Trust Company, and Fidelity Diversifying Solutions LLC, described as an indirect wholly-owned subsidiary of FMR LLC, directly own 19,474,786 shares of Class B Common Stock. Those Class B shares are convertible into Class A shares at the holder's election on a 1:1 basis and, according to the filing, represent 25.0631% of the outstanding Class B Common Stock. The remaining portion of the reported beneficial ownership consists of direct Class A holdings.

FMR LLC reported sole dispositive power over all 30,337,839.44 shares and sole voting power over 29,758,206.61 shares, with shared voting and shared dispositive power each reported as 0.00. Abigail P. Johnson reported sole dispositive power over the same 30,337,839.44 shares and sole voting power of 0.00. The filing certifies that the securities "were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer."

What Was Disclosed

FMR LLC and Abigail P. Johnson filed Amendment No. 2 to Schedule 13G disclosing combined beneficial ownership of 30,337,839.44 Cerebras Systems Class A shares, equal to 17.8% of that class, as of September 30, 2026, including shares attributable to convertible Class B holdings.