Cerebras Systems CTO Sean Lie Disposes $11.24M in Class A Shares Under 10b5-1 Plan

Executive Summary

On September 4, 2026, Sean Lie, Chief Technology Officer of Cerebras Systems Inc. ($CBRS), engaged in a multi-step transaction involving the exercise of stock options, share conversions, a charitable gift, and an open market sale under a pre-established Rule 10b5-1 trading plan.

Transaction Details

1. Option Exercise & Conversion:
   • Exercised options to acquire 46,141 shares of Class B Common Stock at an exercise price of $5.48 per share.
   • Converted 46,141 Class B shares to Class A Common Stock on a 1-for-1 basis.
2. Charitable Contribution (Code G):
   • Transferred 16,038 shares of Class A Common Stock to a 501(c)(3) donor-advised fund ($0 consideration).
3. Open Market Sale (Code S):
   • Sold 53,460 shares of Class A Common Stock at a weighted average price of $210.16 (ranging between $210.00 and $210.45) for gross proceeds of approximately $11,235,153.60.
   • The sale was executed pursuant to a Rule 10b5-1 trading plan adopted on May 20, 2026.

Ownership Post-Transaction

• Direct Class A Common Stock: 345,569 shares
• Direct Class B Common Stock: 7,582,992 shares
• Indirect Class B Common Stock (By Spouse): 180,600 shares
• Remaining Derivative Stock Options: 289,021 options

Analysis

The transaction represents high-value liquidity generation ($11.2M) via a scheduled Rule 10b5-1 trading plan following option exercise. The insider retains substantial equity exposure through over 7.5 million Class B super-voting shares.