--- title: "Cerebras CTO and COO sold $228 million under prearranged plans before the lock-up expired November 9" description: "The filings everyone watches cannot show the selling: 13Fs land blind, and only SEC forms reveal two executives took about $228 million under prearranged plans before the door opened. Thursday's print settles margin, not demand, and a short seller's wafer-lifespan claim sits under the gross margin line." publisher: "The Inference" section: "Chips" published: 2026-11-11T14:16:26.433Z modified: 2026-11-11T14:16:26.433Z canonical: https://theinference.org/article/cerebras-cto-and-coo-sold-228-million-under-prearranged-plans-before-the-lock-up-expired-november-9 language: en keywords: "Cerebras, Insider Selling, Earnings, Lock Up Expiration, Semiconductors" --- # Cerebras CTO and COO sold $228 million under prearranged plans before the lock-up expired November 9 > The filings everyone watches cannot show the selling: 13Fs land blind, and only SEC forms reveal two executives took about $228 million under prearranged plans before the door opened. Thursday's print settles margin, not demand, and a short seller's wafer-lifespan claim sits under the gross margin line. At 6:00 a.m [1]. ET [1] on Monday, November 9, the last door on Cerebras' IPO opened. The main lock-up on the chipmaker's shares expired 180 days after its May 13 prospectus, freeing holders of roughly 71.4% of Class A stock from contractual restrictions, three days before the company reports Q3 results on November 12 [1]. The market shrugged: the stock closed Monday at $96.70, up nearly 8% [3]. The headline number here is $228 million: [the two big prearranged sales](https://theinference.org/article/insiders-sold-277-million-of-cerebras-stock-before-the-main-lockup-opens) by the chief technology officer and the chief operating officer, recorded before the lock-up ended [1]. Adding a tax-related sale and a smaller plan sale brings the disclosed total to about $244 million [1]. ## The money that is already gone [Cerebras](https://theinference.org/markets/companies/cerebras-systems) listed in May at $185 a share [1]. It closed 49.3% below that price on Monday morning, and options pricing implies a move of about 12% around Thursday's report, with implied volatility above 100% [1][3]. Up to about 171.1 million shares can become eligible across the lock-up schedule, including up to 15 million held by directors and officers [1]. ## The filings everyone watches cannot show the selling Here is the complication: the 13Fs funds must file by November 16 show holdings as of September 30, six weeks before the door opened, and the prospectus' alternative lock-up trigger, the second trading day after earnings, also lands on November 16 [1]. The only records that catch the selling are [Form 144s and Form 4s](https://financefeeds.com/cbrs-stock-cerebras-lock-up-expires-ahead-of-nov-12-q3-results/), and they show two executives out early [1]. CTO [Sean Lie](https://theinference.org/markets/people/sean-lie) sold 710,247 shares for about $147.63 million on August 20 and 60,000 more for about $6.5 million on October 27; COO [Dhiraj Mallick](https://theinference.org/markets/people/dhiraj-mallick) sold 396,000 shares for about $80.8 million on September 29, all under prearranged 10b5-1 plans [1]. Mallick's remaining $8.64 million sale in August was not discretionary: his Form 4 identifies it as a sell-to-cover transaction to satisfy tax withholding [1]. *Chart: **Cerebras executives sold about $244 million of stock before the lock-up ended** Bar chart of disclosed Cerebras insider sales from August to October 2026, led by CTO Sean Lie's $147.6 million August 20 sale, with the Mallick August 18 sale marked as sell-to-cover.* *Gross proceeds per SEC Form 144 and Form 4 filings, in millions of US dollars, August to October 2026. Total about $244 million. Source: FinanceFeeds, November 9, 2026 [1]. [1]* ## Thursday settles margin, not demand The guide is the tell. [Management projects core revenue of $214 to $216 million](https://finance.yahoo.com/markets/stocks/articles/cerebras-q3-earnings-preview-expect-114201820.html) against $209.9 million in Q2, essentially flat, with core gross margin guided down to 38 to 40% and core operating margin worsening to negative 25% to negative 23% [1][3][4]. Against that sits $25.4 billion of remaining performance obligations at June 30, mostly [OpenAI](https://theinference.org/markets/companies/openai)'s commitment to buy 750 megawatts with an option for 1.25 gigawatts more [1]. That is about 29 years of the full-year revenue guide; it promises megawatts, not next quarter [1]. *Chart: **Core gross margin has slid for three straight quarters** Column chart showing Cerebras core gross margin falling from 46.5% in Q1 2026 to 40.6% in Q2 to a guided 38-40% range in Q3.* *Cerebras core (non-GAAP) gross margin by quarter, percent. Q3 shown as the low end of the 38-40% guided range, which is management guidance, an estimate. Sources: TIKR, November 9, 2026 [2]; Yahoo Finance UK (Zacks), November 10, 2026 [4]. [2][4]* ## The fight under the margin [Short seller Culper Research alleged](https://theinference.org/article/cerebras-s-customer-pays-3-to-5x-for-2-000-tokens-a-second-culper-research-says-the-wafers-fail-in-2-years) on October 28 that the wafers last 1.5 to 2.5 years, that Cerebras uses a third-party connector called PariPoser, and that the company runs continuous dummy operations to guard against temperature swings that could damage its wafers [1]. CEO Andrew Feldman answered that fewer than 0.5% of deployed CS-3 wafers have been decommissioned, that [TSMC](https://theinference.org/markets/companies/tsmc) qualifies the wafer for 10 years at 105 degrees Celsius, and that no PariPoser ever shipped; the useful-life estimate moved from 1-3 years to 3-5 years as assets shifted to the cloud fleet [1]. Feldman discloses he is long the stock [1]. The bulls have not flinched. [Wedbush kept Outperform but cut its target to $190 from $290](https://uk.finance.yahoo.com/news/buy-sell-hold-cerebras-systems-193300221.html); the consensus target sits near $275 against a $96 stock, with Altimeter, Tiger Global and ARK among the June 30 holders now 59% underwater [2][3]. ## What to watch Watch the Form 144 tape, the first place any big unlocked seller shows up, then February's 13Fs, which show who still held at December 31 [1]. And watch the gross margin line on Thursday: if it holds the guide, the overhang is noise; if it slides, Culper's number is eating the economics. ## Takeaway Form 144s, not 13Fs, caught Cerebras' $228 million prearranged insider selling; Thursday's Q3 gross margin decides whether the short seller's wafer claim is real. ## Sources 1. [FinanceFeeds, CBRS Stock: Cerebras Lock-Up Expires Ahead of Nov. 12 Q3 Results, 9 November 2026](https://financefeeds.com/cbrs-stock-cerebras-lock-up-expires-ahead-of-nov-12-q3-results/) 2. [TIKR, Cathie Wood and 73 Other Funds Bought Chip Stocks. Cerebras Is Down 59% Since. Time to Buy?, 9 November 2026](https://www.tikr.com/blog/cathie-wood-funds-bought-chip-stocks-cerebras-down-51-time-to-buy) 3. [Yahoo Finance (GuruFocus), Cerebras Q3 Earnings Preview: What To Expect From Upcoming Report, 10 November 2026](https://finance.yahoo.com/markets/stocks/articles/cerebras-q3-earnings-preview-expect-114201820.html) 4. [Yahoo Finance UK (Zacks), Should You Buy, Sell, or Hold Cerebras Systems Stock Before Q3 Earnings?, 10 November 2026](https://uk.finance.yahoo.com/news/buy-sell-hold-cerebras-systems-193300221.html) --- Cerebras CTO and COO sold $228 million under prearranged plans before the lock-up expired November 9 — The Inference. Canonical: https://theinference.org/article/cerebras-cto-and-coo-sold-228-million-under-prearranged-plans-before-the-lock-up-expired-november-9