Welcome to our dedicated page for Magnite SEC filings (Ticker: MGNI), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Magnite, Inc. filings document the regulatory record of an operating ad technology company focused on sell-side programmatic advertising. Form 8-K reports furnish quarterly and annual results, including revenue, contribution ex-TAC, CTV and DV+ metrics, adjusted EBITDA, cash flow measures, outlook commentary and stock buyback disclosures.
The company’s proxy materials cover annual meeting matters, director elections, executive compensation and stockholder voting procedures. Other filings document executive transitions, material agreements, Regulation FD disclosures and risk-factor updates, including litigation and competitive risks tied to the digital advertising ecosystem.
Magnite, Inc. (MGNI) – Form 4 insider activity
Chief Financial Officer David Day reported a same-day option exercise and share sale executed on 18 June 2025 under a pre-arranged Rule 10b5-1 trading plan adopted 13 March 2025.
- Option exercise: 38,146 employee stock options exercised at an exercise price of $4.92 (grant dated 20 Feb 2019, fully vested).
- Share sale: The exact 38,146 shares were disposed of on the open market at an average price of $18.95.
- Gross transaction value: Approximately $723k in proceeds (38,146 × $18.95) versus a cash outlay of roughly $188k for the exercise, implying a pre-tax gain of about $535k.
- Post-transaction ownership: Day retains 443,528 Magnite common shares held directly, indicating continued exposure to the company’s equity despite the sale.
There were no derivative holdings remaining from the exercised option grant, and no new option awards were reported. Because the activity was executed under an established 10b5-1 plan and represents less than 8% of Day’s reported ownership, the filing appears routine. Investors should nonetheless note the CFO’s decision to monetize a portion of his stake at a price materially above the option strike, potentially signalling confidence in capturing value or addressing personal liquidity needs rather than a fundamental view of Magnite’s prospects.
Magnite, Inc. (MGNI) filed a Form 4 disclosing transactions by President of Operations Katie Seitz Evans. On 06/16/2025 she exercised 20,000 stock options at an exercise price of $3.61 per share, immediately followed by a sale of the same 20,000 common shares at $18.50 per share. The exercise originated from an option grant dated 02/26/2018 that fully vested by February 2022.
Following the transactions, Evans’ direct common-stock holdings decreased by 20,000 shares to 442,788. She continues to hold 16,137 vested options with a $3.61 strike price expiring 02/26/2028.
The filing notes that both the exercise and sale were conducted under a Rule 10b5-1 trading plan adopted on 03/06/2025, providing advance notice and reducing interpretative risk around timing. No other derivatives or indirect holdings were reported.
Financial magnitude: gross sale proceeds approximate $370,000 versus an exercise cost of about $72,200, implying a before-tax gain of roughly $298,000. Despite the sale, Evans maintains a sizeable equity stake, representing continued alignment with shareholder interests.
Magnite, Inc. (MGNI) – Form 4 insider transaction
Chief Legal Officer Aaron Saltz reported the sale of 16,788 shares of common stock on 16-Jun-2025 at $17.50 per share. The transaction was executed pursuant to a Rule 10b5-1 trading plan adopted on 14-Mar-2025, indicating it was pre-scheduled. Following the sale, Saltz continues to hold 279,388 shares directly.
No derivative securities were transacted, and the filing does not disclose additional purchases, options exercises, or dispositions. The filing was signed on 18-Jun-2025 and reflects a single-person submission.
Key take-aways for investors
- Insider is reducing—not increasing—equity exposure, though holdings remain sizable.
- The Rule 10b5-1 plan mitigates concerns of opportunistic selling but does not eliminate potential negative market signaling.
- The transaction size represents ~6.0% of Saltz’s post-sale ownership (16,788 ÷ (279,388 + 16,788)).
Magnite, Inc. (MGNI) – Form 144 filing overview: The notice discloses a proposed sale of 137,007 common shares through Morgan Stanley Smith Barney LLC, valued at $2.57 million based on prevailing market prices. The filing targets an approximate sale date of 18 June 2025 on the NASDAQ exchange. With 141,110,559 shares outstanding, the transaction represents roughly 0.10 % of total shares, indicating a modest disposition relative to the company’s float.
The seller acquired the stock via (1) option exercise on 28 July 2020 (112,087 shares, cash payment) and (2) restricted-stock grants on 1 April 2020 (11,177 shares) and 12 June 2024 (13,743 shares). No sales have occurred in the past three months, and the preparer affirms the absence of undisclosed material adverse information. The filing does not identify the seller by name but confirms the relationship is that of an insider covered by Rule 144 and potentially a Rule 10b5-1 trading plan.
Key takeaways for investors:
- The proposed sale is relatively small in percentage terms and unlikely to create significant market overhang.
- Use of Form 144 indicates the seller is observing SEC resale restrictions, which generally mitigates regulatory risk.
- Lack of past-quarter sales suggests the move may be routine portfolio diversification or liquidity, rather than a large liquidation.
No financial performance metrics, earnings data, or operational updates are included; the filing solely concerns share resale.
Magnite, Inc. (MGNI) Form 4 filing: CEO & Director Michael G. Barrett disclosed two open-market sales executed under a Rule 10b5-1 trading plan adopted on 03/12/2025.
- 06/16/2025: 45,000 shares of common stock sold at a $17.76 weighted-average price (range $17.30-$18.00).
- 06/18/2025: 30,000 shares sold at $19.00.
Total shares sold: 75,000. Following the transactions, Barrett owns 656,708 shares directly.
The Form notes that detailed price breakdowns are available upon SEC request. No derivative security activity was reported.
The sales reduce Barrett’s direct holdings by roughly 10% (derived from reported numbers) yet maintain a sizable remaining stake, suggesting continued alignment. Because sales were pre-planned, they may be viewed as routine rather than signaling strategic shifts. No other material events or company operational data were included in this filing.