MAGNITE, INC. (MGNI) stock intrinsic value fair value estimate & owner earnings analysis

Magnite runs an advertising exchange that sits between publishers (the sellers of ad space) and advertisers (the buyers). It earns a fee on advertising spend that flows through its platform. In 2025 revenue was $714 million: connected-TV (streaming) 48%, mobile 37%, desktop 15%. About 90% of revenue is recorded net of what is passed on to publishers. Three-quarters of revenue is from U.S. sellers. How we measure earnings. We start from operating cash flow, then remove the swing from working capital, subtract stock-based pay as a real cost, and subtract only the maintenance portion of capital spending. Magnite's receivables and payables are very large relative to revenue because it collects from advertisers and pays publishers. Payables have grown faster than receivables every year since 2021, which has flattered operating cash flow by $28 million to $77 million a year. We strip that out. Stock-based pay of about $77 million a year is roughly 1.5 times the earnings we are left with, which is why the result is small. Owner earnings per share were $0.34 (2021), $0.40 (2022), $0.24 (2023), $0.27 (2024) and $0.33 (2025). We use the middle of those five years, $0.33 a share (about $51 million), as the earning power today. Earlier years are excluded because the 2020 merger with Telaria changed the business and 2019 and 2020 were loss years for the pre-merger company. 2025 capital spending jumped to $84 million from $47 million; the filing does not say why, and we treated it as a normal cost of staying in business. Growth. Owner earnings grew about 30% in 2025 (about 24% per share), largely because 2024 was depressed by working-capital and spending timing. We start the base case at zero growth, below that. Revenue has grown 7% to 8% a year for three years, led by streaming, and the first half of 2026 revenue was up about 8.5%. But this growth depends on ad spending and the platform's share of it, neither of which is locked in by a contract or backlog, and stock pay and capital spending have absorbed most of the gains so far. We credit none of it. Base case, $3.20 a share. Earnings stay at $0.33 a share for 15 years and then stop. The evidence for persistence is that revenue has grown in every year since 2020 and publishers keep routing their inventory through the platform; we do not credit any longer life because that record is only about six years and the company says fee pressure is building in streaming, where most sales are reserve auctions that carry lower fees. Bear case, $1.10 a share. Earnings fall to $0.20 a share (below the 2023 low of $0.24) and last seven years. This assumes streaming publishers, who the filing says hold the bargaining power, force further fee cuts, and that Google, which Magnite says is both a partner and a competitor and a significant source of revenue, retaliates after the lawsuit Magnite filed against it in September 2025. Debt adds to the downside: $565 million of term loan and convertible notes were outstanding at the end of 2025 against $553 million of cash. The convertible notes matured in March 2026 and the company planned to repay them from cash. We do not subtract debt from any case, since owner earnings are already after interest. Bull case, $5.90 a share. Earnings return to the 2022 level of $0.40, grow 6% a year for five years (streaming revenue has grown 9% to 13% a year for the last two years) and then hold flat until year 20. Any damages from the Google lawsuit are excluded because the company itself says it may receive none. The main reasons these estimates could be too low: the working-capital cushion we removed proves to be permanent, which would raise earnings by several cents a share; the 2025 spending spike proves temporary; or streaming take rates hold. The main reasons they could be too high: fee concessions in streaming, Google retaliation, or a reversal in working capital that would hurt cash flow. Magnite's revenue is partly reported gross of publisher payments (10% in 2025, down from 18% in 2023), so headline revenue growth understates growth in what the company keeps.