Monolithic Power Systems, Inc.
Orin's own judgment of how firmly the evidence points one way — not the chance the price goes up.
Monolithic Power's AI-driven revenue acceleration is exceptional—Q2 2026 revenue reached $980.6M with 47.6% YoY growth and EPS beat estimates by 10.7%—but the stock at $1,386.29 trades at 84.5x trailing P/E, a 72% premium to the peer median of 49.1x, and 20.8x P/S versus a peer median of 4.9x, pricing in years of near-flawless execution.
Persistent insider selling—334 dispositions and zero acquisitions over 24 months for net -$633K shares and -$665M in value, including CEO Michael Hsing's sale of 30,000 shares on 28 Sep—combined with a slightly negative smart-money score of -0.02 as of Q2 2026 tempers enthusiasm. The growth is real and technicals are constructive (above both 50-day and 200-day MAs with positive MACD histogram of 7.71), but the valuation premium and insider signal make this a hold rather than a buy.
What could go wrong
- Valuation compression. At 84.5x P/E and 20.8x P/S—72% and 327% above peer medians respectively—any deceleration in revenue growth or margin pressure could trigger a sharp multiple contraction.
- Persistent insider selling. Over 24 months, insiders executed 334 dispositions with zero acquisitions, netting -$633K shares and -$665M in value; CEO Michael Hsing sold 30,000 shares on 28 Sep at prices from $1,323 to $1,357.
- Operating margin compression. Operating margin declined from 29.4% in FY2022 to 26.1% in FY2025 despite revenue growth from $1.79B to $2.79B, suggesting cost pressures are scaling with growth.
- AI demand cyclicality. Revenue growth of 47.6% YoY in Q2 2026 is heavily tied to AI/data-center demand; any slowdown in AI capex could materially impact the growth trajectory the valuation demands.
What would change my mind
Where this comes from: Q2 2026 results · earnings vs estimates, 30 Jul · peer comparison, 9 Oct · insider trades, last 24 months. Orin's read on MPWR; not advice.
How has the share price moved?
Up 9.7% over twelve months, from $1,105.05 on 27 Oct 2025 to $1,211.89 at the Tue 27 Oct 2026 close. Its highest close in that time was $1,689.89 on 3 Jun 2026; the last close is 28.3% below it.
- Green line: the closing price each trading day.
- Grey line: the average closing price over the last 50 trading days.
- Dashed amber line: the same over the last 200 trading days — a slower, smoother line.
- Bars along the bottom: shares traded each day — green when it closed higher than the day before, rose when lower (the most, 5.6M, on 19 Dec 2025).
- Flags: the company's filings, on the day they were made (a 10-Q is the quarterly report and a 10-K the annual report; an 8-K reports a major event).
- Rose flags: large share sales by the company's own officers and directors, from the Form 4 each one files after trading.
On file
All MPWR filingsLargest holders · 13F Q2 2026
Money flow| Filer | Position | Of fund |
|---|---|---|
| BlackRock | $7.7B | 0.1% |
| FMR | $7.2B | 0.3% |
| Vanguard Capital Management | $4.3B | 0.1% |
| Vanguard Portfolio Management | $3.5B | 0.2% |
| Invesco | $3.2B | 0.3% |
| State Street | $3.2B | 0.1% |
| Geode Capital Management | $1.6B | 0.1% |
| T. Rowe Price Associates | $1.4B | 0.1% |
| Franklin Resources | $1.1B | 0.2% |
| Goldman Sachs Group | $1.1B | 0.1% |
115 of the 815 filers we track · quarter ended Q2 2026 · positions, not flows
Insiders, last 24 months: 379 Form 4 filings; open-market trades net −$665.0M. Of the 50 on hand, 0 were open-market purchases and 43 sales — the rest are grants, option exercises and tax withholding.
Ask Orin about MPWR
Orin answers questions about MPWR from its filings, transcripts and numbers — with the source behind every claim. Your own desk starts with 3 free days, card required.
Start 3 free days →How is it priced, against its own past and its sector?
Priced at 73.9× its last 12 months of profit (Tue 27 Oct close); the typical Technology company on the NASDAQ is at 46.1×.
| Measure | Now | Its usual | Sector |
|---|---|---|---|
| P/E | 73.9× | — | 46.1× |
| P/S | 18.2×above usual | 15.6× | — |
| EV/EBITDA | 56.1×above usual | 51.9× | — |
| P/B | 15.3×above usual | 12.3× | — |
- P/E: no usual level — it ran from 16.1× to 93.4× over its last 5 fiscal years, so a middle value says little.
- "Its usual" is the middle of its own last 5 fiscal years.
P/E: the share price divided by one year of profit per share — roughly how many years of today's profit the price pays for. A company that loses money has no P/E.
P/S: the company's total market value divided by one year of revenue. Used when there is no profit to measure.
EV/EBITDA: the price of the whole company (its shares plus its debt, minus its cash) divided by one year of operating profit before interest, tax and write-downs.
P/B: the share price divided by the book value per share — what the company owns minus what it owes, as its accounts record it. When book value is tiny, P/B swings wildly and says little.
What do the analysts who cover it publish?
The analysts' average 12-month price target is $1,824 (from $1,500 to $2,100) — 51% above the Tue 27 Oct close price. That is their published opinion, not Orin's.
$1,824
$1,500 – $2,100 · +51% against the last close
- 11 buy or overweight
- 1 hold
- 0 underweight or sell
Price target: the share price an analyst publishes for about 12 months ahead. It is the opinion of the firm that wrote it; the average is across the firms that cover the company.
Overweight / underweight: analysts' rating words: overweight means the firm expects the stock to do better than the others it covers, underweight worse. Their words, not Orin's.
How is it priced next to the companies it is compared to?
Priced at 73.9× its last 12 months of profit; the middle P/E of the 6 companies it is compared to that made a profit is 48.9×.
| Company | Market value | P/E | EV/EBITDA | Gross margin | Net margin | ROE |
|---|---|---|---|---|---|---|
| MPWRMonolithic Power Systems, Inc. | $60B | 73.9× | 56.1× | 55.2% | 24.4% | 22% |
| ADIAnalog Devices, Inc. | $206B | 50.2× | 30.3× | 65.8% | 29.8% | 12% |
| AOSLAlpha and Omega Semiconductor Limited | $560M | lost money | n/m | 22.6% | −6.9% | −6% |
| DIODDiodes Incorporated | $3B | 27.1× | 12.1× | 33.3% | 6.5% | 6% |
| ONON Semiconductor Corporation | $31B | 49.8× | 20.5× | 37.4% | 10.2% | 8% |
| POWIPower Integrations, Inc. | $2B | 48.0× | 30.2× | 53.9% | 9.8% | 7% |
| STMSTMicroelectronics N.V. | $43B | 91.8× | 19.2× | 34.3% | 3.5% | 3% |
| TXNTexas Instruments Incorporated | $282B | 40.0× | 26.6× | 60.2% | 34.3% | 41% |
- AOSL: lost money over the last 12 months, so no P/E.
- AOSL: EV/EBITDA is not meaningful (n/m) — its cash exceeds its market value plus debt, or the business lost money before depreciation.
- The list of companies is the data vendor's choice, so it can include a company a person would not have picked.
Market value: the share price times the number of shares — what the whole company is priced at.
P/E: the share price divided by one year of profit per share — roughly how many years of today's profit the price pays for. A company that loses money has no P/E.
EV/EBITDA: the price of the whole company (its shares plus its debt, minus its cash) divided by one year of operating profit before interest, tax and write-downs.
Gross margin: the share of each $1 of sales left after the direct cost of making what was sold.
Net margin: the share of each $1 of sales kept as profit after every cost. Below zero, the company lost money.
ROE: return on equity: one year of profit as a share of the shareholders' money in the business (its book value).
Is it priced high or low compared with its own past?
Priced at 73.9× its last 12 months of profit (Tue 27 Oct close). It has no full fiscal year on file since its history starts, so there is nothing of its own to compare with.
- Now73.9×
P/E: the share price divided by one year of profit per share — roughly how many years of today's profit the price pays for. A company that loses money has no P/E.
Fiscal year (FY): the company's own 12-month accounting year, which need not match the calendar year.
How has its sector been priced?
Technology companies on the NASDAQ were priced at a typical 46.1× their yearly profit (Tue 27 Oct close).
- Now46.1×
- Each year is the middle of that calendar year's daily sector P/E; "Now" is the Tue 27 Oct close figure, the same one in the table above.
Sector P/E: the middle P/E of the companies in the same sector on the same stock exchange, as the data vendor works it out each day.
What does a cash-flow model say a share is worth?
A standard cash-flow model puts it at $238 a share — 80% below the $1,199.95 price it was computed against (27 Oct).
| Model | Value a share | Against the price then |
|---|---|---|
| Standard | $238 | 80% below $1,199.95 |
| Levered | $367 | 69% below $1,199.95 |
Discounted cash flow: a model's estimate of what the company is worth today, from the cash it is forecast to make in future years. Small changes in the forecast move it a lot, and it says little about a company that loses money.
Standard / levered: two versions of the cash-flow model: the standard one counts the cash before the company pays its lenders, the levered one after.