Marathon Petroleum Corp (MPC) is overvalued and Sunoco LP (SUN) is undervalued.
Against our estimates of intrinsic value, SUN trades at the wider discount: a margin of safety of +21%, against -37% for MPC.
Values as of the 22 Sept 2026 close.
Discounting its cash flows at 7.8% (average of 3 methods) values the shares at $284.85; the price of $389.68 is 37% above that value, and 79% of that value comes from beyond year five.
Leak Score 62/100 on 10 of 12 signals
Discounting its cash flows at 6.6% (average of 3 methods) values the shares at $92.66; the price of $73.12 is 21% below that value, and 85% of that value comes from beyond year five.
Leak Score 56/100 on 2 of 12 signals
| Metric | MPC | SUN |
|---|---|---|
| Verdict | Overvalued | Undervalued |
| Price | $389.68 | $73.12 |
| Intrinsic value | $284.85 | $92.66 |
| Margin of safety | -37% | +21% |
| Leak Score | 62/100 (10/12) | 56/100 (2/12) |
| Market cap | $109.4B | $15.0B |
| Revenue growth, 5 years | 13.9% | 18.7% |
| Operating margin | 8.4% | 4.9% |
| Net margin | 5.6% | 1.6% |
| Return on equity | 47.9% | 14.5% |
| Debt to equity | 1.80 | 1.78 |
| P/E | 13.4x | 16.0x |
| Forward P/E | 8.5x | 8.0x |
| P/B | 5.8x | 1.5x |
| Dividend yield | 1.1% | 5.5% |