The unanimous accumulation by four active asset managers — particularly the doubling of stakes by Assenagon and Td Waterhouse — suggests conviction in MPC's refining margin outlook or capital return trajectory. However, 13F data reflects Q3-end positions filed with a 45-day lag; monitor for any subsequent insider trading or earnings guidance that could confirm or contradict this thesis.
Executive Summary
Four asset managers significantly increased their MPC positions in Q3 2026, with two funds doubling their stakes. Total institutional buying reached $87.0M in new capital deployed, with zero selling among tracked funds. This cluster suggests a shared positive view on Marathon Petroleum's refining and mid-cycle earnings potential, though 13F data is stale by 45+ days.
Key Financial Metrics
Institutional Positions
Net institutional flow: $87.0M
▲ Buyers (4)
| Institution | Action | Change | Position Value | Value Δ |
|---|---|---|---|---|
| Assenagon Asset Management | DOUBLED | +206.1% | $81.8M | $64.5M |
| Td Waterhouse Canada | DOUBLED | +200.3% | $19.4M | $15.3M |
| Farther Finance Advisors | ADD | +34.8% | $8.2M | $4.3M |
| Mather Group | ADD | +72.7% | $4.7M | $2.9M |
Key Facts
- 4 tracked institutions added $87.0M in net new MPC positions during Q3 2026
- Assenagon Asset Management doubled its stake (+206.1%), adding $64.5M to reach $81.8M
- Td Waterhouse Canada doubled its position (+200.3%), adding $15.3M to reach $19.4M
- Farther Finance Advisors added 34.8% (+$4.3M) and Mather Group added 72.7% (+$2.9M)
- Zero tracked institutions reduced or exited MPC positions in the quarter
Financial Impact
4 asset managers deployed $87.0M in new capital into MPC, with total tracked holdings reaching $114.1M. No selling activity was recorded among tracked funds.
Risk Factors
- 13F data is stale by 45+ days; positions may have been partially or fully unwound since quarter-end
- All four buyers are asset managers (not activist or event-driven funds), limiting catalyst visibility
- Refining margins are cyclical and subject to macro headwinds (demand, RIN costs, geopolitical factors)
Investment Themes
Documents Analyzed
This report is based on 1 institutional 13F filing from SEC EDGAR.
| Document | Accession Number |
|---|---|
| INST-CLUSTER Data (Synthetic) | inst-cluster-MPC-2026-Q3 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 16, 2026 10d ago | Institutional Cluster | $473.69 | awaiting T+20 | — | — |
Sep 17, 2026 5w ago | Press Release | $424.89 | awaiting T+20 | — | — |
Sep 1, 2026 7w ago | Insider Cluster | $387.00 $420.15 | ▲ +8.57% | ▲ +8.47% | — |
Aug 19, 2026 9w ago | Insider Cluster | $358.23 $424.89 | ▲ +18.61% | ▲ +18.48% | — |
Aug 17, 2026 10w ago | Insider Cluster | $365.21 $413.92 | ▲ +13.34% | ▲ +15.08% | — |
Aug 4, 2026 12w ago | 8-K | $312.61 $383.00 | ▲ +22.52% | ▲ +23.75% | — |
Jun 29, 2026 17w ago | 8-K | $259.22 $309.24 | ▲ +19.30% | ▲ +19.58% | — |
May 6, 2026 24w ago | S-3ASR | $242.17 $267.21 | ▲ +10.34% | ▲ +7.21% | — |
May 5, 2026 25w ago | 8-K | $259.78 $263.06 | ▲ +1.26% | ▼ −3.69% | — |
Apr 21, 2026 27w ago | Court Ruling | $222.07 $258.37 | ▲ +16.35% | ▲ +12.12% | — |
US Market Status
Subscribe to SecBot
Get Real-Time SEC Filing Intelligence
Comprehensive SEC filing analysis delivered the moment filings hit EDGAR. Sentiment scoring, impact analysis, and actionable insights for every material event.
Create a free account Live analysis, Telegram alerts, watchlists and the MCP server for subscribers