Updated May 7, 2026 · 2187 articles
Insights
Research, news and field guides on institutional positioning. Powered by real SEC filings — 13F, 13D/G, Form 4.
What Form 13F Doesn't Capture: Blind Spots Decoded
Form 13F is the foundation of institutional ownership analysis — but it has structural blind spots. Shorts, derivatives, foreign equities, and the 45-day reporting lag all create gaps that reading 13F alone will miss.
Sarah MitchellMulti-Brand Asset Manager 13Fs: Franklin, BlackRock, Capital
Multi-brand asset managers aggregate distinct portfolio managers and investment philosophies into a single 13F. Reading aggregator filings requires segmenting tiers by brand and weighting cross-brand confluence as the strongest conviction signal.
Sarah MitchellReading Form 4 M-Codes: Cashless Exercise Plans Decoded
The M+S transaction sequence is the most common Form 4 pattern among S&P 500 CEOs. Reading it correctly distinguishes 10b5-1 cashless exercise plans from discretionary view-driven exits.
Sarah MitchellArista CEO Ullal April 2026: Plan-Driven Sales Pattern
Jayshree Ullal's April 2026 ANET sales follow a multi-quarter 10b5-1 plan execution pattern. Coordinated cadence with founder/CTO Kenneth Duda and GC Marc Taxay reflects firm-wide plan administration, not coordinated bearish positioning.
Alex RiveraUTHR CEO Rothblatt April 2026: Cashless Exercise Pattern
Martine Rothblatt's April 2026 UTHR sales follow the M+S option-exercise + open-market sale pattern — a signature 10b5-1 cashless-exercise plan rather than a discretionary view-driven exit.
Alex RiveraMorningstar Founder Mansueto Sells $1M in May 2026
Joseph Mansueto sold Morningstar shares May 4, 2026. The headline sales of $194K-$380K blocks at ~$170 are routine 10b5-1 plan execution; the founder retains 37.5% beneficial ownership per the most recent 13G/A.
Alex RiveraUnitedHealthcare Cuts 30% of Prior Auth: UNH Holder Read
UnitedHealthcare announced it will cut prior authorization requirements for 30% of medical services. The regulatory pressure narrative is the headline; the holder base — 3,281 institutional filers, 14 active in the top 20, and Capital Group's $13.7B combined active stake — is the structural read.
Alex RiveraPayPal Q1 2026 Earnings & Job Cuts: Holder Base Read
PayPal heads into Q1 2026 earnings with a new CEO, a turnaround strategy, and job cuts. The institutional holder file — 1,716 filers and an active discretionary tier dominated by Capital Research, Citadel Advisors, and Comprehensive Financial Management — reveals whether the turnaround thesis has institutional support.
Alex RiveraCytokinetics ACACIA-HCM Win: Reading the CYTK Holder Base
Cytokinetics announced positive topline results from ACACIA-HCM, the pivotal Phase 3 trial of aficamten in non-obstructive hypertrophic cardiomyopathy. The holder base showed the result coming — five named healthcare specialists in the top 15.
Alex RiveraFMR's $3.1B Disney Stake Held Through the New CEO Pivot
Disney reported $25.2 billion in Q2 revenue alongside a new CEO vision speech. The headline is the revenue print; the more useful read is the holder base — 3,235 institutional filers, 15 active in the top 20, and two recent 13D/G threshold crossings.
Alex Rivera
Marcus ChenCross-Border Sovereign Allocators in US 13Fs: Reading the Tail
Norges Bank holds $935B in US equities. CPPIB holds $149B. Swiss National Bank holds $168B. The cross-border sovereign allocator tail in any US equity's 13F file is one of the most underused signals in institutional flow analysis.
Sarah MitchellWhy Market-Maker 13F Holdings Are Not Conviction
Susquehanna reports $4.4B of COIN. Jane Street reports $3.5B. Citadel Securities reports tens of billions across the market. None of it is institutional conviction. Here's what market-maker 13F notional really represents.
Sarah MitchellReading Custody-Bank 13F Filings: BNY Mellon & State Street
BNY Mellon's $568B 13F and State Street's $2.98T are not what they look like. Custody banks file 13Fs based on intermediary asset positions, not portfolio manager discretion. Here's how to read them.
Sarah Mitchell13G Threshold Crossings vs 13D Activist Filings: A Reading Guide
13G threshold crossings and 13D activist filings both disclose 5%+ beneficial ownership, but they signal completely different intent. Learn what each tells you and how to spot the difference in seconds.
Sarah MitchellHealthcare Specialist vs Generalist 13F: Reading FDA Catalysts
FDA catalyst-driven equities have layered holder structures: specialist healthcare managers, generalist mutual funds, market makers, and post-confirmation cross-border allocators. Learn how to identify each in 13F data.
Sarah MitchellReading Merger-Arb Holders in 13F Data: Pentwater, Sessa & Co.
Merger-arb specialists are visible in 13F filings — but they look very different from long-only conviction holders. Learn how to identify Pentwater, Sessa, and similar event-driven names, and what their position size really tells you.
Sarah MitchellAuvelity FDA Win for AXSM: Reading the Holder Base
FDA approves Axsome Therapeutics' Auvelity for Alzheimer's-related agitation, expanding the drug's label beyond major depressive disorder. The 13F holder file reveals which healthcare specialist managers are positioned for the next leg of the label cycle.
Alex RiveraPentagon AI Roster: Reading Booz Allen's Holder Base
After PLTR was named to the Pentagon's classified AI roster, Booz Allen Hamilton sits in the next tier of federal AI integrators. The institutional holder file shows where active conviction money is sized into the broader defense-AI cycle.
Alex Rivera