Broker-Dealer 13F vs Active Manager 13F: How to Tell Them Apart

Form 13F-HR was designed by the SEC in 1975 to bring transparency to large institutional equity ownership. It does not distinguish between investment styles. The same form is filed by Berkshire Hathaway (a discretionary holding company), Vanguard (a passive index fund complex), Citadel Securities (a market maker), and LPL Financial (a broker-dealer custodian for client accounts). Reading a broker-dealer 13F as if it were a Berkshire-style conviction book is the most common framing error among retail readers. The document looks the same; the meaning is completely different.

What broker-dealer 13F filers actually report

A broker-dealer with custody of client assets reports US-listed equity positions held in those customer brokerage accounts on its 13F-HR. The aggregated file is essentially a snapshot of what the platform's clients collectively own. The platform itself made no investment decision about whether to add NVDA at the top — its clients did, individually, across thousands of accounts.

Common platform-custody filers include:

• LPL Financial LLC (independent broker-dealer with 22,000+ affiliated advisors)
• Schwab brokerage units (custody for self-directed and RIA-served retail clients)
• Pershing LLC (clearing custody for thousands of small-to-mid-size advisor firms)
• Wells Fargo brokerage segments (mixed wealth-management custody and proprietary)
• JPMorgan Chase private banking + custody segments

What active manager 13F filers report

An active manager — Berkshire Hathaway, Sanders Capital, Dodge & Cox, Tiger Global, Bridgewater — reports US-listed equity positions held in funds it directly manages on a discretionary basis. Each position represents a portfolio manager's investment decision: when to enter, when to exit, what weight to carry. The file is a snapshot of conviction.

Five visual signatures that tell them apart

1. ETF concentration in the top ten

Active managers hold individual stocks in their highest-conviction positions. ETFs (especially index ETFs) appear in active manager top-tens only when the manager is using the ETF as a tactical hedge or sleeve.

Broker-dealer aggregated books, by contrast, show 7-9 of their top ten as ETFs because retail and RIA clients overwhelmingly own ETF wrappers. LPL Financial's 2026Q1 13F shows IVV, SPY, QQQ, SPYM, IEFA, SPYG, and VOO across the top ten — eight ETFs out of ten lines. That is the platform-custody signature.

2. Top-ten concentration ratio vs the cap-weighted index

The S&P 500 cap-weighted top-ten was around 36% in early 2026. The Nasdaq-100 top-ten was over 50%. An active manager who picks individual stocks runs higher concentration (Berkshire's top-ten is over 75% of its book) or lower concentration (a deep-value diversifier like Dodge & Cox runs in the 25-30% range).

Broker-dealer aggregated books almost always cluster between 15-25% top-ten concentration — broader than the index, much broader than any active manager. Aggregating across thousands of client accounts mechanically dampens any single-name weight. LPL's 2026Q1 top-ten concentration is 16.9% — pure platform signature.

3. Position turnover quarter-to-quarter

Active managers typically turn over 10-30% of positions per year (5-10% per quarter for low-turnover firms, 30%+ per quarter for high-turnover hedge funds). A 13F that shows roughly the same 500 positions quarter after quarter, with mostly minor share count adjustments, is highly likely to be either a passive index sleeve or a platform aggregation — not active discretion.

Look at the QoQ "NEW position" and "EXITED" counts. Active managers will show 30-80 entries and exits per quarter. Platform custody books show under 20 — the new positions tend to be ETFs that one or two large client accounts adopted, not 100+ stocks added across the book.

4. Filer type taxonomy on 13F Insight

The platform's filer classification system tags every CIK with its functional type — active_manager, passive_index, market_maker, custodian, broker_dealer, sovereign_wealth. The default reading framework should be: only active_manager and sovereign_wealth files convey meaningful investment-conviction signal at the top-of-book level. The "Smart Money" surfaces on the platform deliberately exclude passive_index, market_maker, custodian, and broker_dealer filers from rankings for this reason.

5. AUM source and economic vs reported value

For market makers like Citadel Securities, Susquehanna, Jane Street, the reported 13F value is the notional value of long equity positions used to hedge their option books. The number can be massive ($600B+ for Citadel Securities) but represents inventory, not managed assets. Reading their 13F as a $600B "bet on equities" misses what the firm actually does for a living.

For broker-dealer custodians, the 13F value is real client assets but the economic ownership belongs to thousands of distinct individuals — not the filer. The filer's revenue is the platform fee, not the appreciation of the underlying equity.

A practical reading checklist

1. Open the filer's page on 13F Insight and check the filer type label.
2. Count the number of ETFs in the top ten. Six or more = platform-custody book.
3. Compute top-ten concentration. Under 25% with 3+ ETFs in the top five = platform-custody book.
4. Compare new-position count QoQ. Under 20 with mostly ETF additions = platform-custody book.
5. If the filer is an active manager: read individual position changes as conviction signals. If platform-custody: read aggregate ETF flows as retail/RIA client demand patterns.

Why the distinction matters

Mistaking a broker-dealer 13F for an active manager 13F leads to two specific kinds of error:

• Overinterpreting individual lines — "LPL added $6B to QQQ in Q1" sounds like a conviction call. It actually reflects retail client demand for QQQ via the LPL platform during the spring growth-equity rally — the kind of signal that has zero bearing on QQQ's near-term price direction.
• Underinterpreting flow signals — the same broker-dealer file is genuinely useful for tracking what retail and small-RIA clients are buying. A 14% QoQ jump in IEFA share count tells you that LPL's advisor channel is rotating more international developed exposure into client portfolios. That is a useful demand signal — just not a conviction-trade signal.

13F filings are a powerful data source. Most of the analytical mileage comes from knowing whether the filer at the top of any given file is the actual decision-maker or merely the custody account holder. For more on reading 13F-HR filings and the filer classification system, see the Learn library and the active manager research at the research hub. SEC reference: 13F-HR FAQ on SEC.gov.