Why do options market makers file 13F reports?

Any institutional investment manager exercising discretion over $100 million or more in Section 13(f) securities must file a 13F-HR with the SEC. Because options market makers hold large equity positions as hedges, they easily exceed this threshold and are required to report.

Does a market maker holding millions of shares mean they are bullish on that stock?

No. Market maker equity positions are delta hedges against options inventory. A large position in NVIDIA shares, for example, likely reflects heavy options trading volume in NVIDIA, not a directional bet on the company.

How can I tell the difference between a market maker and a traditional fund in 13F data?

Look for ETF-heavy top holdings (SPY, QQQ, IWM), extremely high position counts, rapid AUM swings between quarters, and populated put/call columns. Traditional asset managers tend to have more concentrated, stock-focused portfolios with stable quarter-over-quarter values.

Should I ignore options market maker 13F filings entirely?

Not entirely. Changes in their positions can reveal shifts in options market flow and liquidity conditions. However, their absolute position sizes should not be interpreted as investment conviction the way you would for a pension fund or mutual fund.

How Options Market Makers Distort 13F Holdings Data

When retail investors scan 13F filings for the largest institutional holders, names like Susquehanna International Group routinely appear near the top with reported values exceeding $800 billion. That figure places SIG alongside Vanguard and BlackRock in raw dollar terms. But the comparison is misleading, because Susquehanna is an options market maker, not a traditional asset manager.

TL;DR

Options market makers like Susquehanna, Citadel Advisors, and Jane Street file 13F-HR reports that include the notional value of equity options positions alongside their stock and ETF hedges.
The resulting "reported 13F value" vastly overstates their actual economic exposure to the market.
SPY, QQQ, IWM, and other broad ETFs dominate their top holdings because these are hedging instruments, not directional bets.
Investors should treat these filings as a map of market-making activity, not a portfolio to copy.

What Is an Options Market Maker?

An options market maker provides liquidity by continuously quoting bid and ask prices on options contracts. When a retail investor buys a call option on Tesla through their brokerage, an options market maker is often on the other side of that trade. To manage the risk from holding thousands of simultaneous options positions, the firm delta-hedges by buying or selling the underlying stock or ETF.

This hedging activity is what shows up in the 13F filing. The firm does not "want" to own 224 million shares of NVIDIA or $77 billion of SPY. These positions exist to offset options risk.

Why Reported 13F Value Is Not AUM

For a traditional asset manager like Fidelity (FMR) or Capital World Investors, the 13F value closely approximates the assets they manage on behalf of clients. When Fidelity reports $1.96 trillion, that represents real client money invested in stocks.

For an options market maker, the 13F value is a byproduct of hedging. Consider Susquehanna's Q4 2025 filing:

Metric	Susquehanna (SIG)	FMR (Fidelity)
Reported 13F value	$868 billion	$1.96 trillion
Business model	Options market making	Asset management
Top holding	SPY (9.6%)	NVDA (10.3%)
Positions	13,927	5,139
Represents	Hedging book	Client portfolios

The $868 billion figure for Susquehanna includes the value of shares held as delta hedges against options books. The actual capital at risk is a fraction of this number.

How to Spot an Options-Heavy Filer

Several signals help identify when a 13F is dominated by options market-making activity:

ETF concentration in top holdings: When SPY, QQQ, IWM, and GLD dominate the top positions, the filer is likely hedging broad market exposure rather than making stock picks.
Unusually high position count with broad diversification: Market makers hold positions across thousands of names because they provide liquidity across the entire listed options market.
Rapid AUM swings between quarters: A 20-30% quarterly change in reported value often reflects shifts in options inventory and hedging needs, not capital inflows or outflows.
Put and call columns populated: 13F filings include columns for put and call options. When these are heavily populated, the underlying share positions are hedges.

The Biggest Options Market Makers Filing 13Fs

Firm	Q4 2025 Reported 13F Value	Primary Business
Susquehanna International Group	$868 billion	Options market making, quantitative trading
Citadel Advisors	$666 billion	Multi-strategy hedge fund + market making
Jane Street Group	$662 billion	Quantitative trading, ETF market making

Combined, these three firms report over $2 trillion in 13F value. None of that represents traditional assets under management in the way investors typically understand the term.

What Investors Should Do With This Information

When you see an options market maker appear as a top holder of a stock you own, it does not signal institutional conviction in that company. Instead:

Filter by filer type: Focus on traditional asset managers, mutual funds, and pension funds when analyzing institutional ownership signals.
Check the WhaleScore: On 13F Insight, WhaleScore helps identify filers whose holdings carry genuine signal value versus those dominated by trading activity.
Look at position changes, not absolute size: Even for market makers, meaningful quarter-over-quarter changes in specific positions can signal shifting options flow and market sentiment.
Use "reported 13F value" language: When discussing these firms, always say "reported 13F value" rather than "AUM" or "assets under management" to avoid implying traditional investment management.