MMK - State Street Prime Money Market ETF
MMK seeks to maximize current income while maintaining capital preservation and liquidity by broadly investing in money market instruments. The actively managed fund employs its credit research team to assess the relative attractiveness of instruments based on the general interest rates and market supply/demand imbalances. The fund invests in US government securities (T-bills, notes, and bonds), USD-denominated certificates of deposit and time deposits from banks, US and non-US commercial paper, high-quality company obligations, asset-backed and mortgage-related securities, and repurchase agreements.
- Sector
- Financial Services
- Industry
- Asset Management
- Market Cap
- $25.0M
- Beta
- -0.00
- 52-Week Range
- 99.99-100.32
- Dividend Yield
- $1.38
- IPO Date
- Feb 12, 2026
- Exchange
- NYSE
MMK Options Snapshot
Options pricing data for MMK is refreshed daily after the close. When listed contracts exist, this page surfaces the latest at-the-money implied volatility, max pain strike, dealer gamma exposure (GEX), and 25-delta skew. Listed contracts and live snapshots appear once the options chain has been published by the exchange for the most recent session.
What This Page Covers
The MMK overview links into per-metric analysis views: max pain, gamma exposure, volatility skew, expected move, options chain, open interest history, and aggregate Greeks. Microstructure data is available on short interest, short volume, fail-to-deliver, and market structure.
Frequently asked MMK overview questions
- What is MMK?
- MMK is the ticker symbol for State Street Prime Money Market ETF, an listed exchange-traded fund. MMK seeks to maximize current income while maintaining capital preservation and liquidity by broadly investing in money market instruments. The actively managed fund employs its credit research team to assess the relative attractiveness of instruments based on the general interest rates and market supply/demand imbalances. Listed on NYSE. MMK is the ETF ticker shown on this page; ETF traders use the fund for diversified exposure to its underlying basket, for sector and factor rotation, and for hedging or replication strategies via the listed options chain.
- What are MMK's key statistics?
- State Street Prime Money Market ETF (MMK) carries a market capitalization of $25.0M, 52-week range of 99.99-100.32. Full holdings disclosure, expense ratio, and tracking-error history live on the per-ticker fundamentals page or the sponsor's site; daily NAV and premium/discount-to-NAV are accessible from the same view. These structural inputs frame how the ETF options market prices implied volatility relative to its constituents.
- What sector or industry does MMK belong to?
- State Street Prime Money Market ETF operates in the Financial Services sector, in the Asset Management industry. Sector classification affects how the ticker correlates with sector ETFs, how it reacts to macro factors like rate moves and commodity prices, and how its options pricing compares to sector peers. Compare MMK's implied volatility and skew against sector benchmarks to gauge whether the options market is pricing single-name or systemic risk relative to the broader peer group.
- How current is the MMK data on this page?
- Options snapshots refresh after each trading session; if no snapshot is currently posted for MMK, it usually reflects low options liquidity or a recently listed name. Fund-level fields (sponsor, expense ratio, holdings concentration where available) refresh from the vendor feed nightly. ETF-specific filings (N-CSR, N-PX, N-CEN) update on the SEC EDGAR cadence. FINRA microstructure data refreshes on the source's cadence; for ETFs the off-exchange volume signal is dominated by authorized-participant creation and redemption rather than directional flow.