Generated September 6, 2026.
Overview
ARKX and UFO are both equity ETFs focused on space exploration and related companies, but they differ fundamentally in their selection approach. ARKX is an actively managed fund where ARK Invest's analysts pick holdings based on their conviction about space innovation trends. UFO tracks the S-Network Space Index, a rules-based benchmark that includes companies deriving significant revenue from space activities. Both charge 0.75%, but they construct their portfolios and distribute cash very differently.
How they differ
The biggest difference is management style: ARKX relies on active stock picking, while UFO follows a passive index methodology. This means ARKX's holdings reflect ARK's thematic views on which space companies will lead, whereas UFO holds whatever the S-Network index ruleset dictates—a more transparent, mechanistic approach. For income-focused investors, this creates a structural distinction: UFO returns some value via dividends, ARKX only via price appreciation.
Third, the funds have meaningfully different volatility profiles. ARKX has a beta of 1.71, while UFO registers 1.9—suggesting UFO swings more sharply with broader market moves. ARKX also launched later (03/30/2021) than UFO (04/10/2019), giving UFO a longer track record. Both ETFs have similar AUM: ARKX at and UFO at .
Who each is best for
ARKX: Fits investors who believe in ARK's thematic conviction around space innovation and are comfortable with higher active fees and manager selection risk in exchange for potential outperformance through stock-picking expertise.
UFO: Designed for investors who want transparent, rules-based exposure to the space sector without relying on a single manager's judgment, and who appreciate receiving quarterly cash distributions.
Key risks to know
- Sector concentration and early-stage risk: Both funds invest heavily in space companies, many of which are pre-revenue or early-stage. This creates significant company-specific and sector-wide downside if space commercialization timelines slip or funding dries up.
- Active management underperformance (ARKX): ARK's active approach means ARKX may underperform its benchmark or UFO if manager stock picks don't pan out. Active equity strategies often struggle to beat indexing over long periods, especially in volatile, speculative sectors.
- Higher relative volatility (UFO): UFO's beta of 1.9 indicates it amplifies market swings more than ARKX's 1.71. In a downturn, UFO losses could be sharper, which matters for investors without a very long time horizon.
- Index methodology transparency (UFO): UFO's returns depend entirely on how the S-Network Space Index defines "significant revenue" from space activities. Changes to index rules or reconstitution could trigger unexpected portfolio shifts.
- Price sensitivity to funding environment: Both funds hold companies whose viability depends on venture capital, government contracts, or equity financing. A sustained pullback in space investment or government budget cuts would likely hurt both meaningfully. Both carry significant sector and volatility risk—space remains speculative—so neither is a core holding for conservative portfolios. Past performance does not predict future results.
AI-generated analysis for educational purposes only. Verify important details independently; past performance does not guarantee future results.