What Is ARKX? ARK Space Exploration & Innovation ETF

ARKX is the ARK Space Exploration and Innovation ETF, an actively managed fund from ARK Investment Management that launched in March 2021. It holds a concentrated portfolio of roughly 30 to 35 companies tied to space, aerospace, defense, and enabling technologies, and SpaceX is among its largest holdings. It charges an expense ratio of 0.75%.

Unlike a passive index fund, ARKX reflects the views of Cathie Wood's ARK research team, which picks and sizes holdings based on its thesis about the space economy. That means high conviction, concentrated positions and returns that can diverge sharply from the broad market, along with an outsized position in SpaceX, which ARK held from before it was publicly listed.

Approximate weights as of mid-2026; refresh quarterly from ARK Invest's fund page. Each ticker links to its individual stock guide in Walnut.

ARKX holds around 30 to 35 stocks, with the top 10 making up over half the fund. Recent leading positions have included SpaceX, L3Harris, Deere, Kratos Defense, Rocket Lab, AMD, AeroVironment, Amazon, Alphabet, and Teradyne. The mix spans launch and satellite companies, aerospace and defense contractors, and enabling technology.

The fund's SpaceX position was private and valued by estimate until the June 2026 listing, and it is large enough that the fund moves with that one name. Because ARKX is concentrated and has leaned toward aerospace and defense names, a handful of holdings can drive much of its return, raising both its upside and its risk.

The most common comparison is UFO, the Procure Space ETF, which is passive, index based, and more purely focused on companies that derive revenue directly from space. ROKT, the SPDR S&P Kensho Final Frontiers ETF, is another passive space and undersea peer. ARKX is actively managed and concentrated by contrast.

The choice comes down to active versus passive, purity of space exposure, and the size of the SpaceX position. ARKX can move sharply on ARK's high conviction picks, while UFO and ROKT offer steadier, rules based exposure. Comparing holdings helps clarify how space focused each really is.

ARKX has been volatile since its 2021 launch, reflecting its concentrated, growth heavy portfolio and the early stage nature of many space and defense names. Its active strategy means performance can diverge widely from broad market indexes over both short and long periods.

The long term thesis rests on growth in the space economy, including launch, satellites, defense, and enabling technologies. That trend is real, but many holdings are early stage or dual purpose, and the concentration in SpaceX means one name drives a large share of the outcome. Investors should expect significant volatility and size positions accordingly.

ARKX may fit investors who want a high conviction, actively managed bet on the space economy and who can tolerate sharp volatility, concentration, manager risk, and an outsized SpaceX position. It is less suited to those who want low cost, diversified, or income focused exposure, given its 0.75% fee and negligible dividend.

Walnut is not an investment adviser, and this is not a recommendation. Whether ARKX belongs in your portfolio depends on your goals, time horizon, and appetite for thematic and single stock risk. Many investors who hold funds like this keep them as a small satellite alongside a diversified core.

ARKX trades on major US brokerages including Robinhood, Fidelity, Schwab, and Public. Many of these support fractional shares, so you can invest a fixed dollar amount rather than buying whole shares. As an actively managed fund, expect more turnover and volatility than a passive index ETF.

You can also connect your brokerage account to Walnut to track ARKX alongside your other holdings and thematic portfolios, and to see how a space and defense position fits your overall targets. Walnut helps you monitor and plan, while your trades continue to execute at your own broker.

ETFs are passive bundles; thematic portfolios in Walnut let you concentrate within them. If you hold ARKX as a core position, these are the themes you might layer on as satellites.

There are three common ways to get ARKX exposure. Buy shares (or fractional shares) of ARKX directly at any major broker that lists it. Hold it as a core position and layer more concentrated ideas on top. Or build it into a thematic portfolio in Walnut, so ARKX sits alongside other holdings that express the same thesis, with target weights you can rebalance toward. ARKX trades like a stock during market hours, so you buy it the same way you would any listed share.

New to buying funds? See how to buy an ETF, step by step.

Whether ARKX is a good buy depends less on any single call and more on your time horizon and what you already hold: it tracks Actively managed, so the real question is whether you want that exposure in your mix and at what weight. We walk through valuation, concentration, and what would have to be true for it to outperform from here in is ARKX a buy?

ARKX is a concentrated, actively managed bet on space, aerospace, and defense innovation at a 0.75% fee. It offers concentrated exposure to the space economy, including a large SpaceX position, but with high volatility and manager risk. Most investors treat it as a small thematic satellite.

Whether ARKX is worth buying today depends more on your time horizon and what you already hold than on any single call. We walk through valuation, concentration, and what would have to be true for it to outperform from here in is ARKX a buy?

ARKX yields ~0% as of mid-2026, paid by passing through the dividends of its underlying holdings. For the payout schedule, history, and how the distributions are taxed, see ARKX dividend: yield and schedule.

New to funds like ARKX? Start with what an ETF is, then how to buy an ETF, or browse the full guide to ETF investing.