Cathie Wood's ARK Invest made some moves this week that are worth a look if you're trying to figure out where the AI trade is headed. The big picture: she trimmed some chip stocks and added to big tech platforms and a biotech name. It's not a wholesale shift, but it does show a more nuanced approach to the AI theme.

The most notable sale was Advanced Micro Devices (AMD), where ARK unloaded about $72 million worth of shares across several ETFs. Chips have been the backbone of the AI rally, so selling into strength could just be profit-taking or rebalancing. For anyone holding semiconductor-heavy ETFs like VanEck Semiconductor ETF (SMH) or iShares Semiconductor ETF (SOXX), it's worth keeping an eye on—but not necessarily a reason to panic.

On the buying side, ARK added to Alphabet Inc. (GOOGL) and Meta Platforms Inc. (META). These are the companies that actually make money from AI through advertising, data, and cloud services. They're closer to the application layer than the hardware layer. If you're looking for ETF exposure that matches this tilt, funds like Communication Services Select Sector SPDR Fund (XLC) or Global X Artificial Intelligence & Technology ETF (AIQ) lean more toward AI applications than pure chips.

Then there's the under-the-radar play: ARK bought over $43 million worth of Intellia Therapeutics Inc. (NTLA). That's a biotech company focused on gene editing and AI-enabled drug discovery. It's a less crowded corner of the AI ecosystem, and it shows Wood is willing to go niche.

None of this screams "big rotation," but it does suggest that within the AI trade, there's a more granular shift happening. For ETF investors, the lesson is to think about AI not as one monolithic bet, but as a collection of segments—hardware, platforms, applications, and even biotech—that might move at different times.