Cathie Wood had a quiet first day of trading for the final week of February. The co-founder, CEO, and ace stock picker for Ark Invest executed only four transactions across her family of growth-focused exchange-traded funds. I want to talk about three of them.

Wood added to her existing positions in Amazon (AMZN -1.11%), Iridium (IRDM -0.35%), and Datadog (DDOG -1.70%) on Monday. Let's take a closer look at Ark's latest purchases.

1. Amazon

The leading online retailer is a hub for shoppers, but it's also doing pretty well when it's the one doing the shopping. Amazon has invested $8 billion in AI startup Anthropic, a stake that was valued at $14 billion back in December. Expect that investment to keep rising. Anthropic was hoping to raise $2 billion in its latest round of funding, but on Monday it announced that strong interest led to $3.5 in new seed capital. Anthropic is now valued at $61.5 billion.

Amazon hit an all-time high earlier this month just two days before posting its holiday quarter results, but it's now retreated 12% from its peak value. The fourth-quarter report was beat on both ends of the income statement, but ho-hum guidance cooled the bullish narrative for thee "Magnificent Seven" workhorse.

Image source: Getty Images.

Growth has slowed for Amazon. It has now failed to crack 12% top-line growth in each of the past three years, and that's even as its Amazon Web Services cloud-hosting platform continues to grow a lot faster than that. Net sales climbed just 10% in the fourth quarter, and 11% for all of 2024. This month's financial update that triggered the start of the stock's 12% slide concluded with the e-commerce juggernaut's forecast of just 5% to 9% growth in the current quarter. You have to go back to the summer of 2001 to find the last time Amazon's year-over-year growth was less than the 7% midpoint of its range for the current quarter.

The silver lining is that Amazon's bottom line is growing a lot faster than its top line, but that still doesn't make the stock cheap on an earnings multiple basis. Even after the recent correction, the shares are going for 34 times this new year's expected profit and 28 times next year's profit target. Wood still seems to find value in picking up Amazon while the leading e-tailer is slightly out of favor with investors.

2. Iridium

3. Datadog

Amazon shares are trading slightly lower in 2025, but Datadog has surrendered 18% of its value this year. The entirety of this year's plunge has happened in the past seven trading days, following the release of disappointing fresh financials. Despite the recent slide, Datadog is still a tech success story. The shares have more than tripled since going public in 2019.

Datadog offers cloud monitoring as a service. Its enterprise software modules help a company track a site's downtime and other analytical essentials.

The fourth-quarter results were mixed. Revenue rose 26%, ahead of Wall Street pro expectations. It beat on the bottom line, too.

As with Amazon, it was guidance that crashed the bull party. Datadog expects revenue to clock in flat sequentially, decelerating to 19% growth for all of 2025. It also sees its adjusted earnings moving lower this year. Datadog shares have moved lower in each of those seven days since announcing its results through Monday's close. When Wood believes in a company, she often sees downticks as a buying opportunity.