Fund manager Cathie Wood, the founder and CEO of ARK Invest, has earned a reputation as one of Wall Street's best stock pickers. And that reputation is well deserved. Over the past one, three, and five years, ARK's flagship Innovation ETF has crushed the broader market.

Given that impressive track record, smart investors may want to keep tabs on what Wood is buying and selling. Recently, she added shares of PagerDuty (PD -1.43%) and UiPath (PATH -1.56%) to ARK's flagship ETF. Here's what you should know about these tech stocks.

Pensive individual overlaid with symbols implying big data and artificial intelligence.

Image source: Getty Images.

1. PagerDuty

PagerDuty is the central nervous system for the modern enterprise. Its platform sits at the center of a company's digital ecosystem, collecting data from virtually all systems and devices. Then, by blending those signals with artificial intelligence, PagerDuty helps its clients predict and prevent the downtime of critical services and technologies.

For example, the PagerDuty platform captures data from application performance-monitoring tools such as Datadog, IT operations hubs such as ServiceNow, public clouds such as Microsoft Azure, customer service software such as, and communications platforms such as Zoom. And when issues are identified, PagerDuty either triggers automatic remediation or alerts the appropriate people, helping them quickly resolve incidents such as website outages or system failures.

As a pioneer in this industry, PagerDuty has 12 years' worth of data and more than 14,100 customers, both of which make the company's artificial-intelligence models more effective. And as new clients join the platform, PagerDuty's data repository will continue to grow, further reinforcing this advantage.

Financially, the company has posted solid top-line growth over the past two years. Trailing-12-month revenue has increased from $142.7 million in the second quarter of 2020 to $244.2 million in Q2 of 2022, which ended July 31, with a compound annual growth rate (CAGR) of 31%. 

Investors should note that PagerDuty is still not profitable on a GAAP basis, and the company generated negative free cash flow of $6.4 million over the past 12 months. However, PagerDuty is still in the early stages of growing its business, and management believes the company has captured less than 1% of its market opportunity.

Here's the bottom line: In an increasingly digital world, delivering a high-quality customer experience is not an option -- it's a necessity. And PagerDuty capitalizes on that fact, helping clients keep their digital ecosystems up and running at all times. Given Wood's focus on innovative technologies such as artificial intelligence, I'm not surprised to see her adding shares of this tech stock to ARK's portfolio.

2. UiPath

UiPath is on a mission to bring automation to every enterprise. To that end, its platform combines three cutting-edge technologies -- artificial intelligence, low-code development, and robotic process automation -- helping clients build, deploy, and manage software bots capable of automating various processes in place of human employees.

To do this, UiPath's bots rely on several types of artificial intelligence, including computer vision, natural language processing, and machine learning. Together, these technologies infuse the bots with the ability to read and understand language, emulate human behavior, and make decisions. In turn, that allows them to automate both simple and complex tasks, such as reviewing emails, completing forms, and extracting data from documents.

One of UiPath's greatest advantages is its partner ecosystem. The company provides prebuilt integrations with hundreds of popular technologies, including Amazon Web Services, Microsoft 365, and Salesforce, meaning clients can quickly automate workflows on these platforms.

Because of the scope of the company's mission and its value proposition to clients, UiPath has grown its top line at an impressive pace. Its trailing-12-month revenue has grown from $451.2 million in the second quarter of 2021 to $736.9 million in Q2 of 2022, which ended July 31, for a CAGR of 63%.

Like PagerDuty, UiPath is currently unprofitable on a GAAP basis and is free cash flow negative. But the company has established itself as the industry leader, according to Forrester Research, and it makes sense to reinforce that advantage by investing aggressively in growth. That's exactly what management is doing.

Here's the bottom line: Automation drives efficiency and productivity by freeing human employees to spend their time on more important tasks, something that would benefit virtually every enterprise in the world. And UiPath has the best product on the market. That's why I'm not surprised to see Wood doubling down on this tech stock.