Rapid-manufacturing expert Proto Labs (PRLB 2.23%) will report its fourth-quarter and 2013 full-year results before the opening bell on Tuesday. For the quarter, analysts expect Proto Labs to bring in $43.7 million in revenue, representing an increase of 30% year over year, which should translate to earnings of $0.37 a share. However, if you're a long-term investor, it's important to read beyond the headlines to see if your investment thesis remains intact. Here's what you need to know about Proto Labs' upcoming earnings.

New CEO in focus
Last quarter, Proto Labs spooked investors when it announced that its highly regarded CEO, Brad Cleveland, who helped grow the company from $1 million a year in sales to over a $100 million a year, announced his plans for departure. Eventually, investors began warming up to the idea as they learned more about his intent behind the decision. Cleveland humbly realized that Proto Labs needed a new CEO to bring the company to even greater glory. In Cleveland's mind, it became time for Proto Labs to find the "builder," the leader who can take the company from a few hundred million in revenue and turn it into a billion-dollar-a-year enterprise.

The search officially concluded a few days ago, and Victoria M. Holt has been named Proto Labs' newest CEO and president. With more than 30 years of Global Fortune 500 leadership experience, Holt has many accolades to her name, including the successful turnaround she engineered as CEO of Spartech, which resulted in a 73% increase in operating earnings in just two years, and ultimately led to the company's acquisition for a 106% premium by PolyOne.

Come Tuesday, Proto Labs investors will get to hear directly from Holt for the first time and get a better sense of her perspective and strategic vision. Based on these first impressions, investors can begin to formulate whether she's the right fit for the job.

Customers served
Because Proto Labs is touted as the world's fastest source for custom CNC machined and injection-molded parts, the company has seen its customer list grow extensively in recent years. In its most recent quarter, Proto Labs served 7,308 unique customers, representing a 23% increase year over year. In addition, Proto Labs was able to increase its revenue per customer by 5%, suggesting that its customers are using its services more. When Proto Labs reports earnings on Tuesday, watch for how many customers it added during the quarter and whether it was able to drive higher spending per customer. If both of these figures continue to rise, it'll be a great sign that the business is in great health and its services remain in demand.

Well suited for today's world
On a high level, Proto Labs primarily serves customers that need up to 10,000 parts manufactured and delivered within 15 business days. In today's world, time has become an increasingly important commodity, and the organizations that use it the most effectively stand to gain a competitive advantage. If you think about it, Proto Labs is uniquely positioned to benefit from this trend, and it's the reason I'm expecting it to deliver another solid quarter of earnings results. Of course, how investors react to the results is anyone's guess, but instead of following the herd mentality, long-term investors will be better served keeping an eye on what the new CEO has to offer and how the company continues growing its increasingly loyal customer base.