Ladies and gentlemen, thank you for standing by, and welcome to NETSCOUT's third quarter fiscal year 2022 financial results conference call. At this time, all parties are in a listen-only mode until the Q&A session portion of the call. As a reminder, this call is being recorded. Tony Piazza, Vice President of Corporate Finance, and his colleagues at NETSCOUT are on the line with us today. If you require operator assistance at any time, please press star and zero. I would now like to turn the call over to Tony Piazza to begin the company's prepared remarks.
Thank you, operator, and good morning, everyone. Welcome to NETSCOUT's third quarter fiscal year 2022 conference call for the period ended December 31st, 2021. Joining me today are Anil Singhal, NETSCOUT's President and Chief Executive Officer, Michael Szabados, NETSCOUT's Chief Operating Officer, and Jean Bua, NETSCOUT's Executive Vice President and Chief Financial Officer. There is a slide presentation that accompanies our prepared remarks. You can advance the slides in the webcast viewer to follow our commentary. Both the slides and the prepared remarks can be accessed in multiple areas within the investor relations sections of our website at www.netscout.com, including the IR landing page under Financial Results, the webcast itself, and under Financial Information on the quarterly results page. Moving on to slide number three, today's conference call will include forward-looking statements.
Examples of forward-looking statements include statements regarding our future financial performance or position, results of operations, business strategy, plans and objectives of management for future operations, and other statements that are not historical facts. You can identify forward-looking statements by their use of forward-looking words such as anticipate, believe, plan, will, should, expect, or other comparable terms. We caution listeners not to place undue reliance on any forward-looking statements included in this presentation, which speak only as of today's date. These forward-looking statements involve risks and uncertainties, and actual results could differ materially from the forward-looking statements due to known and unknown risks, uncertainties, assumptions, and other factors, which are described on this slide and in today's financial results press release, as well as in the company's annual report on Form 10-K for the year ended March 31st, 2021, on file with the Securities and Exchange Commission.
NETSCOUT assumes no obligation to update any forward-looking information contained in this communication or with respect to the announcements described herein. Let's turn to slide number four, which involves non-GAAP metrics. While this slide presentation includes both GAAP and non-GAAP, GAAP results, unless otherwise stated, financial information discussed on today's conference call will be on a non-GAAP basis only. The rationale for providing non-GAAP measures, along with the limitations of relying solely on those measures, is detailed on this slide and in today's press release. These measures should not be considered in isolation from or as a substitute for financial information prepared in accordance with GAAP. Reconciliations of all non-GAAP metrics with the applicable GAAP measures are provided in the appendix of the slide presentation in today's earnings press release, and they are also on our website. I will now turn the call over to Anil for his prepared remarks.
Anil?
Thank you, Tony. Good morning, everyone, and thank you all for joining us today. Let's begin on slide number six with a brief recap of our third quarter and first nine months non-GAAP results. During the third quarter, we delivered strong performance across the board. Higher quarterly sales, margins, and profitability were mainly driven by increased enterprise customer demand and customers' acceleration of orders, primarily within our service provider vertical of approximately $25 million-$30 million that were previously forecasted to occur in our fourth quarter. As a result, we achieved strong top-line growth with revenue increasing more than 14% year-over-year to $262.2 million. Product revenue grew more than 25%, and service revenue grew more than 3%, both on a year-over-year basis.
We exited the third quarter with a product backlog of approximately $30 million in unshipped orders, which excludes radio frequency propagation modeling orders. Moving to our bottom line, based on the third quarter's revenue performance and product mix, diluted earnings per share increased to $0.89 from $0.66 a year ago, an increase of approximately 35%. On a year-to-date basis, revenue in the first nine months of fiscal year 2022 increased more than 7% to $664.4 million. This was driven by product revenue growth of more than 17%, partially offset by 0.8% decline in service revenue. Diluted earnings per share increased approximately 29% to $1.56 for the first nine months of the fiscal year. These comparisons are all made on a year-over-year basis.
In summary, our strong third quarter performance has further demonstrated the financial strength of our business model. This success, combined with our year-to-date results, has provided us with even greater clarity into our full fiscal year outlook and the confidence to update it. I'll provide more details on all of this later in my remarks. Let's now move to slide number seven for some further perspective on market and business insights. Starting with markets, we continue to see digital connectivity increasing around the world, accelerated by the pandemic and longer-term technology trends. NETSCOUT now has more than three decades of experience providing service assurance and cybersecurity solutions at the crossroads of modern business performance and cutting-edge technology. Since our inception, we have developed a solid reputation for being innovative, delivering industry-leading solutions, and cultivating close-knit customer relationships.
Our established mind share and best-in-class solutions have positioned us well to capitalize on the world's growing connectivity. To address the latest challenges of customers dealing with the new normal, hybrid workforces, edge connectivity, and ever-expanding cybersecurity threat landscape, we recently released several new products, including Smart Edge Monitoring and our Omnis Cyber Intelligence. We are excited about the potential of these recently released products and services, which are starting to gain traction. We believe that these offerings will further accelerate our business momentum in the next fiscal year and beyond. We are also actively working with many of our partners to better integrate our solutions into their ecosystems, and thereby enhance the overall quality and technical capabilities of their technology tools. Michael will provide more context on these developments during his remarks.
Now I would like to discuss our customer verticals to provide more perspective on our performance, as well as the related trends that we are seeing. For the first three quarters of fiscal year, we grew revenue in our service provider customer vertical by more than 7% year-over-year. As mentioned earlier, in the third quarter, several service provider customers accelerated orders with us that were previously anticipated to occur in the fourth quarter of fiscal year 2022. In terms of trends for this vertical, we continue to see 5G deployed globally, and our radio frequency propagation modeling solutions being used in carrier planning. Last week, for example, two tier one domestic carriers lit up their 5G networks as they leverage mid-band spectrum to deliver their solution.
Meanwhile, the latest FCC mid-band spectrum auction in the U.S. just raised over $22 billion. These events further underscore the industry's steady progress and persistent interest in 5G-related initiatives. We continue to win notable service provider deals in the third quarter, which included more 5G-related orders from tier one domestic and international carriers. We also won a second large radio frequency propagation modeling order from a tier one domestic carrier as the organization continues to advance its 5G network planning. Michael will comment on some of these service provider wins in his remarks. Now moving to our enterprise customer vertical. Revenue for this vertical grew by more than 7% year-over-year in the first three quarters of our fiscal year.
In line with our remarks from last quarter, we continue to see enterprise customers moving from reactivity to proactivity in their execution as they restart projects previously delayed by the pandemic and adjustment to the new normal of today's operating environment. Michael will highlight some of the customer wins we achieved during the quarter in this vertical in his remarks. Now let's move to slide number eight to review our outlook. Looking back on our business performance so far, we have delivered three quarters of solid results with strong business momentum. Importantly, our third quarter performance has demonstrated the financial strength of our business model and provided us with even greater clarity and confidence regarding our fiscal year 2022 forecast. We remain on track to meet our financial objectives for the full fiscal year.
After considering all these factors, we have made the decision to update our full year guidance, raising our revenue midpoint and increasing our EPS outlook for the fiscal year 2022. These updates reflect our expectation for lower product revenue in the fourth quarter, attributable to the previously mentioned acceleration of orders by customers and movement of revenue from fourth quarter to our third quarter results. It also reflects our expectation to end the fourth quarter with a product backlog of unshipped orders similar to that of the third quarter. Jean will provide additional color and recap on the numbers in our remarks. In conclusion, we have performed well year to date. Our visibility has further improved, and our business model has demonstrated significant financial strength.
We remain excited about our future growth prospects, and I look forward to sharing our final fiscal year 2022 results and our fiscal year 2022/2023 outlook with everyone on our next earnings call. With that, I'll turn the call over to Michael.
Please turn to slide nine. Thank you, Anil, and good morning, everyone. Slide 10 outlines the areas that I will be covering today. Customer wins. We continue to see momentum around 5G in our service provider customer vertical. As Anil mentioned, we received 5G-related orders from both the domestic tier one as well as international carriers in the third quarter. One of these deals was a low eight-figure order for our 5G-related solutions from a certain domestic tier one carrier, which represents the third 5G-related order this carrier has placed with us. The international market also continued to show momentum. We received a mid-seven-figure order for 5G-related solutions from an international carrier in the third quarter, which represents the second 5G-related order from this organization.
We also received the second low eight-figure order from a domestic tier one carrier from additional radio frequency propagation modeling services as the carrier continued to plan its 5G network build out. As these carriers increasingly look to integrate 5G capabilities and further advance the competitiveness of their offering, our unique combination of market leading solutions, depth of experience, responsive customer service, and strong relationships continue to win us business in this service provider segment. We have also continued to observe renewed momentum within our enterprise customer vertical. As Anil touched on earlier, these customers are now in the process of refocusing on those important projects that were either previously delayed due to the pandemic constraints or newly created as a result of the broad impact of the pandemic on underlying digital transformation trends today.
We are well positioned to capitalize on this momentum, and our robust suite of offerings is gaining traction with both existing and new enterprise customers. During the third quarter, for example, we won a low seven-figure deal with a new customer that is a global household and consumer products company headquartered in the U.S. By demonstrating to the customer our ability to help protect its critical business services from disruptions, we were able to win this deal after only a very short sales cycle. Once the customer's IT operations experienced a massive data center breakdown, their IT operations management team realized they did not have the ability to resolve, let alone prevent such problems using their existing tools. This is another example of rapidly growing complexity within IT today.
IT has already reached a critical threshold that necessitates visibility at a larger scale than possible with conventional IT tools. Beyond this example, and due to the result of similar IT challenges, we have won several noteworthy new clients, including a new agency in the U.S. Department of Defense. These wins further demonstrate the highly differentiated nature of our approach, as well as the depth and breadth of our offering, which continue to serve us well in today's dynamic and constantly evolving digital economy. Now turning to our go-to-market activities. On this front, we remain focused on cultivating strong partnerships, integrating solutions, and preparing for our ENGAGE 2022 Annual User and Technology Summit. From a partnership and integration perspective, we recently announced several new and continuing collaborations.
To highlight a few, in early November 2021, we reported that AWS customers will now be able to use Omnis Cyber Intelligence or OCI integration with AWS Security Hub for added visibility and security when migrating workloads to AWS. Earlier this month, we also announced our collaboration with AWS in support of ENGIE IT, the IT subsidiary of a worldwide low carbon energy supplier, ENGIE, to seamlessly migrate its workloads and services to the cloud in support of the company's digital transformation journey. Finally, at the end of the year, we announced a new integration that connects NETSCOUT's nGeniusONE service assurance solution with ServiceNow IT Operations Management or ITOM, visibility and ITOM Health. Our integration module is enabling nGeniusONE to generate enhanced alerts to ServiceNow ITOM with a contextual launch capability for service triage.
We are excited about these partnerships, the people we are working with and the quality of our solution integration thus far. Through these collaborations, we can help our customers navigate our increasingly connected and interdependent world with more confidence and protection, so they can focus on what matters most to their organizations. Looking ahead, NETSCOUT plans to host its customers and partners at its annual ENGAGE Technology and User Summit from April 25th- 28th this year in Orlando, Florida. As an annual tradition, this event is a true highlight of the year for NETSCOUT. At ENGAGE 2022, we plan to showcase our cybersecurity service assurance and DDoS capabilities through presentations, panel discussions, demonstrations, and hands-on training. This event will also provide us with more opportunities to meet with our user and partner communities to discuss and solicit feedback regarding our Visibility Without Borders offerings.
That concludes my prepared remarks, and I will now turn the call over to Jean.
Thank you, Michael, and good morning, everyone. I will now review our key third quarter and year-to-date fiscal year 2022 metrics. As a reminder, this review focuses on our non-GAAP results, unless otherwise stated, and all reconciliations with our GAAP results appear in the presentation appendix. Regardless, I will note the nature of any such comparisons. Slide 12 details the results for our third quarter and year-to-date fiscal year 2022. Focusing on the quarterly performance, revenue grew 14.6% over the same quarter in the prior year to $262.2 million. Product revenue grew 25.6%, and service revenue grew 3.5% over the prior year's quarter.
Our third quarter fiscal year 2022 gross profit margin was 78.8%, up 0.2 percentage points over the same quarter last year, primarily attributable to product volume and mix. Our third quarter software-only revenue was 34% of our service assurance product revenue, compared to 31% in the same period last fiscal year. Quarterly operating expenses increased 3.5% from the prior year, largely due to investments in sales and marketing. We reported an operating profit margin of 33.2% compared with 28.2% in the same quarter last year. Diluted earnings per share was $0.89 compared with $0.66 in the same quarter last year. Turning to slide 13, I'd now like to review key revenue trends for the first nine months of fiscal year 2022.
Year to date, the service provider customer vertical revenue grew approximately 7.4%, while the enterprise customer vertical grew approximately 7.7%. Approximately 51% of total revenue for the first nine months of the fiscal year was generated from the service provider customer vertical, while the remaining 49% was from the enterprise customer vertical. Turning to slide 14, which shows our geographic revenue mix on a GAAP basis. Revenue by geography continues to be domestically weighted. Both domestic and international revenue increased on a year-to-date basis. For both the third quarter and first nine months of the fiscal year, there was one customer that represented 10% or more of total revenue. Slide 15 details our balance sheet highlights and free cash flow.
We ended the quarter with $553.5 million in cash equivalents, and short-term and long-term marketable securities, representing an increase of $77.7 million since the end of the second quarter. Free cash flow generated in the quarter was $90.3 million. We repurchased approximately $11 million or 409,379 shares of our common stock in the quarter. From a debt perspective, as of the end of the third quarter, we had $350 million outstanding on our $800 million revolving credit facility, which expires in July 2026. To briefly recap other balance sheet highlights, accounts receivable net was $233.9 million, up by $36.2 million since the end of March.
The DSO metric was 76 days versus 75 days at the end of the fiscal year 2021, and 70 days at the same time last year. Moving to slide 16 for commentary on our outlook, I will focus my review on our non-GAAP outlook. As Anil noted earlier in his remarks, we have updated our full year outlook, raising our revenue midpoint and increasing our EPS outlook for fiscal year 2022. We now expect fiscal year 2022 revenue to be in the range of $850 million-$855 million. Assuming approximately 75 million weighted average diluted shares outstanding, we expect non-GAAP diluted earnings per share to be between $1.75 and $1.78.
This update reflects our expectation for lower product revenue in the fourth quarter as a result of the previously mentioned acceleration of product revenue of approximately $25 million-$30 million from the fourth quarter into our third quarter results. It also reflects our expectation to end the fourth quarter with a product backlog of unshipped orders of approximately $30 million, which excludes radio frequency propagation modeling projects and is similar to that backlog of the third quarter. That concludes my formal review of our financial results. I'll now turn the call over to the operator to start Q&A.
At this time, if you would like to ask a question, please press star and one on your telephone keypad. If you wish to remove yourself from the queue, press the pound key. We do ask that in the interest of time, you limit yourself to one question and one follow-up. We will take our first question from Matt Hedberg with RBC Capital Markets.
Hey, guys. Thanks for taking my questions. Congrats on the quarter.
Sure.
Anil, obviously, there's a lot of positives this quarter, and I guess I'm curious, you know, the acceleration in service provider deals this quarter, is it just a function of timing, or was there anything else that caused some of these deals to accelerate this quarter?
Matt, I think the main reason was, as we have mentioned, a little bit of this happened in last quarter also. I mean, the big deals often done by big service provider customers with large orders has some challenges with many other vendors who have a bigger hardware content because of supply chain problems. As a result, they wanted to use the year-end budgets, and that we think is the most, I mean, most likely reason why we got Q4 orders moved into Q3. That's a fact which has been happening, but it was more prominent in the third quarter, because even though it's the third quarter for us, it's a fourth quarter fiscal quarter for all of them.
That put a lot of pressure on us to ship things, but we had to do it because of customer satisfaction reasons.
Got it. That makes a ton of sense. Then I think, you know, one question that we get from a lot of investors is potential questions about supply chain constraints. It doesn't look like that impacted you this quarter or in your guidance, but any commentary on, you know, if that's something you guys think about, just kind of given your global reach?
Well, yeah, we see that also, but they have not been detrimental to our revenue and orders. For example, there are challenges in disk drives. We use a lot of disk drives for packet recording and everything. Sometimes we have to pay more. We have been managing our margin despite paying some higher costs. We have those problems, but we don't make custom hardware, but we do use a lot of hardware from third parties and otherwise. There have been people who buy hardware from a preferred supplier, and there we had to work with them to keep enough of them. There are people who buy directly from other vendors, and those things have been delayed.
As a result, sometimes it affects the delay of the shipment of our orders also. Overall, I feel that the challenges we are facing also, but they pale in comparison to many other companies in our space.
Got it. That makes a ton of sense. Thanks, Anil. Thanks, everybody.
Sure.
Thank you.
We will go next to James Fish with Piper Sandler.
Hey, guys. Nice execution there. On the guide, it was another quarter in which you cite a pull-in of deals. I guess what makes you think it's more of a pull-in of deals rather than just rising demand or even an acceleration of the 5G cycle in terms of the timeframe as deferred revenue also was materially higher than normal. Is there any way to think about also your total backlog sequentially, including radio frequency? Really what I'm trying to understand is why wouldn't we have seen, you know, a larger guide raise here on the strength the last few quarters, the demand environment and upside in lead metrics?
Well, the main reason is because we have the forecast and very credible forecast in December for the Q4. We see clear decrease in forecast for Q4 from the sales team as a result of what happened in Q3. That's the primary reason, like, for all these big deals, eight-digit deals, we have, I mean, clear idea of which quarter they generally will fall. That's what happened this time that our forecast for Q4 for those very large customers has correspondingly decreased in Q4 versus Q3. I wish that there is a 5G acceleration, and that'll be great for us.
Yes, there is a lot of talk about 5G, but we don't think that ex-5G acceleration is the primary reason for this earlier than expected orders.
Hi, James, this is Jean. I just want to comment on one of your observations about deferred revenue and put it in context of the backlog. As you know from our Q disclosure, our backlog was about, just round numbers, $80-$85 million at the end of Q2. In total, the backlog exiting Q3, including radio frequency calibration, is about $75 million. That is actually a portion of that you'll see sitting in deferred revenue, because one of our large carriers asked to us to please bill them for the project before it was actually completed. You'll see the deferred revenue is up by $20 million-$25 million due to that, and that's one of the reasons why the DSO is up at 76, because the invoice went out, but the revenue hasn't been recognized yet.
That's very helpful. Jean, on the security side, you know, obviously service assurance had a really good quarter. Didn't hear as much on the security element. Can you just give us an update on what percentage of revenue security represents for you today? What it grew year-over-year and the breakdown within Arbor only between service provider and enterprise?
I would say that Arbor is still roughly on our guidance, probably roughly just round numbers, 25%. For the quarter, they grew in the mid-teens, and they grew mostly in service provider and were relatively flat in enterprise. On a year-over-year basis, their overall growth is approaching the mid-single digits. It's skewed mostly towards service provider, and enterprise tends to be flat on a year-over-year basis.
Helpful. Thanks, guys.
Yeah.
Thank you.
We will go next to Kevin Liu with K. Liu & Company.
Hi, good morning. I just wanted to start on the service provider side as well. You know, obviously you had the prior C-band auction and now some of that is getting lit up by your large Tier 1s, and you've seen some benefit to your product revenue growth. Wondering if you could kind of walk us through, you know, subsequent to the prior C-band auction, how that sort of benefited your business or flowed into it and what you expect, you know, following the latest round of mid-band auction.
There are two factors, Kevin. One is that we are the incumbent in the 4G space, and so as they come out with 5G RFPs and all that, we still have to go through the mechanics of winning the bidding business. Our 5G bids are really extension of our 4G incumbency and all the investments we have made. All the carriers we were talking about, Michael had talked about, are really doing 5G as an extension of our success in 4G. That's about the previous spectrum and all this. The new spectrum oftentimes requires new propagation modeling solutions. We think that as new spectrums are laid out, it's going to affect our propagation-based solution, which Michael talked about, which we got two large orders.
We have been working with smaller carriers now and on a more software-based solution for propagation measurements, which could be applicable and more cost effective for them. That's what I look at, existing spectrum moving from 4G to 5G as a result of our RNC and C. For the planning purposes on the new spectrum, we have these second kind of orders.
Got it. Maybe switching over to the enterprise side of things, you guys have seen kind of building momentum there over the course of the year. You know, as you look forward here, do you feel like this is kind of a good cadence in terms of where you want growth to be for this vertical? Or do you see further opportunity for acceleration?
Yeah, we see that, even though there was not a big contribution of this in this year, but the two big areas we announced, Smart Edge Monitoring for service assurance solution beyond the data center, and Omnis Cyber Intelligence, which we feel is the adjacency with a big market size for us, are both tracking very well. While there is not much contribution to these because of we just released them three months-six months ago, there is a lot of interest. We already have quite a few customers, and we think that's going to be a big driver for growth next year in the enterprise.
I might want to add just one other point. I do believe that there is a growing need for our scale solutions, scale of visibility that other tools cannot handle. That's because of the growing complexity and all these additional digital transformation moves is inevitable for large customers to arrive at needing our kind of solutions. That I see that trend.
Yeah.
All right. Well, that's certainly great to hear. Congrats on the strong quarter, and thanks for taking the questions.
Thank you.
We have no further questions at this time. I'll turn it back to the speakers for any closing remarks.
Great. Thank you for joining us today. This now concludes our call. Have a nice day. Thank you.
This does conclude today's program. We appreciate your participation, and you may now disconnect.