Greetings. Welcome to the Aurora Q4 and Full Year 2021 Business Review Call. At this time, all participants are in a listen-only mode. A question and answer session will follow the formal presentation. If anyone should require operator assistance during the conference, please press star zero on your telephone keypad. Please note this conference is being recorded. I will now turn the conference over to your host, Stacy Feit, Vice President of Investor Relations. Thank you. You may begin.
Thank you. Good afternoon, everyone, and welcome to our Q4 and Full Year 2021 Business Review Call. At this time, all participants are in a listen-only mode. Later, we will conduct a question and answer session and instructions will be given at that time. If anyone should require operator assistance, please press star then zero on your touch-tone phone. As a reminder, this conference call is being recorded. We announced our results earlier this afternoon. Our shareholder letter and a presentation to accompany this call are available on our investor relations website at ir.aurora.tech and were furnished with our Form 8-K filed today with the SEC. On the call today are Chris Urmson, Co-founder and CEO, and Richard Tame, CFO.
Chris will provide an update on the progress we have made across the key pillars of our business, and Richard will recap our 2021 financial results. We will then open the call to Q&A. A recording of this conference call will be available on our investor relations website at ir.aurora.tech shortly after the call has ended. I'd like to take this opportunity to remind you that during the call, we will be making forward-looking statements. This includes statements relating to the expected performance of our business, future financial results and guidance, strategy, long-term growth, and overall future prospects. These statements are subject to known and unknown risks and uncertainties that could cause actual results to differ materially from those projected or implied during this call.
In particular, those described in our risk factors included in our Form S-1 filed by us with the SEC on 12 November 2021, and our Form 10-K for the full year 2021 that will be filed by 31 March 2022, as well as the current uncertainty and unpredictability in our business, the markets and economy. You should not rely on our forward-looking statements as predictions of future events. All forward-looking statements that we make on this call are based on assumptions and beliefs as of the date hereof, and Aurora disclaims any obligation to update any forward-looking statements except as required by law. Our discussion today will include non-GAAP financial measures. These non-GAAP measures should be considered in addition to and not as a substitute for or in isolation from our GAAP results.
Information regarding our non-GAAP financial results, including a reconciliation of our historical GAAP to non-GAAP results, may be found in our shareholder letter, which was furnished with our Form 8-K filed today with the SEC and may also be found on our investor relations website. With that, I will now turn the call over to Chris.
Thank you, Stacey, and welcome everyone to our first business review call. Today, we are pleased to share our Q4 and Full Year results for the first time as a publicly traded company. 2021 was an incredible and transformative year for Aurora. We acquired Uber's self-driving vehicle business, which brought an incredible team of talent and important technology to Aurora. We solidified a number of powerful partnerships and pilots. We partnered with two of the top three North American truck OEMs with PACCAR and Volvo, with the No. 1 carrier in the US with FedEx, with Uber Freight, a transformative logistics platform, with the No. 1 ride-hailing platform with Uber, and with the No. 1 auto OEM with Toyota. We continue to advance our cutting-edge technology.
We're making progress on our sensor suite, which includes our proprietary FirstLight Lidar, our Aurora Driver software, and with our on-road and virtual testing. We introduced Aurora Horizon, our trucking product, and Aurora Connect, our ride-hailing product, both of which are underpinned by the Aurora Driver. Of course, we took our company public. Already in 2022, we have continued to make powerful progress through our development and in our partnerships and pilots as we work towards the launch of our autonomous trucking business in late 2023 and our ride-hailing business in late 2024. Before we talk more about our progress, I'd like to take a moment to share why we founded Aurora. Together, Drew, Sterling, and I founded Aurora five years ago because we saw an incredible opportunity to deliver the benefits of self-driving technology safely, quickly, and broadly.
We believe in the meaningful impact self-driving vehicles will deliver to our society, and we saw a path to bringing self-driving technology to market focused first on safety, then speed, then breadth of impact. To deliver on our mission, we architected our company, our technology, our path to market, and our partnerships to uniquely facilitate this emphasis on safety, speed, and breadth. We began by developing on light vehicles. These allowed us to move more quickly while we built out our foundational capabilities. We understood that to operate safely, we needed a multimodal sensor suite that could see at long ranges, enable more rapid reaction than the sensors that were available in the market. We designed the Aurora Driver with a common core of technology that is vehicle agnostic.
This allowed us to focus on a single architecture while also enabling Aurora's technology to integrate with multiple vehicle types from a Class 8 truck to a passenger sedan. We expect this approach will unlock a powerful market opportunity and allow us to move quickly in both spaces. Along with our approach to technical development, we also focused early on to establish deep collaborative partnerships which we believe will accelerate our path to commercialization. When we think about what we need to accomplish and how we're executing against our plan, we measure our progress through our technical development, the incremental validation of our safety case, our lessons learned through our pilots, and progress with our partners. I'd like to start with an update on our pilots, why they're important, and how they're going. Pilots are an integral step toward building our commercial business.
They're one of the ways we gain valuable insight as we continue to refine the Aurora Driver, Aurora Horizon, and Aurora Connect as we prepare for commercial launch. Through our pilots, we gain a deep understanding of our customers' needs, including operational requirements. We build trust with our partners as we regularly, autonomously move goods under the supervision of vehicle operators while maintaining on-time performance and striving for operational excellence. We measure progress by what we're learning and how we're improving. We look at product refinement, network integration, and the operational learnings we achieve. We use these experiences to build a safe, reliable, and robust product. We are running a multi-phase commercial pilot with FedEx and PACCAR that launched during the Q3 of last year.
Our pilot with FedEx uses Aurora-powered Peterbilt trucks to autonomously haul FedEx loads between Dallas and Houston, which is a 500mi round trip. This is an industry-first collaboration between an autonomous technology developer, a logistics provider, and a truck manufacturer. During the Q4 , we launched our second multi-phase commercial pilot with Uber Freight. We're autonomously hauling loads for Uber Freight's customers, and we are also working with them to explore integrating access to their digital freight network with Aurora Horizon, our autonomous trucking product. We see this as an exciting opportunity to provide carriers with an additional set of tools to maximize the utilization of their Aurora-powered trucks, broaden opportunities to haul goods, and streamline supply chain operations. During the Q4 , we began pulling loads for our partners five days a week.
In January, we started nighttime hauls, demonstrating the Aurora Driver's capability of operating day and night and further increasing our opportunity to learn. Texas is an important testing ground for us. It is the largest trucking market in the country, with more goods hauled by trucks than in any other state, and the freight moved on Texas highways is expected to nearly double in the next 25 years. Today, we are announcing that trucks powered by the Aurora Driver are now regularly driving between Fort Worth and El Paso in preparation for an anticipated new upcoming pilot launch. This lane represents the middle leg of one of the busiest commercial thoroughfares in the US trucking industry, Atlanta to Los Angeles. The Fort Worth to El Paso lane is over 600 mi and takes approximately nine hours to complete.
Its long distance and monotony contribute to this lane's reputation for being undesirable for truck drivers. By deploying the Aurora Driver on such demanding hauls, we are building toward a future in which autonomous trucks can handle long routes while human drivers can handle more convenient hauls that are conducive to more desirable lifestyles. In addition to our pilots, earlier this week, we announced a collaboration with US Xpress. Through our collaboration, we intended to leverage the intelligence of Variant, US Xpress's digitally enabled fleet, to identify where our autonomous technology can have the greatest impact in terms of both addressing unmet demand and improving operational efficiency and productivity. Together, we have also committed to exploring how autonomous technology can create a positive impact on the labor market by investing in programs to provide opportunities for new jobs.
To recap, we are currently engaged with the largest LTL freight carrier in the United States, a significant freight broker, and now a large and technology-forward truckload carrier, gaining distinct and important knowledge from each. As we continue to engage with these partners and other carriers, we have begun the first phase of the Aurora Horizon subscription reservation process. We have received initial non-binding indications of interest that exceed our anticipated launch fleet capacity through 2025, underscoring the strong underlying demand for our autonomous trucking solution. We believe our collaborative and pragmatic process will provide important insights into customer demand, inform our trucking lane expansion plan, and ultimately support the optimization of our final subscription allocations.
As we continue to learn, increase our operational capabilities, expand into new operational design domains, and formulate our trucking launch plan, we are also making exciting progress developing Aurora-powered vehicles with our vehicle partners. In the North American freight space, we partner with PACCAR and Volvo Trucks, two of the top three trucking OEMs, who together make up nearly half of the market. They're both premium brands, and they're just incredible partners to work with. These are, again, amazing companies, and we've made tremendous strides with both. Through our work with them, we have continued to invest in our autonomous fleet, which now comprises 18 trucks, more than double the size of our operational fleet we had in the Q4 .
Expanding our fleet allows us to test and develop our technical and operational capabilities at large scales while we continue to form the vast majority of our testing using virtual development tools. We're also thrilled to work with Toyota on their vision for mobility for all, bringing self-driving vehicles to market. Through our long-term collaboration, we are laying the groundwork for the mass production, launch, and support of autonomous passenger vehicles on ride-hailing networks, including Uber's. We're able to work towards the launch of both our trucking and ride-hailing businesses with our partners because of our common core technology in the Aurora Driver. When I say common core, I mean that the Aurora Driver's hardware, software, infrastructure, and development tools are designed to work across vehicle types. This commonality ensures that lessons learned, development efforts, hardware improvements, and cost reductions made to the Aurora Driver benefit every vehicle it powers.
As we make progress on the trucking front, we're also forging ahead with both our development and commercial milestones on Aurora Connect, our planned product to serve the ride-hailing space. At the end of the Q1 , we expect to launch the Aurora Driver Beta 2.0, not only on the next generation of Aurora Driver-powered trucks, but also on the next generation of our passenger vehicle fleet, the Aurora Driver-powered Toyota Siennas, that will ultimately support the launch of our product for ride hailing. Achievement of this important milestone will demonstrate one of our key competitive advantages, the transferability of our common core technology. Notably, the Aurora Driver Beta 2.0 powered truck and Sienna fleets are targeted to launch with the same expanse and maturity. Aurora's product roadmap is designed to deliver the Aurora Driver at a large commercial scale.
With each quarterly product release, Aurora plans to deliver an Aurora Driver that's incrementally advancing on two axes, expanse and maturity. Expanse represents the breadth of capabilities and domains in which the Aurora Driver can operate. For example, training the Aurora Driver to handle different types of construction on highways, dense suburban settings, and ultimately dense urban environments are increasing the driver's expanse. Maturity represents the degree to which capabilities are ready for commercial deployment and will evolve from development to validation to completion. Maturity will be exemplified through longer durations of commercially representative autonomous operation with a safety case that supports it. A critical milestone we expect to achieve in the Q3 of this year is the Aurora Driver's ability to safely pull over to the shoulder without the help of a vehicle operator.
When we look at the key capabilities necessary to safely operate a vehicle at highway speeds, it is critical that the vehicle can safely handle possible system failures. We believe this milestone will demonstrate the maturity of the Aurora Driver and our progress towards satisfying the fail-safe core claim of our safety case framework. In the slide deck, we've included a video of our initial development and virtual testing of this capability. You'll see that we are able to bring the vehicle safely to the shoulder of the road and stop. We're now expanding our development and testing to mature the capability to be able to handle more complex scenarios, like avoiding other vehicles stopped on the shoulder.
We are working to ensure the Aurora Driver's capabilities address varied road environments like highway, suburban, and urban roads, changing lighting conditions like day, night, dawn, and dusk, a myriad of weather conditions, including clear skies, fog, rain, and snow, and different types of construction and responding to system failures. A great example that we include in our slide deck is a video of the Aurora Driver operating autonomously in a monsoon rainstorm in Texas. This is an incredibly challenging scene. There's a lot of rain in the camera lens, there's water being thrown up on the road, and there's heavy rain in the air. Despite all of this, the Aurora Driver is able to reliably see other vehicles on the road and drive safely, even as people are pulling off to stop. As you can imagine, making our technology work reliably is incredibly challenging.
Not only as Aurora's CEO, but also as a roboticist and engineer, it's incredibly exciting to see the strides we're making with our technical progress. As I mentioned when we started Aurora, we believe that one of the most critical steps for building technology to transform an industry like transportation was to invest in the foundational elements to both accelerate development and enable scalability. One example of where we've done this is with our proprietary FirstLight Lidar with frequency modulated continuous wave technology, known as FMCW. This novel measurement technology allows us to see further than conventional pulse lidar technologies and instantly measure the speed of things moving through the world. Our FirstLight Lidar has unlocked our ability to deploy our products at highway speeds, where even fractions of a second can affect a vehicle's ability to react to unexpected obstacles.
When it comes to sensors, there has been some debate in the industry around the right approach. At Aurora, we feel strongly there is only one right approach, a multimodal sensor system that enables our vehicles to get the richest set of data to perceive the world around them. With that, our world-class hardware team has designed and built a multimodal sensing suite comprised of FirstLight Lidar and other lidars, as well as powerful cameras and radars that optimizes range, field of view, data quality, and data processing efficiency. In the spirit of continuous improvement, we are always considering ways to further enhance our hardware stack. We have hypothesized that our FMCW technology may also deliver advantages in mid-range distances. We have recently tested this hypothesis and observed that FirstLight Lidar demonstrates superior probability of detection of dark targets relative to commercially available mid-range lidar.
With FMCW technology, we also get the additional benefit of simultaneously returning velocity measurements at these mid-range distances that traditional lidar can't provide. This analysis is ongoing and will inform the architecture of the lidar component of our future hardware generations. In terms of testing our hardware and software stack, there is a limit to how much meaningful data can be efficiently gathered from on-road driving. We've also invested heavily in the development of proprietary, high accuracy, and scalable virtual testing technology. In our virtual testing suite, we've built proprietary technology that allows us to accurately model how energy and light moves through the world. This allows us to build physically accurate sensor simulations for cameras, conventional lidar, and of course, for our proprietary FirstLight Lidars.
We've also built a procedural generation framework that allows us to create a basic scene and then create complex variations on that scene. This becomes particularly important when we are testing scenarios that are too rare or dangerous to test in the physical world. We continue to accelerate our development and validation through simulation and virtual environments, testing at scale and cost we couldn't achieve in the physical world. We believe our virtual testing is the quickest and safest way to train, test, and ready our self-driving technology for deployment at commercial scale. In the slide deck, we included a video of a new capability, nudging for debris in the roadway, that we have been developing and testing in simulation. While vehicles can run over small obstacles in the road, for obvious reasons, they should avoid larger pieces of debris.
This video shows that the Aurora Driver was capable to detect an object at a far enough distance to gracefully move out of lane to avoid it. We're incredibly proud of the technical progress we continue to make and look forward to sharing more on this front. Another important part of bringing this technology to market is educating our various stakeholders on Aurora's approach to development and deployment, as well as the far-reaching benefits self-driving technology can provide.
Earlier this month, Aurora had the honor to be the only autonomous vehicle company asked by Congress to present at the House Committee on Transportation and Infrastructure hearing on automated vehicles. This was an incredible opportunity to show our leadership on safety and a great example of how we work collaboratively with legislators at the federal, state, and local levels, as well with regulators, safety advocacy groups, and other self-driving companies to bring safe and innovative technology solutions to market. We're committed to being transparent with our work and our progress to help bring the government and public along on the self-driving journey. As we wrap up our first business update as a public company, I'd like to reflect for a moment.
Building a great company and technology to transform transportation means not only making tremendous progress technologically, but also demonstrating the societal and economic benefits self-driving technology can provide. On that note, I want to reference the principles for transportation innovation released recently by the Department of Transportation and Secretary Pete Buttigieg. As he mentioned, innovative technology is not an end to itself, but is meant to serve the public and society. We couldn't agree more. We're building the Aurora Driver to save lives, increase access to transportation, and support and improve supply chains. As a public company, we are proud to have our investors on this journey as we work towards building and delivering a commercial self-driving product at scale. I will now pass it over to our CFO, Richard Tame, who will share more about our financial results.
Thank you, Chris. 2021 was a capstone year financially for Aurora. As Chris mentioned, to kick off the year, we acquired ATG, Uber's self-driving vehicle business, which further bolstered our technology stack and gave us the depth and breadth of talent to better tackle the complex challenge of developing a scalable self-driving product. As part of this transaction, we received $400 million to capitalize the combined company. This transaction also had a one-time impact on our reported stock-based compensation that I will review in a moment. During 2021, we had $83 million in collaboration revenue for development work on the Sienna platform associated with our agreement with Toyota. This work will ultimately support the launch of our product for the ride-hailing space.
As a reminder, this collaboration revenue is recognized using the input measure of hours expended as a percentage of total estimated hours to complete the project. Operating expenses, including stock-based compensation, totaled $813 million. Excluding both ongoing and acquisition-related stock-based compensation of $92 million and $128 million respectively, operating expenses totaled $593 million. Within operating expenses, R&D expenses, excluding $206 million in stock-based compensation, totaled $491 million, primarily comprised of personnel costs as we continue to invest in our industry-leading autonomy work. SG&A expenses, excluding $13 million in stock-based compensation, were $102 million, which included costs associated with building our public company infrastructure.
There are two items I wanna flag on stock-based compensation, which are reflected in the reconciliation that we provided in the non-GAAP financials in the shareholder letter that we have posted to our investor relations website and furnished with our Form 8-K filed today with the SEC. First, on a full year basis, $128 million of the $220 million stock-based compensation presented is one-time in nature, related to our acquisition of ATG in January 2021. Prior to the acquisition, employees of ATG received RSU grants in Uber, the former parent company of ATG, who based on their investment in Aurora, is considered a related party following the closing of the transaction. While these are not Aurora awards, given the related party characterization, they are accounted for as a stock-based compensation on our books.
Second, when looking at the Q4 of 2021 specifically, in addition to $30 million for related party awards, you will also see a $47 million catch up in stock-based compensation expense for Aurora awards that had previously satisfied time-based vesting requirements but also had a liquidity event performance condition for full vesting. This performance condition was met with the closing of the business combination that took Aurora public in November. Another accounting nuance related to our business combination to be aware of is the treatment of the public and private placement warrants, as well as the sponsor earn-out shares. These financial instruments are classified as derivative liabilities measured at fair value with changes in fair value reported each period. We recorded $20 million in non-cash expense during the Q4 to reflect the associated change in fair value.
Turning to cash flow. In 2021, we had $563 million in operating cash spend and $48 million in capital expenditures, the latter primarily reflecting investments in our facilities, IT, and other infrastructure. We closed our business combination taking Aurora public in November with $1.8 billion in gross proceeds and cash on hand, which we expect to fund Aurora through the commercial launch of our trucking product, Aurora Horizon, and into 2024. We ended 2021 with a very strong balance sheet, including $1.6 billion in cash, enabling us to continue to execute our mission of delivering the benefits of self-driving technology safely, quickly, and broadly.
Going forward, our intention is to provide a fulsome financial review like this one on an annual basis on our Q4 and full year business review calls as we encourage the investment community to consider our results on an annual basis, consistent with the long-term approach we take to executing on our mission and working toward delivering a commercial product at scale. With that, we'll now open the call to Q&A.
Thank you. At this time, we will be conducting a question and answer session. If you'd like to ask a question, please press star one on your telephone keypad. A confirmation tone will indicate your line is in the question queue. You may press star two if you'd like to remove your question from the queue. For participants using speaker equipment, it may be necessary to pick up your headset before pressing the star keys. Our first question comes from the line of Steven Fox with Fox Advisors. Please proceed with your question.
Hi. Good afternoon. Congratulations on all you accomplished this year. Chris, I was wondering if you could maybe talk a little bit about digitally enabled fleets. You had the announcement this past week, and you at the Uber meeting last week, Uber Freight highlighted some of the hopes for economy. How do those opportunities do you think differ in timewise and revenue-wise for Aurora versus, say, traditional methods of trucking? I had a follow-up.
No, thank you, Steven. Appreciate the question. As we think about this, what we're trying to do over this pilot period and exploration period with our partners is understand the unique needs of each of the different segments of the freight space. We're really excited to have the partnerships with US Xpress, with Uber Freight, with FedEx, and we look forward to learning from them as we move forward. We're excited about the technologies that US Xpress is bringing to bear through Variant. W e look forward to offering their customers and other customers the benefit of the understanding we get through that.
Great. I appreciate that. In terms of just some maybe checks we should be looking for in terms of progress this year, you did mention demoing the fail-safe on roads later I guess sometime this year. Can you just talk about what you have to do to get from where you currently are with doing that in the cloud and online to doing it on the open road?
We're excited about the things we have in front of us this year. At the end of Q1, we anticipate showcasing the transferability. This is one of the core architectural choices we made with the Aurora Driver, enabling it to operate both trucks and light vehicles. In Q3, we anticipate showcasing one of these very important elements of bringing the vehicle to a safe stop. W e've shared our safety case framework and one element of that is fail-safety. Part of that is being able to understand when to trigger and then actually having the capability on the vehicle to bring it to a stop. This is a significant milestone, in the development of it. Today, we're running this in simulation.
We're doing early work on vehicles in closed test courses. Between now and the time where we're gonna showcase this on public roads, we'll be continuing to advance that capability, enhancing the fault detection capability we have on board the vehicle to more handle a more large, broad set of problems that might occur at some point in the future so that we can operate safely.
Great. That's helpful. I'll drop back in the queue. Thanks.
Thank you.
Our next question comes from the line of Tom White with D.A. Davidson. Please proceed with your question.
Great. Thanks, guys. Congrats on your first public company earnings call. I guess we'll have to wait 12 months for the next one of these, it sounds like, though. Two, if I may. Chris, you talked about, some of the different kind of milestones and markers of progress here over the next several months. I'd be curious to hear your updated thoughts on the usefulness of metrics, for investors, like things like real-world miles driven or maybe miles driven without a human intervention.
D o you think those are useful things for investors to try and track or, do you guys anticipate maybe at any point in the future, kind of, publishing sort of a regular metric? Then could you just double-click on the comments around the non-binding indications of interest? I'm just curious, has the pace of that really picked up in in recent months or has it been kinda healthy all along? Curious whether, it might cause you guys to increase your pace of investment or the urgency of investment to, make sure that you take advantage of all that interest. Thanks.
Sure. I can just speak, so on the timing of calls, we do anticipate providing more regular, roughly quarterly updates on the business. I think the depth of the financial disclosures is where we intend to do that on an annual basis. Have no fear, we look forward to engaging more often than once a year. We think we're making exciting progress, and we look forward to the opportunity to share that with anyone who joins us. On the metrics front, there's a lot to unpack there. As we think about metrics, we continue to think that the disengagement report work that's put out there is, as many people not just us believe, just not a super useful indication.
As we've shared repeatedly, we think there's an immense amount of value in simulation. We leverage that dramatically, and we do orders of magnitude more testing and simulation than we would do on physical road because it allows us to do much more focused testing, it allows us to do more efficient testing, and it allows us to test things that we just wouldn't encounter by just operating trucks out on the public roads. That can give us more confidence in the ultimate safety of our vehicle. We've heard the investment community around the need to provide progress and metrics of progress, and we're continuing to try to find a good way to express that.
We think there's something around the way we talk about the maturity of the product and look for us to try and share more of that in the near future. Stay tuned, on that one. On the non-binding intent. We've tried to take a very collaborative approach to engaging with partners and customers in this space. Instead of going out to them and trying to beat them to shake loose their checkbooks, it's really about what can we do together to learn so that we can deliver a product that's of immense value to them and ultimately to their customers.
The approach we've taken is a three-phase process where we begin engaging with partners and potential customers around indications of interest, and we're in that phase of the process right now. We expect later to shift to a conversation around initial allocations, and we'll do that collaboratively with our partners, and that will start to be more firm, and then ultimately we'll get to final allocations. What we've heard from our partners is they really appreciate the transparency of the engagement we've had with them around this. We're very excited for that. As I indicated, we have, at this point, initial indications of interest exceeding our ability to deliver through 2025.
We're really proud of that, and I think it speaks a lot to the work our team is doing in both developing the technology but also building the relationships with these key customers in different segments of the freight space. Does it mean that we will want to accelerate investment to kinda keep pace with demand? We're still assessing that, and of course, we'll share more as we move forward.
Great. Thanks, guys.
Thank you, Tom.
As a reminder, if you'd like to ask a question, please press star one on your telephone keypad. Our next question comes from the line of David Vernon with Bernstein. Please proceed with your question.
Hey, good afternoon, and thanks for taking the time. Chris, I want to understand or get your updated thoughts on your expectations for when, in a particular use case, like for example, FedEx, where you're running between El Paso and Dallas, when you might be able to be taking some of the support capabilities of the safety driver and safety engineer, that kind of stuff, out of the truck. I'm just trying to think from a big picture standpoint, how is your thinking on the timing of when you might be able to validate the technology without a driver in the cab changing right now?
Yeah. We continue to work towards a commercial launch of the trucking product at the end of 2023, and we're excited about the progress towards that. Our philosophy on this really is one of continuous advancement and that at any given moment, there's a duration of which the vehicle could operate without oversight. Until we get to the point where it's continuously viable and doable in a commercially relevant way, it feels like it just doesn't make a lot of sense, right? If we have to operate our trucks with, three, five other vehicles surrounding them to be able to do it safely, it's just distracting from the core objective of addressing these increasingly rare events that hold up operation.
Until we're ready to do that and meet that acceptably safe bar, it feels like the most practical, efficient, and safe way to do the development and testing is to have an operator in the vehicle instead of five of them strewn about the highway around the vehicle.
Okay. It sounds like the 2023 is still what you're looking for there. Then maybe as a follow-up, Richard, could you help us understand the clean cash burn rate? I'm not sure if the stock-based comp charges that you had for the Uber stuff would have affected the underlying cash burn rate in 4Q. Can you give us a sense for where you intend to be exiting fiscal 2022 at? I'm just trying to get a sense for what we should be expecting in terms of cash burn for 2022.
Sure. I think to the second point first, that we don't think as a pre-revenue company that it's meaningful to provide the forward-looking guidance. We won't speak to that. The cash flow is relatively clean from the Uber RSU perspective. That obviously shows up in the non-GAAP reconciliation for stock-based compensation there. I think we had $563 million of operating cash spend and $48 million on CapEx. That's basically clean cash flow for full year 2021. Then in Q4 . Just getting here. I think that's what we had, and we can follow up.
Okay. Yes.
[inaudible]
I appreciate the statement that you don't wanna give too much guidance right here, but if you were to think about it just directionally, are there investments in R&D and a step up in OpEx that we should be expecting that is gonna make that number get worse? Is it gonna get better? Just anything directionally, you can give us on that front would be helpful.
Yeah. I think the directional thing is that we have $1.6 billion of cash on the balance sheet at the end of the year. As we work towards launching the product at the end of 2023 in trucking, we feel like we've got enough cash we believe we can get through the commercialization and then into 2024.
All right. Thanks, guys.
Thank you.
Thank you. Ladies and gentlemen, we have reached the end of the question and answer session. This concludes today's conference, and you may disconnect your lines at this time. Thank you for your participation, and have a wonderful day.