Make
betterads

Understanding the advertisingindustry’s environmental impact
and what we can do to reduce it.

It’s time to cleanup (y)our ads
Everything generates emissions.
Yes, even your online activity.
According to the latest studies, the carbon
footprint of our gadgets, the internet andthe systems supporting them account for
approximately 2-4% of global greenhousegas emissions.
That’s almost double the airline industry.

Awareness of this hidden
footprint has been growing,
and the wider industry is
starting to take steps tocounteract it. And if you
can’t measure it, you can’t
manage it.

| Make better ads whitepaper 2023

Three things the digitaladvertising industry
can do today

Here’s ours.
Let’s see yours.

In three simple steps you can join
our mission to advocate for moretransparency, while reducing theenvironmental impact of yournext campaign.

We calculated the CO2 footprint of our ads. You’ll findCO2 emissions per impressions included as a standard
metric in all campaign reports.

83kg

CO2 emissions per
1,000,000 impressions

Transparency is key to driving the ad industry forward,so, here’s our full methodology on how we were measuring
and reporting the footprint of serving a digital ad, how wecalculated the footprint and what we’re doing to improve it.

1
Ask publishers
to provide
emissions per
impression

2

3
Optimizead spend withhigher-quality
publishers

Cut complexity
and improvetransparencyof supply chain

1

Contents

01

Introduction - it’s time
to clean up (y)our ads [p3]06

What we learned from mapping
our digital supply chain [p18]02

Advertising’s hidden footprint [p6]07

Closing the gaps aka
our to-do-list [p22]03

WeTransfer Advertising [p9]08

Looking ahead [p27]09

How we got our numbers: summaryof methodology, scope and digital
supply chain [p29]10

Appendix [p34]04
05

The CO2 footprintof a WeTransfer ad [p12]
How we went about measuring theemissions of a WeTransfer ad [p15]Mapping our digital supply
chain: meet DIMPACT [p16]
Paving the way towards
transparceny and action:
meet The Carbon Trust [p16]CO2 emissions per impressions
measurements notations [p35]Full methodology [p36]Core definitions [p47]| Make better ads whitepaper 2023

2

01

It’s time to cleanup (y)our ads
How digital campaigns can be creatively
designed and executed through anenvironmental impact lens

| Make better ads whitepaper 2023

3

01 - It’s time to clean up (y)our ads

Introduction

Being online, like most things, generates emissions. In fact,
the latest studies estimate that the carbon footprint of ourgadgets, the internet and the systems supporting themaccount for 2-4% of global greenhouse gas emissions. That’s
almost double the airline industry.
The good news is that awareness of this hidden footprint
is growing, and the wider industry (including major brands
and media buyers) is taking steps to counteract it.

This is why we worked with DIMPACT to calculate the CO2
footprint of our wallpapers and include it in all campaign
reports. We also worked with the Carbon Trust to identify
ways to address roadblocks in measuring emissions fromdigital ads, and the action needed to provide advertiserswith the right information to reduce these emissions. We’recommitted to creating real change, and these partners
help us (and you!) to do what it takes to plan and optimize
campaigns with the environment in mind.

The not-so-good news? There’s little transparency fromdigital media owners on campaign emissions. And, if you
can’t measure it, you can’t manage it.

With this knowledge to share, we’ve signed on to workwith our clients and the rest of the industry to understandand address the footprint of digital ads.

WeTransfer has already started the journey to understandmore about our digital footprint and contribute ourown industry research to the matter. We’re on a mission
to reduce our carbon footprint by 30% by 2025, and arefocusing on measuring more, getting better data andengaging with suppliers to get better insights into ouremissions.

It’s just one of the ways we think about our environmental
impact. We were born with the idea of making ads that help
shape a better future for the advertising industry and we’reserious about taking action to reduce its impact as a whole,
not just within the walls of our offices.

It’s becoming clear that the carbon footprint of various media
distribution options is gaining significance, and will play anincreasingly important role in shaping where media budgets
are invested. It’s expected that this will become more urgent
as brands need to deliver on absolute emissions reductions
and net-zero pledges.

| Make better ads whitepaper 2023

We can work together to shape it, and help move the industry
forward. From our clients, partners, our data center providers,
ad tech partners and all of our employees, reducing theimpact of digital advertising on the environment is a win-win
for everyone.

4

01 - It’s time to clean up (y)our ads

In this whitepaper,
we hope to...

Share insights on thedigital advertising’s carbon
footprint that will spur media
platforms, media holding
companies, brands and ourpartners to take action.

| Make better ads whitepaper 2023

Take a step beyond thecurrent industry knowledge
and actively tackle theroadblocks to accurately
measuring ad emissions
so that advertisers haveeverything they need toreduce theirs.

502Advertising’s
hidden footprint
The race against the emissions
clock as digitalization grows| Make better ads whitepaper 2023

6

02 | Advertising’s hidden footprint

As more and more
people come online,
emissions willcontinue to growHow can digital ads create greenhouse gas emissions?
When it comes to online advertising sharing data, powering
data centers and device usage all create emissions.
In the milliseconds it takes for an ad to pop up on a webpage,
many companies like ad agencies, data platforms, and ad
servers are in a fast-paced bidding contest. They’re all vying
for the chance to display an ad to a particular group.
It’s a rapid digital competition behind the scenes, making
sure the right ads reach the right audience. All this requires
energy, which creates emissions.
As more and more people come online, emissions willcontinue to grow. We’re more online than ever and internet
traffic is expected to grow 40% per year. That’s a 40x
increase by 2030.
Based on the most widely referenced data, the average
digital ad campaign can produce around 5.4 tons of CO2
emissions. The longer and more intricate the journey fromthe server to the user’s devices, the bigger the energy
consumption and emissions. This number will evolve as
we understand more about the supply chain, but it’s stilla reminder that the efficiency of the ad supply chain plays
a significant role in environmental impact.

| Make better ads whitepaper 2023

Recently, individual advertisers, holding companies,
creative agencies, industry associations, and collaborative
working groups have begun to acknowledge the impact,
have made dedicated commitments to shrink their carbon
footprint or generously shared valuable resources tohelp others do the same. Coalitions, like Ad Net Zero,are committing to real practical changes as a way
towards net zero by the end of 2030.
A recent study by the IAB found that over half of digitaladvertising companies don’t measure emissions. This
inaction can in part be attributed to the lack of availability
and transparency around emissions data.
Sustainability practices are urgent, and they are also
beginning to be a legal requirement. Under strengthening
EU initiatives, many companies will have to measure andreport their Scope 1, 2 and 3 emissions.

7

02 | Advertising’s hidden footprint

Three things the digitaladvertising industry
can do today
In three simple steps you canjoin our mission to advocate formore transparency, while reducing
the environmental impact of yournext campaign.

| Make better ads whitepaper 2023

1

2
Ask publishers to provide
emissions per impression

Not enough digital media owners offertransparency on campaign emissions. It’s only
when advertisers have the ability to compare thecarbon footprint of different media placementsthat they can make truly informed decisions andtake steps to reduce emissions in their media
strategies.
As an example, WeTransfer recently conducted
a comprehensive focus group initiative. We
brought together representatives from some of theworld’s largest media buying agencies, including
Essencemediacom, dentsu, UM, Havas, PHD,
mSix&Partners, and more. It was broadly agreed
that for a more conscious approach to media
planning, emissions per impressions needs to bea standard alongside all other campaign metrics,
not tagged on at the end.

Cut complexity and improvetransparency of supply chain

Action across the entire supply chain is critical,
timely and transparent vendor data are essential
to understanding the footprint of digital advertisingand actively addressing it.
Shorter supply chain means a smaller footprint.
The longer and more complex supply chain thatan ad has to travel from server to user devices, themore energy and emissions are created. Based ona recent study, a shorter supply chain with fewer
intermediaries, such as direct spend campaigns,
can produce around ~80% fewer emissions incomparison to programmatic.

3

Optimize ad spend withhigher-quality publishers

Digital ads with higher attention have been tied
to lower carbon emissions. Fewer ads on a site
is a better experience for the user. And fewer
ads mean less emissions and greater attention
on those that remain. It’s a win-win.

8

03

WeTransfer AdvertisingAward-winning ads people actually want to see| Make better ads whitepaper 2023

9

03 | WeTransfer AdvertisingThrough intuitive tools that get ideas
moving, and attention-grabbing ads thatpeople actually like, we connect andempower creator communities worldwide.
WeTransfer delivers quality reach at scale.
We engage 80M active users every monthin 190 countries. Founded BY creatives
FOR creatives, we have built a trusted andauthentic brand amongst the creative
community.
Whether it’s high-impact video or immersive
storytelling, we deliver to the people thatmatter. Through ads that are both beautiful
and appealing yet non-intrusive, ouradvertising supports the creative flow, rather
than distracting from it. Our full-screen
format allows us to create clean, immersive
advertising with the focus on a single
message.

Rest easy on what surrounds your ad
with our brand safety policies. 100% shareof voice, and over 30% of our ad inventory
worldwide to showcase diverse creative
voices and causes we care about.
You advertise, we support. 1% of allrevenue goes to WeTransfer’s Supporting
Act Foundation, providing a helping hand to
emerging artists and community-centeredinitiatives—ensuring they have the resources
they need to create long-term, systemicchange.
Your brand achieves the highest
standard of accessibility throughuser-centric design. We keep the diversity
and uniqueness of our audience in mind
by ensuring our advertising content isreadable on a wide range of screen sizes,
is appropriate for all ages, and is accessible
for all.

WeTransfer’s entire approach toadvertising is underpinned by ourcommitment to responsibility.
As a B Corp, your brand is safe with us.
So what’s a B Corp anyway?
B Corps are companies that harness the powerof business growth to make a positive impact on
the world —balancing people, planet, and profit.
Think Aveda, Allbirds, Chloè, Warby Parker, Ben& Jerry’s, and WeTransfer. Learn more and checkout our Impact Score.

Actively working to reduce the footprintof (y)our ads. We’re climate neutral certified,backed by our science based climate goals,
and are on track to reduce our carbon
footprint by 30% by 2025.

Ad example to go here
| Make better ads whitepaper 2023

10

03 | WeTransfer Advertising

When hearing the term ‘digitaladvertising,’ WeTransfer users
are more likely to experience
positive emotions1:
51% | 150 Index ‘Excited’
53% | 143 Index ‘Connected’
46% | 184 Index ‘Happy’
45% | 141 Index ‘Entertained’
43% | 187 Index ‘Trustful’
39% | 134 Index ‘Purposeful’57% | 133 Index WeTransfer
users are more likely to be purpose
driven “Premium advertising should
allow me to be part of something bigger/ contribute to a greater cause”1
1

WeTransfer Digital Premium Advertising Survey, Suzy, 2023 an index above
100 means that WeTransfer users are more likely to exhibit this particular
trait. An index of 150 means users are 50% more likely to connect “excited”
to “digital advertising” compared to non-users of WeTransfer.

| Make better ads whitepaper 2023

More than 8 in 10 WeTransfer users
say: “I consider the advertising I see
on WeTransfer to be premium.”11

04

The CO2 footprintof a WeTransfer ad
100% share of page, better user
experience, less waste. Jackpot| Make better ads whitepaper 2023

12

02 | The
04
Advertising’s
CO2 footprint
hiddenof footprinta WeTransfer ad

83kg*A small (yet important) noteThis figure was generated by
WeTransfer’s carbon footprint model,
and should be interpreted as an average
figure for ads served globally, using
WeTransfer data from 2022.
In the appendix, you’ll find more details
on how this metric should be used, ourmethodology, assumptions, and what
we’re doing to improve the measurement.
The Carbon Trust reviewed the model
to identify areas for improvement.

| Make better ads whitepaper 2023

CO2 emissions per*
1,000,000 impressions

It’s not just us, the industry wants
action, too. We spoke to some of theworld’s biggest media buyers, including
Essencemediacom, dentsu, UM, Havas,
PHD, and mSix&Partners among others.

“You can’t manage what
you can’t measure”“CO2 emissions per
impression needs to beup front with core campaign
measurement metrics:
effectiveness, conversion
and cost”

Measurement is key to improvement, and we
include campaign level carbon emission reports
as standard to support brands in measuring andaddressing the impact of digital ads.
The first step is to make sure all our clients arein-the-know about the emissions linked to theircampaigns. And, together, we can take the next
steps to meaningfully address it.

“Collaboration is criticalto success, and needs tocome ahead of competitionright now. We need to work
together to share solutions
and what works.”13

02 | Advertising’s hidden footprint

CO2

Emissions Report
Though we haven’t done a like-for-likecomparison with programmatic advertising,through mapping and measuring our digital
supply chain, we can confidently conclude
that our current direct approach to ads reduces
the need for additional server infrastructure,
reducing the complexity of the supply chain
and lowering emissions.

80% fewer
emissions generated
vs. programmatic
Estimated industry average*
514.8 grams C02 per 1000 programmatic ad impressions

1,000,000 impressions = 514 kg CO2
WeTransfer Advertising average

1,000,000 impressions = 83 kg CO2*Scope3 State of Sustainability Report - Q1 2023

| Make better ads whitepaper 2023

14

05

How we went aboutmeasuring the footprintof a WeTransfer ad
Working together to create an action plan

| Make better ads whitepaper 202315

05 | How we went about measuring the footprint of a WeTransfer ad

Mapping our digital supply
chain: meet DIMPACT
In 2022, we worked with DIMPACT to map our ad
infrastructure and calculate the emissions per impressionsof a WeTransfer ad (or wallpapers as we like to call them).
With these insights, we’re able to work with our advertisingclients and supply chain partners to understand andaddress the footprint of our ads.

Paving the way towards transparency
and action: meet The Carbon Trust
Once we’d mapped out our major sources of carbon
emissions, we joined forces with The Carbon Trust toevaluate the quality and credibility of our carbon footprinting
methodology and model. Our aim was to gain a deeper
insight into how we can reduce our advertising’s carbon
emissions, and ultimately support better decision making.
Working with The Carbon Trust was a critical step in building
a roadmap for the whole industry to improve the accuracyof measuring emissions from digital ads and providing
advertisers the information and tools that they need totake action to reduce theirs.

| Make better ads whitepaper 2023

As a DIMPACT member, we’re regularly engaging with theindustry on how to estimate and address emissions fromdigital ads. We presented our findings at London Tech Week
and contributed to research about possible solutions for the
Information, Communication and Technology (ICT) sector
to continue reducing energy consumption and carbon
emissions.

DIMPACT is a collaborative initiative between leading media,
entertainment and technology companies and world-class researchers.
Part tool and part community, DIMPACT has been developed with
cutting-edge expertise from computer scientists at the Universityof Bristol, and is convened and delivered by Carnstone, a sustainability
consultancy based in London.

The Carbon Trust crosses our Ts and dots our Is.
They review our measurement model and expertly
steer us down the right path when it comes to identifying
the ways we can reduce emissions.
This whitepaper is our flag in the sand. We want
to open up our discoveries to the industry, as partof our commitment to expanding collective knowledge
and action. Our goal is to break through existing barriers
and offer insights that go beyond current industry
knowledge. We’re focused on empowering advertiserswith the right information to take meaningful steps
in reducing their environmental impact.

The Carbon Trust is a global climate consultancy driven by the mission
to accelerate the move to a decarbonised future. Climate pioneers forover 20 years, it partners with businesses, governments and financial
institutions to drive positive climate action. From strategic planning andtarget setting to implementation and communication, the Carbon Trustturns ambition into impact. To date, its 400 experts have helped set over
200 science-based targets and guided more than 3,000 organizations
and cities across five continents on their route to Net Zero.

16

05 | How we went about measuring the footprint of a WeTransfer ad
View our full digital supply chain on page 37

Our digital
supply chain

Ad
Production

Final adcreativedeliveredAd
engineering

Key:
Emissions produced
as a result of activities%

Estimated % oflifecycle emissions

Operational energy consumptionof WeTransfer’s ad related teams
is calculated separately as part ofoverall business footprint (see ourlatest Responsible Business Report).

UploadedandstoredUploadedandstoredinto
data
centerinto
data
center1.2%
Partners that manage ad inventory,
performance and monitoring

WeTransfer ad
displayed onuser’s desktop
or laptop

In-homenetworking

DatacenterElectricity generated
to power user’s devices

Internet transmission via hometerminals and routers

Storage and Encoding+ Content Delivery Network (CDN)

32.7%

5.8%

59.7%

| Make better ads whitepaper 2023

Ad
management

0.6%

17

06

What we learned
from mapping ourdigital supply chain
Here’s ours. Let’s see yours| Make better ads whitepaper 202318

06 | What we learned from mapping our digital supply chain

1

From mapping our digital supply chain for
direct spend wallpapers, we’re able to seethat our advertising infrastructure is quite
efficient. With fewer partners involved
in serving ads, we’re reducing energy
consumption and emissions. Cool, eh? which we are confident reduces ‘waste’.

Here are the biggest hotspots
in our supply chain:In-home networking

User devices(routers/ Wifi / Fixed Line Internet)

32.7%
Ad engineering

1.2%

5.8%

Ad
management

0.6%

Data center

59.7%| Make better ads whitepaper 2023

It turns out that IT usage makes up a larger
portion of our overall emissions. It’s worth
noting that this includes all AWS processes
unrelated to ads, such as file transfers,
to be conservative in our measurement.
We’re looking into ways we can separate
these emissions from the emissions createdby the advertising infrastructure (that’s
covered in the gap analysis section).

Amazon Web Services (AWS), we’ve
found a like-minded ally ready to join
us on this journey.
In fact, we’ve already made the switch overto more efficient processors. Together with
Amazon Web Services (AWS) we’ve actively
looked for ways to optimize our server user
and continue to reduce the environmental
impact of our cloud storage.
We’ve also made it easier for organizations
looking to cut their own emissions from theirdata centers with the recently published
Doing Business Better — a toolkit with advice
and best practices.

Reducing the carbon footprint of ourdata handling starts with recognizing theenvironmental impact of digital infrastructure
in general. We’re all about exploring
innovative solutions in how we use thistechnology. In our partnership with19

06 | What we learned from mapping our digital supply chain2

Direct spend,
smaller footprint

Shorter supply chain means a smaller footprint. The longer
and more complex the supply chain that an ad has to travel frommultiple servers to user devices, the more energy and emissions
are created. Based on a recent study, a shorter supply chain withfewer intermediaries, such as a direct spend, can produce around~80% fewer emissions in comparison to programmatic
What’s the difference between direct spend supply chain
and auction based programmatic supply chain?
• A lot of media owners use one or even several Supply
Side Platforms (SSP) to generate ad revenue and placetargeted ads.
• These SSPs interact with demand side platforms (DSP)
that represent advertising clients.
• These two platforms are constantly communicating witheach other and bidding for ad space. More communication= more energy consumed and more emissions. Opting fora direct spend could lead to reductions all around.

3

There’s (more) work to be done to improve
the state of digital product footprinting

When we think of the cloud, we think ofsomething light and fluffy rather than thegigantic infrastructure, resources and energythat make being online possible. Digital
footprints are beginning to receive the sameawareness as physical footprints for products
and organizations.
Digital products and services have components
across multiple (often closed) systems, andeach needs its own energy and resource
requirements.
On top of that, the well-known cradle tograve/gate approaches of product carbon
footprinting are still evolving for digitalproducts. The typical life-cycle processes
aren’t necessarily fit for purpose when it
comes to digital products and services.
According to the GHG Protocol Scope 3
Standard, Use of Sold Products for a digital| Make better ads whitepaper 2023

product, which includes data transmission to
end-users, and the viewing devices themselves(for companies that don’t sell the device),
are an ‘optional’ category for a company like
WeTransfer. As an industry, we need action
and agreement on what the boundaries of the(embodied) emissions, energy and materials
required to deliver a digital ad.
So, where do we begin? Here’s a few
starter questions:• How much energy is needed to host a
product across servers, cloud containers,
and content delivery networks?
• How does an organization measure howmuch energy is needed for users to use theirproduct or service over time? (Especiallyacross different devices).
• What does ‘end-of-life’ measure, when
you can’t ‘dispose’ of a digital asset?

20

06 | What we learned from mapping our digital supply chain

4Standardization and transparency
are (still) a challenge

We know how hard it is to measure the footprint of
an impression, without creating one more new format.
While this is our current approach, we support a common,
industry-wide methodology and shared parameters, to help
measure the carbon impact of media channels and formats
across markets.
We need an industry-wide measurement process that’stransparent and consistent in the way data is collected andcalculated. Which will avoid biasing towards specific channels,
formats, buying methods or reporting. By default, it’ll also
make it easier for media vendors to provide data along similar
specifications, and agencies will benefit from a consistent data
set when it comes to their bespoke planning tools.

| Make better ads whitepaper 2023

We need anindustry-widemeasurement
process that’stransparent andconsistent

21

07

Closing the gaps
aka our to-do list
As with most things in sustainability, it’s complex.
But we’re up for a challenge| Make better ads whitepaper 2023

22

07 | Closing the gaps aka our to-do list

Our mission was to provide the industry and our clientswith actionable steps to reduce carbon emissions from
WeTransfer campaigns. We want to make sure that any
changes we make are having a real-world net reductionof emissions, not just reduction in our carbon accounts.
When you’re thinking big like we are, it’s important to do
things properly. When it comes to sharing our findings withthe world, we want to consider the impact over the short,medium and long-term. While it might make sense to takethe quick route and prescribe immediate actions to move
emissions off our accounts, but not actually change much,
we believe that the long-term impact is what truly matters.
So, we’re taking a beat and to make sure we do it right.
We know there’s a lot more work to be done before we canprovide concrete solutions. The Carbon Trust has helped
us identify the challenges in delivering a real-world impact
in reducing emissions from digital advertising, which aresimilarly recognized by the broader industry.
Product Carbon Footprints (PCF) of products including
goods and service can vary, and are influenced by factors
like data quality, the boundary of the product being
assessed, and assumptions about how customers engage
with the product. It’s a reminder of the dynamic natureof sustainability metrics.

| Make better ads whitepaper 2023

Here are three factors
influencing the carbon
footprint of web-based
products and services:

1. Emissions from the generation of electricity thatis used to power data centers, networks and user
devices vary by region, depending on how electricity
is generated locally. For example, the majority of France’s
electricity is generated by nuclear energy while the US
relies on a mix of fossil fuel generation, renewables,
nuclear and hydropower. With this in mind, it is assumed
that emissions from serving an ad in France are lower
than serving an ad in the US.
2. How users access the digital content (such as the typeof device that they use), and whether the service they’reaccessing affects the energy consumption of that device.
3. How efficiently data centers operate - including theefficiency of the hardware and cooling infrastructure,
as well as the efficiency of the code running on thesedata centers and how well these factors are represented
in emissions reports provided to customers.
Understanding uncertainty in carbon footprints canbe a big challenge, but it’s a helpful one. It gives us a
more well-rounded view about how sensitive and varied
the results can be to different factors, such as the ones
listed above.

23

07 | Closing the gaps aka our to-do list

The Carbon Trust recommends
four actions to begin identifying
the levers to reduce emissions
from digital ads:

2

Cocreate a Product Category Rule (PCR) for moreconsistency and transparency across the industry

A PCR would act as a set of definitions
and guidelines the whole industry
could align on when it comes toreporting an ad’s environmental
impact. This could help the industryalign on important details like unitof analysis, allocation of rules anduse-phase rules.

1

Clear, transparent emissions
reports from data center providers

WeTransfer and DIMPACT should use industry connections to make a callfor a standardized approach to measuring and reporting emissions by data
center service providers. This includes convening a working group of data
center service providers, customers and GHG reporting practitioners toshare learnings, develop and publish best practices.

| Make better ads whitepaper 2023

Ultimately driving creator consistency
in a Product Carbon Footprint (PCF)
approach across the industry.
The outcome? A consistent approachthat empowers the industry toevaluate the environmental impactof ad with more clarity, allowing media
buyers to understand their impact,
so they can plan and optimize with theenvironment and performance in mind.

Even better, is that it can also be used
to better identify emission hotspots
and reduction opportunities within
supply chains.
In fact, other industries are alreadytaking the lead. Excel Dryer led aproject to develop a global PCR thatstandardized how the environmental
impact of hand dryers was measured.
It teamed up with industry leaders (andcompetitors) World Dryer and Fast Dry
to define standard industry metrics ofmeasuring dry time and energy use, sothat consumers could easily compare
similar products. With industry
consensus, every product is assessed
and reported in the exact same way,leveling the playing field24

07 | Closing the gaps aka our to-do list

3

Develop a collaborative product carbon
footprinting approach to identify carbon reduction
opportunities focused on the cause and effectrelationships across the digital advertising network

Understanding the carbon footprintof online products and services iscomplicated. They rely on a complex
network of data services that make it
hard to understand the exact cause
and effect of their emissions. In anutshell, it makes it trickier to clearly
identify the best opportunities toinfluence and reduce emissionsof the digital product.
Engaging academic researchers,
LCA practitioners and industry
groups to create an actionable andcredible industry roadmap will meanbetter industry decision-making on
how to reduce the impact of hosting,delivering and viewing digital ads.

where actions can have different
effects in the short and long term,and understanding these possible
outcomes is key to good decision
making in reducing carbon emissions
for online products and services.
For example, Fairphone’s recent
life cycle assessment proved thatkeeping a phone for at least five
years and replacing or repairing parts
significantly reduces its environmental
impact, as most emissions happen
during production. This makes it clear
to the smartphone industry (as well as
customers) where to focus investment
and future resources to have thebiggest influence on reducing theirimpact.

4

Evaluate the industry as a whole andits role on the path to net zero emissions

Even though calculating the impact
of digital ads is a work in progress, it’s
clear that the environmental impact ofhosting, delivering and viewing a digitalad is only a piece of the full advertising
ecosystem. To make real-worldchange, we need to look at how we
produce the ads, but also the products
we advertise and the environmental
impact they have.
Advertising has an important roleto play on the path to global net
zero emissions. It’s one of the bestcommunication tools we have, andwhen used properly and consistently,
has the power to inspire the world’s
most influential audiences towards
products, services and behaviors
that can reduce their impact on theenvironment.

The Carbon Trust points out ourachievements and ambitions to
use advertising as a force for good,such as bold advertising policies
and accessibility requirements, andprompts us to further explore how we
can inspire other industry peers to takecomprehensive climate action.
As we are actively engaged in ongoing
industry discussions related toadvertising, we can further explore
using our position to support client’s
advertising strategies in a way thatinspires them to take comprehensive
climate action.

Especially for systems as complex
as the internet and data networks,| Make better ads whitepaper 2023

25

07 | Closing the gaps aka our to-do list

WeTransfer
Advertising
policies

Respect consumers rights—not create
false expectations of an unhealthy lifestyle.
Comply with the law—all marketing communications
should be legal, decent, honest and truthful.
Promote conscious buying—it should not abuse thetrust of consumers or exploit their lack of experienceor knowledge.
Respect human dignity—it should not incite
or condone any form of discrimination, includingthat based upon ethnic or national origin, religion,
gender, age, disability or sexual orientation.
Prohibited categories—fossil fuel, fur, tobacco,gambling and gun companies are no-nos.

| Make better ads whitepaper 2023

26

08

Looking ahead
We’re motivated to inspire others
to join us on this journey| Make better ads whitepaper 2023

27

08 | Looking ahead

We’re committed to:

Increasing the accuracy of how wemeasure CO2 emissions per impressions
We’ll refine our carbon-counting strategy as estimating digital
and analogue carbon emissions improves. This means creating
unique measurements for the different ad types that we support,
including the country where the ad is shown to reflect theemissions factory of each country’s energy grid. We’ve outlined
these in more detail in the methodology section.

Driving more collaboration across thedigital supply chain means engaging every
client, partner, and platform that plays
a role in delivering a WeTransfer ad.
WeTransfer is already working hard to build valuable partnerships acrossvarious sectors. We’re teaming up with researchers, suppliers, technicalexperts, and customers to reduce emissions, pioneer new paths, craft
bespoke solutions, and spark inspiration. Our collaborative ethos is allabout empowering our partners to make measuring their footprint a toppriority and taking meaningful steps to reduce it. We’re in it for the long haul,
keeping the conversation going and sharing our knowledge across industry
groups like DIMPACT, Ad Net Zero, B Corp, Creatives for Climate, andLeaders for Climate Action.

| Make better ads whitepaper 2023

28

09

How we got our
numbers: summaryof methodology, scopeand digital supply chain
Find the full methodology in the appendix| Make better ads whitepaper 2023

29

09 | How we got our numbers

Transparency is key
to driving the media
industry forward

In digital advertising, collecting, measuring and reporting
data and CO2 emissions is relatively new. The lack ofa regulatory body and set measurement models is what
we believe is holding back the ability to analyze data andultimately, the full fledged adoption of reducing emissions.
Our journey involves heeding the wisdom of The Carbon
Trust’s Gap Analysis Key Findings. It’s rightly pointed outthat existing carbon accounting methods often fall shortin identifying the most impactful strategies to slashreal-world carbon emissions. WeTransfer is on board with
its recommendations, collaborating with the industry to
pinpoint these game-changing strategies. As detailed in
the Key Findings from the Gap Analysis, the Carbon Trustnotes that the current methodologies used in carbon
accounting do not provide a way to identify the mostappropriate leavers to support ensuring actions leadto real-world reductions in carbon emissions. WeTransfer
is following their recommendations to work with the industry
to correctly identify these levers.
Transparency is key to driving the media industry
forward, so, WeTransfer has published the methodology
we follow to measure and report the full climate impactof serving a wallpaper on wetransfer.com.

to align with the GHG Protocol Product Standard anddraws upon the GHG Protocol ICT Sector Guidance.
DIMPACT currently (by default) looks at use-phase emissions
only, not the ‘embodied emissions’ of things like servers anduser devices. This is because: (a) The data is more readily
available and generally higher-quality (but we plan
to work with data center partners to include this data intheir customer sustainability reports); (b) we understand that
embodied emissions of internet networks and user devices
are out of scope for WeTransfer when accounting for our
Scope 3 footprint.
This approach involves mapping the functional processes
in the delivery of digital media content (the processes
considered in-scope are outlined below) and thenparameterizing each of these processes.
Once WeTransfer identified the processes, we gathered andinput the necessary data for the DIMPACT Assessment tool.
WeTransfer commits to conducting an annual review at
the start of each calendar year, and we’ll complete a fresh
assessment to include the latest data.

The calculation of use-phase emissions per impressionof a wallpaper is based on the DIMPACT Methodology, using
an attributional life-cycle assessment approach, which aims

| Make better ads whitepaper 202330

09 | How we got our numbers

Outline of DIMPACT
Assessment Tool
DIMPACT offers typical ‘architecture diagrams’ that outline
the typical process for publishing - which serves as the scopeof the assessment. These diagrams serve as a checklist
for companies to compare against their own architecture,ensuring all relevant in-scope processes are accounted forin the calculation.
For each in-scope process within scope, DIMPACT supports
companies to engage with their service providers to gather
emission estimates through a standard data request form.
DIMPACT collects company-specific data on user behavior,including information on devices used, time spent, numberof sessions/impressions, and data volumes transferred.

| Make better ads whitepaper 2023

The DIMPACT tool also
provides default proxyvalues for estimation,
including:

1. Default values for user device
consumption (developed by the Universityof Bristol).
2. Default values for internet networking
intensity (both fixed and cellular, basedon academic studies).
3. Default values for Content Delivery
Network usage.
4. Once the data is entered into the DIMPACT
tool, the tool performs an assessment andgenerates figures for energy consumption
and CO2e (carbon dioxide equivalent).

31

09 | How we got our numbers

Mapping WeTransfer’s
digital supply chain
and boundaries

The major principles that defined the scopeof the boundary are:Emissions per impression
We’re all about shedding light on the environmental
footprint of delivering ads or campaigns to end users’
devices. Our mission? To empower our clients withinsights on how they can actively reduce emissions
from their digital ads. This could include aspects like
optimizing file sizes, making thoughtful choices between
direct and programmatic approaches, and keeping tabs
on trackers and more. As a proud climate-neutral certified
organization, WeTransfer takes the full responsibilityof calculating, measuring, and setting emissions reduction
targets for all our business operations. No need forour advertising clients to include these emissions fromour business operations as part of their campaign
emissions, we got it.
Partners in WeTransfer’s Digital Supply Chain
Now, let’s zoom in on our biggest partners within
WeTransfer’s digital supply chain who are key players
from the moment that final content gets uploaded until
it appears onto a user’s device screen. This is our chance
to join forces with these partners and make a dent
in emissions. We’ve already started sharing our bestsustainability practices, advocating for more transparency,
and championing standardization. As we continue on ourjourney, we will include more of our partners in the scopeof the assessment| Make better ads whitepaper 2023

Active View TimeAnd then, there’s the concept of “active viewing time.”
We’re not just looking at when users gaze upon an adon WeTransfer. We’re considering everything from datatransmission to server energy usage and even end-user
device power consumption until the user clicks on the
ad to a new page. When it’s not in the spotlight, we fairly
allocate the device’s energy consumption to the website
or app currently holding the user’s attention.
There are four main lifecycle stages: Production
Development Phase, Distribution and Storage Phase,
Network Transmission, and Consumer Use Phase. Eachstage represents a set of processes that in completiondeliver a digital ad to the end user’s device.
1. Production Development Phase• Begins with the final ad creative being packaged
and uploaded into Content Storage (known as S3
Content Storage).
2. Distribution and Storage Phase• Campaign metadata and configuration details, such as
target countries, number of impressions, and ad ranking,are sent for handling by the Ad Manager partner.
• Ad analytics tools provide WeTransfer with essential dataon page views, including percentages of views by country,
active time on the page, and impressions per page view.

32

09 | How we got our numbers• Engineering Analytics plays a crucial role inreal-time error reporting, performance monitoring,and observability stack management. It alerts theengineering team to critical availability issues.
• The majority of ad delivery occurs within WeTransfer’s
AWS infrastructure, where WeTransfer has control
over activities executed by AWS.
• The Ad Management utilizes auto-scaling Kubernetes
clusters to adapt server usage to traffic demands.
• Static assets are served through WeTransfer’s S3content delivery network (CDN).
• The AdSDK, a compact JavaScript bundle, is deployed
to the CDN and embedded in platforms where ads
are displayed.
• The AdSDK communicates with the AdProxy, whichis the backend of WeTransfer’s ad infrastructure.
• The AdProxy requests an ad from the Ad Management
system, which makes the decision on which ad todisplay.
• The AdSDK renders the ad, retrieving assets
from WeTransfer’s Ad Creative storage on S3.

| Make better ads whitepaper 2023

3. Network Transmission• The creative content departs from WeTransfer’s
servers and traverses a content delivery network
to enable faster loading by distributing static files
closer to the user’s location.
4. Consumer Use Phase

working hard to create separate measurements,
but for now, we’re taking a holistic approach andconsidering the entire server footprint including
file transfer and ad delivery.
For the nitty-gritty details about our scope and collection
data, check out the full methodology in the appendix.

• The final leg of the digital supply chain takes placeat the user’s end – their router bridges the gap, delivering
the internet connection needed to display the ad, whether
they’re on a desktop or laptop.
A Note on Boundaries: File Transfer as a Complementary
Product
The file transfer aspect is considered a complementary
product of delivering an ad impression on wetransfer.com,
for two reasons:
1. Initialization and Component Loading:
For that ad to render and count as an impression, ourTransfer App needs to jump into action, initialize itself,
and load all its components onto the webpage.
2. Server Emissions Integration:
Right now, measuring the energy and emissions
from AWS servers for both file transfer and ad delivery
separately isn’t as clear-cut as we’d like it to be. We’re

33

10

Appendix| Make better ads whitepaper 2023

34

10 | Appendix

Our notes
on measuring
CO2 emissions
per impressions

83kg

This metric represents an average value for ads shownworldwide, based on WeTransfer’s 2022 data. Currently,
WeTransfer uses a single measurement for all ad types.
We are actively working on improving it to better matchand measure the creative of each wallpaper. It’s the mostaccurate estimate based on the data available to us andthe wider industry. And what our clients can use to startbetter measuring and understanding their emissions.
WeTransfer is committed to improving the measurement,
as detailed in the methodology, and the calculations will be
adjusted as more accurate data becomes available. We’realso committed to doing our part in reducing emissions,removing greenhouse gasses, and encouraging our partners
in the supply chain to join us on this journey.

CO2 emissions per
1,000,000 impressions| Make better ads whitepaper 2023

The scientific community and industry has yet to reachbroad consensus measuring emissions from digital products
and services.
Right now, there’s a number of different data sources,
calculation methods, and media carbon calculators thatexist. Some of these methods are pretty high-level. They
estimate how much energy the whole internet uses, including
all your devices, in kilowatt-hours (kWh). They also estimate
how much data zips around the internet in gigabytes (GB).
Then, they
mash those numbers together to get a simple kWh per
GB ratio. But here’s the twist: it’s a bit of an oversimplification
because it doesn’t really capture the diversity of data center
workloads, the different types of ads, or the wide range of
devices in the digital world.
In the absence of standardization, things can get a bit tricky.
Inconsistent parameters make it hard to compare claims andmeasurements on an even playing field. We’re committed
to fostering collaboration that leads to a unified approachto carbon accounting and transparent calculation methods.
It’s our way of striving for a shared industry solution.

35

10 | Appendix

Full
Methodology

This is where we get into the fine details on how exactly
we calculate emissions per impressions. We cover how
WeTransfer collaborated with DIMPACT to leverage
its methodology (Version 1.0) and assessment tool, andmapped our digital supply chain to serve and develop ourown methodology for the calculation of an impression.
At a high level, DIMPACT is an initiative of media andtechnology companies that has come together tounderstand and measure the greenhouse gas (GHG)
emissions of serving digital media and entertainment
products. The initiative includes a web-based calculation
tool that allows participants to measure these emissions
using a standard Methodology.

Objectives of Study
The goal of this study is to calculate the CO2 emissions
per impression of an ad on wetransfer.com and provide
this information to WeTransfer’s advertising clients, enablingthem to understand, measure and address emissions fromtheir digital advertising campaigns. This information will help
clients make more informed decisions on indirect emissions
from advertising campaigns and address/reduce theirenvironmental impact.
Definition of Product
A WeTransfer ad is a creative image displayed on
wetransfer.com. This image is loaded when a user visits
wetransfer.com and the creative is held, then rotated,based on the media buy package.

It’s heavy stuff, but it’s important.
1. WHAT WETRANSFER IS DOING TO ADDRESSEMISSIONS FROM ITS DIGITAL ADS
WeTransfer is introducing CO2 emissions per impressionin all campaign reporting aimed at helping clients to measure
the emissions of their campaigns, report more accurately
on their carbon footprint, and identify reduction opportunities
in their digital media placements and campaigns.
The first step is making all clients aware of their emissions,so they are able to measure the footprint of campaigns
with WeTransfer. And, together, take the next steps tomeaningfully address it.

| Make better ads whitepaper 2023

For the purpose of this study a WeTransfer
ad is defined with the following attributes:• Average of all ad types: WeTransfer offers a rangeof ad types including static images, interactive hover,click to play videos, cinemagraph and games.
• Device types: laptop and desktop (with monitor)• Single measurement for all ads served globally• Future assessment will aim to provide measurements
based on the country that the ad is delivered in.

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10 | Appendix

Definition of Functional Unit
The functional unit is the service of hosting, delivery
and viewing of all advertising impressions globallyon WeTransfer.com in the calendar year 2022.
From this unit of analysis, we can calculate the average
emissions intensity estimate per 1,000 impressions.
Note that producing the creative assets for these
impressions is excluded from the boundary of this model.
For comparison, it is determined that the functional unitof the emissions from content creation would be: “Theemissions from producing the creative assets for a given
advertising campaign.” This is a different functional unit
to that outlined in this study.
It is also suspected that the emissions from creating
content will vary significantly depending on the choicesof the client when procuring an agency to create thecampaign. It is assumed that very few of these choices
would have an impact on the functional unit of this study.
The major principles that defined the scopeof the boundary are:
• The emissions per impression calculation is to provide
the client information on the emissions created in delivering
their ad/campaign to an end user’s device. The aim is tohighlight the areas where clients have influence in reducing| Make better ads whitepaper 2023

emissions in the digital supply chain, such as file size,
direct vs. programmatic, trackers and more. As aclimate neutral certified organization, WeTransfer takes
responsibility for calculating, measuring and setting/achieving emissions reduction targets for all activities
associated with business operations. WeTransfer
advertising clients are not responsible for addressingthese emissions as part of their campaign.

MAP OF DIGITAL SUPPLY CHAIN
There are four main lifecycle stages: Production
Development Phase, Distribution and Storage Phase,
Network Transmission, and Consumer Use Phase.
Each stage represents a set of processes that in completiondeliver a digital ad to the end user’s device.

• Map all the partners in WeTransfer’s digital supply
chain that play a significant role from final content
being uploaded to being displayed on a user’s device.
This provides an opportunity for WeTransfer to workwith our partners to reduce emissions, such as sharing
best practices and advocating for increased transparency
and standardization.
• Define the time that the user is viewing the ad on
WeTransfer. Data transmission, server energy usage
and end-user device power once the user clicks throughto the ad link. When not in the active view, the energy
consumption of the device would be allocated to thewebsite/application that is in active view.

The digital supply chain begins when the final ad creative
has been created, packaged and then uploaded into Content
Storage (named S3 Content Storage) and served through the
Cloud Front Content Delivery Network (CDN).
The campaign meta data and config such as target
countries, number of impressions and rank positioning(the order the ads are shown) are sent over to be handled
by the Ad Management Partner.

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10 | Appendix

Then the ad analytics tools provide WeTransfer with theinformation on page views including: % of views by country,
active time on page, impressions per page view.
Engineering Analytics runs real time error reporting,performance and monitoring. This is part of the observability
stack and alerts the engineering team to critical availability
issues.
The majority of the ad delivery happens within the AWS
infrastructure. WeTransfer has operational control over theactivities executed by AWS. The Ad Server is a mix of auto
scaling Kubernetes clusters that allows WeTransfer to scale
the server usage to the demands of the traffic.
We serve all static assets though our S3 content delivery
network (CDN). The AdSDK is a small JavaScript bundle
deployed to our CDN. This is embedded in any platform
where ads are shown. The AdSDK talks to our AdProxy,
which is the backend of the ads infrastructure. The AdProxyrequests an ad from the Ad Management system whichmakes the decision of which ad to show. The AdSDK renders
the ad, retrieving assets from our Ad Creative storage on S3.
The creative leaves WeTransfer’s servers and travels acrossa content delivery network that allows the ad to load fasterby spreading the static file delivery closer to where the user
is located.

| Make better ads whitepaper 2023

The user’s router provides the internet to display the ad on
the end user’s device (desktop or laptop). This is the final
stage of the digital supply chain to deliver an ad.
Note on Boundaries
File Transfer as separate (complementary) product
The file transfer aspect is considered a complementary
product of delivering an ad impression on wetransfer.com,
for two reasons:
1. For an ad to render and an impression to count,
Transfer App needs to initialize and load its components
into the page.
2. Currently, the amount of energy and emissions from AWS
servers associated with file transfer and delivering an ad
can not be measured separately. Therefore, WeTransfer
uses the entire footprint of the servers and is working on
creating separate measurements for file transfer and addelivery.
For this study, the emissions of anything related to filetransfer, upload, download and storage are not being
submitted for product carbon footprint verification or review.
2. REVIEW SCOPE AND COLLECT DATA FROM PARTNERSTO INPUT INTO DIMPACT ASSESSMENT TOOL
See Overview of Data Collection for details on data
sources, metrics, assumptions and areas of improvement.

Below is a list of the items and processes consideredin our emissions calculation for serving WeTransfer ads.
The digital supply chain to serve a WeTransfer
ad is defined with the following scope:• Data from January to December 2022
• Data Center (AWS) processes used to store,
serve and analyze ads (and file transfers)*• Including the Ad Decision Requests and emissions
from major partners involved in ad delivery, including
Ad Server and Ad Engineering• User engagement on the platform including numberof impressions per session, impressions by country
breakdown, and active time spent on site, provided
through Ad Analytics tools• Internet network transmission for delivering ad content
to users• An attribution of in-home networking, such as modem
routers) required for users to access ad content• Default countries in the tool are selected basedon existing DIMPACT users customer base
• Energy consumption of end-user desktop and laptop
devices whilst the ads are in active view
*AWS data includes all server usage (file storage, transfer and serving ads).
WeTransfer plans to improve this measurement by gathering emissions/energy consumption only for serving ads.

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10 | Appendix

Calculation does not include
As explained in the principles above, the following items
were excluded from the scope of the digital supply chain
to deliver an ad.
• Operational energy consumption of WeTransfer’s
ad related teams (e.g. offices, laptops, businesstravel, employee commuting)• Emissions associated with file transfer and other
WeTransfer services*• Emissions from ad production (e.g. shooting and editingof advertising media assets)• This was excluded as ad production has a different‘functional unit’ to the serving of these ads. For example,
ad production would not scale in the same way as theemissions from the impressions for viewing those ads.
• Data transmission, server energy usage and end-user
device power once the user clicks through to the ad link(which was deemed to be outside the boundaries of thisassessment)• Embodied emissions of servers, internet network
equipment and consumer devices. These were excluded
for the following reasons:• For servers and internet networking equipment,
the ICT Sector Guidance published life cycle life cycle
ratios (use-phase vs embodied emissions) of serverand network equipment.

| Make better ads whitepaper 2023

• For server equipment the use-phase madeup a significant proportion of the emissions(see Table A1.13 - Chapter 2).
• For servers, WeTransfer used primary data from theuse phase, which meant that data quality was high.
However, the providers of this data (AWS) did notinclude embodied emissions in their measurement.
Therefore these were excluded.
• For consumer devices, the GHG Protocol ICT Sector
Guidance, Chapter Six provides a detailed overview ofmeasuring the impacts of software (the most applicablechapter of this document). However, WeTransfer notesthat a discussion of allocating embodied emissions is
excluded from this chapter, and therefore assumes thatfor a software product, the embodied emissions should
be excluded. Through DIMPACT, WeTransfer will seek
clarity on the validity of this assumption, in order tounderstand if this should be included.
• Other minor suppliers to WeTransfer’s ad service, suchas analytics services (assumed to be computationallylight, therefore de minimis)• Energy consumption of end-user devices when WeTransfer
ads are not actively viewed(considered minimal, thoughfurther testing could confirm).

Cut-off criteria
This methodology aims for completeness. However,there may be instances where quantitative data are notavailable and where it is deemed that significant effort
is required to gather data that has an immaterial impact
on the product carbon footprint. In these instances,
WeTransfer has developed a cut-off criteria to determine
whether the process can be excluded:• Primary or secondary data, or usage data, is not available
for the process in question; and• An initial conservative estimation of the process suggeststhat excluding the process will have less than 2% impact
on the total expected footprint.
• The total estimated emissions processes that meet
the above “cut-off” criteria does not impact the overall
product footprint by over 5%.
For any processes excluded, this shall be included within
the footprint report, as well as the estimation method
documented. Note that this cut-off criteria differs fromthe system boundaries, such that the boundaries determine
whether the process is included in the footprint. The cut-off
criteria is used to determine whether in-scope processes
can be excluded based on the above.

• Energy consumption of ads on mobile and tablet devices,
as WeTransfer did not serve ads on these devices during
the reporting period. This will be reviewed in futureassessments, if this changes.

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10 | Appendix

3. INPUT DATA INTO DIMPACT ASSESSMENT TOOL
In order to convert the input data into the DIMPACT tool,
we have created an Excel tool that performs this operation.
This forms the ‘backup’ to the DIMPACT model runs, andshows the working behind the DIMPACT model inputs.
The metrics required to be converted from raw output
from WeTransfer’s internal systems included:• Total number of sessions• Average data volume per session (page view - as per
DIMPACT terminology)• This required WeTransfer to convert the impressions
per session numbers into average data volume perpage view• Impressions per session were very high, as ads
load even when the page is not in active view.
• The spreadsheet multiplies the number of impressions
per session by the average data volume per
impressions (source internally from WeTransfer),
to calculate the total data volume.
• Average emissions factors• The DIMPACT tool offers the input of emission factors
for selected countries (based on major markets where
DIMPACT participants have historically been placed).

| Make better ads whitepaper 2023

• Therefore WeTransfer needed to come up witha weighted average emissions factor to input into the‘Rest of the World’ entry field, as well as the percentage(%) of page views in each country, based on the
Ad Analytics data (discussed below).
• For this assessment, the International Energy Agency(IEA) emissions factors for 2022 were used. Note thatthese figures for 2022 are actually from 2020, due tothe lag in reporting. It is WeTransfer’s policy to use themost recent year of IEA data available. WeTransfer willcontinue to review available factors, in order to improve
temporal data quality in the future.
• Data volume per household• Data is required to allocate CPE (that’s carbon per
engagement) to a given service, based on data volume
per household per month.

• Ad Manager and Ad Engineering attribution• Covered in the section below.
In addition, the Excel tool to gather and document all data
inputs into the system. It was a handy reference point for
the assessment, offering insights outside of the tool itself.
4. RUN DIMPACT ASSESSMENT AND REVIEW RESULTS
Once the input data has been entered into DIMPACT, thetotal emissions for the reporting period is calculated. The
DIMPACT tool allows annotation of inputs, so that the
inputs can be traced to the Excel calculation. As a policy,
WeTransfer users must provide annotation to all inputs inthe DIMPACT tool.
This provides the total emissions for the reporting period.

• This data is only available for certain countries (youcan find the specifics in the DIMPACT Methodology
Appendix).

• The total emissions (location-based) estimate calculated• For places where this data isn’t readily available,
WeTransfer used an estimated weighted average.
This was based on the user profiles of our WeTransfer
community.

This makes it possible to understand the shareof emissions per impression, represented by storage,
uploading and downloading of data, the use of media
or the loading of an ad.

• Based on the total number of impressions40

10 | Appendix

OVERVIEW OF DATA COLLECTION PROVIDED
BY WETRANSFER, INCLUDING ESTIMATES AND
ASSUMPTIONS
Reference DIMPACT methodology for calculation
methodologies, emissions factor sources, justificationsof assumptions
WeTransfer reviewed the data fields in the DIMPACT
assessment tool, and collected/entered data for thefollowing fields. Additional calculations were carried out
in the Excel Sheet titled: DIMPACT - WeTransfer - Carnstone
Analysis - 2022 v2
DATA CENTER
Ad Management Services
Source: via AWS. Based on WeTransfer’s proportion ofpartner’s total Ad Decision Requests (ADR) over the year.
Logging and Monitoring Services
Source: Emissions from Ad Engineering partner. Primarydata was not available, so a spend-based method has
been used.
Other Services
Source: Emissions from AWS. This is placed in ‘otherservices’ as includes all WeTransfer processes that currently
can be broken down into the above data center processes.

| Make better ads whitepaper 2023

NETWORK INFRASTRUCTURE
Fixed Line Network
Source: Weighted average used, based on numberof impressions per country.
USER DEVICES
Customer Premises Networking
Source: Weighted average for impressions.
Computers
Source: Ad Analytics data.
Amazon Web Services (AWS)
Date range: January-December 2022
Data source: Primary - AWS’s
Customer Carbon Footprint tool
Key Metrics: CO2 emissions from
WeTransfer’s Cloud Workloads
AWS provide two key metrics as part of their emissions:• ‘AWS emissions’ for WeTransfer (including renewableenergy savings - ie market-based emissions)• ‘Emissions saved’ from AWS’s renewable energy (RE)sourcing• The above includes WeTransfer’s use of AWS’s content
delivery network (CDN)

Allocation approach and effect on interpretationof footprint results:• In this study, there is no disaggregation of ad delivery
vs. other file transfer services. The footprint provided by
AWS includes all WeTransfer workloads with AWS - notjust those required to serve ads. At this stage WeTransfer
doesn’t have a granular view of which workloads are forserving Ads, and which are for file transfer and other
WeTransfer features. Therefore, the emissions associatedwith serving an ad is very likely overestimated as the
majority of workloads and energy from AWS servers
is used for transfer services.
Assumptions and uncertainties:• The current version (2023) of the AWS Customer Carbon
Footprint tool provides Scope 1 and Scope 2 emissions,but not Scope 3 (which can be estimated as a significant
portion of emissions). As WeTransfer has adopted alocation-based approach, we have assumed that thelocation-based emissions are simply the ‘AWS emissions’+ ‘emissions saved from RE’. Finally, whilst the team
had confidence that AWS were applying a robust
approach to measuring and allocating emissions totheir customers, we were not able to view a detailed
methodology document that outlines their approach.
As such, this data was taken ‘as is’.allocating emissions
to their customers, we were not able to view a detailed
methodology document that outlines their approach.
As such, this data was taken ‘as is’.

41

10 | Appendix• The emissions from AWS also include the energy/
associated emissions with running WeTransfer’s mobile
application. However, this study exclusively addresses
ads on desktop and laptops.
Plans and opportunities for improvement in calculation:• Many of the technical processes required to deliver an ad
are done using workloads on cloud infrastructure - either
controlled by WeTransfer or with strategic partners. An areaof opportunity is to tag AWS cost usage to better isolate
ads-specific infrastructure. This can split out specificusage for serving ads versus other WeTransfer functions,
including file transfer, upload, download and storage.
• AWS has announced that the Scope 3 emissions will
be made available in early 2024. A new assessment will becompleted when a full year of data is available. In addition,
WeTransfer’s platform (server architecture) teams have
set up Cloud Carbon Footprint to use as an additional
dashboard to compare emissions with the AWS dashboard.
Over time, the aggregated data in Cloud Carbon Footprint
will provide us more insights into Scope 1, 2 and 3
emissions for our full server usage and we can makean informed decision on which metrics to use for the
next assessment.
• WeTransfer has already made significant progress inaddressing emissions from the server usage. In 2022,| Make better ads whitepaper 2023

WeTransfer partnered with AWS, and took a hard lookat how much carbon we were emitting. We prioritized
two paths to execute while saving costs and reducing
emissions. For WeTransfer, this meant optimizing how westored files and ensuring that autoscaling was enabled.
WeTransfer is committed to addressing further emissions
and finding ways to optimize our server user, to continue
to reduce the environmental impact of our cloud storage.
Read more about this in WeTransfer’s 2022 Responsible
Business Report.
Ad Management Partner
Date range: January-December 2022
Data source: Primary
Key Metrics:• Partner’s AWS emissions (AWS’s Customer Carbon
Footprint tool)• % of total Ad Decision Requests (ADRs) from WeTransfer
as a proportion of partner’s total ADRs - to attribute AWS
emissions estimate.
• 2021 CO2 footprint (most recent available)
Allocation approach and effect on interpretationof footprint results:• As this partner was able to provide the percentage
of ADRs specifically from WeTransfer, it was possible
to achieve a more accurate estimate of the amountof their server emissions related to serving
an ad on wetransfer.com.
Assumptions and uncertainties:• It is assumed that this partner’s AWS footprint relates
to their entire server operations. WeTransfer has received
verbal confirmation of this. WeTransfer have excluded
emissions from this partner’s employees that work on the
ad server for WeTransfer, as they are a small, office-based
company, and it is suggested that this is de minimis.
Plans and opportunities for improvement in calculation:• Further engage partner to tag their server instances,
so that they are able to provide a specific footprint for
WeTransfer, as the energy intensity of one ADR mayvary between their customers.
• Understand partner’s own footprint (Scope 1 and 2)
in more detail, to understand its significance if thiswas included.
• To reduce emissions down the digital supply chain,
the WeTransfer platform team is sharing learnings
and best practices from work to reduce server costs
and emissions.
• In addition, we have assumed that partner’s
own operation emissions allocated to WeTransfer
is de minimis.

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10 | Appendix

Ad Engineering Partner
Date range: January-December 2022
Data source: Estimated• After engaging with the Ad Engineering Partner, they
were unable to provide us with primary data. WeTransfer
therefore used a spend-based approach to estimate theemissions from this supplier. We used environmentallyextended input-output (EEIO) factors to complete this.
WeTransfer used the US Environmental Protection Agency(EPA) factor for Software. WeTransfer also sense-checked
this against the UK’s Department for Business, Energy &Industrial Strategy (BEIS)*, emissions factor, which was
similar but gave a slightly lower result. Therefore we used
the EPA factor.
Key Metrics:• Emissions based on euro (EUR) spend in 2022
Allocation approach and effect on interpretationof footprint results:• As outlined above, WeTransfer did not receive primarydata from the Ad Engineering Partner, therefore it was
not not needed to allocate based on a usage metric.
WeTransfer used a spend-based metric for allocating
emissions based on industry averages. This is explained
further in the data source and assumptions section.

• Assumptions and uncertainties:• Spend-based methods are typically significantly
lower in certainty, as it is not supplier or geographicallyspecific. However, as these emissions are low,
WeTransfer has accepted this estimate for the purposesof this assessment.
Plans and opportunities for improvement in calculation:• Continue to request specific usage from WeTransfer
services from Ad Engineering Partner to increasetransparency and accuracy in calculation.
• Encourage and work with Ad Engineering Partner togather GHG emissions reports from their data center
providers, and develop a way to attribute to WeTransfer
based on server usage (as per Ad Server partner) or
another activity metric.
Ad Analytics (Traffic)
Date range: January-December 2022
Data source: Primary from WeTransfer teams
Key Metrics:• Active time on page (engagement time)
Assumptions and uncertainties:• The key uncertainty around this Ad Analytics data is how‘time on page’ is measured and whether this is accurate,
especially whether the time on page includes only time

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when the user has the site on page.
• In addition, this provider may not accurately measure,or filter out, non-human users on the site (such as botsand crawlers). However, this issue was mitigated by
the fact that WeTransfer uses Ad Analytics data (which
is linked to ad tracking and billing) to understand thetotal number of sessions, and only used GA to estimate
active time on page.
Plans and opportunities for improvement in calculation:• The Data Analytics team has an upgrade from Universal
Analytics to Google Analytics 4 on the roadmap, whichcalculates additional metrics which is likely to provide
more clarity on time on page.
Ad Analytics (dataset used for User Devices input)
Date range: January-December 2022
Data source: Extracted by WeTransfer AdTech team
Key metrics:• Number of sessions per country (used to calculate
the user time on page)• Number of impressions per country (used to calculate theemissions per impression, and data volume transferred).

*BEIS has been replaced by Department for Energy Security and Net

Zero,Department for Science, Innovation and Technology, and Department
for Business and Trade43

10 | Appendix

Uncertainties:• Overall, WeTransfer is highly confident that the Ad Analytics
data is accurate. This is because this data is used to billclients based on the number of impressions, and the datacollection approach is compliant with advertising industry
standard (IAB).
Emissions Factors
Data source: International Energy Agency (IEA)
Emissions Factors 2022
Date range: 2020 (year that the IEA emissions
data relates to)
Key metrics:• Carbon intensity of electricity generation (CO2e)• To clarify, the DIMPACT team calculated the CO2e figures
by summing the emissions / kWh for CO2, CH4 and NO2
for each country.
The DIMPACT tool provides input of custom emissions
factors for selected countries, and a ‘rest of the world’ input.
Using the IEA data, we calculated a custom figure for thisfield, using a weighted-average figure based on the numberof sessions. This is discussed in more detailin the section above.
For the internet transmission networks, there is a single input
field to convert the electricity consumption of this process
to CO2e emissions. We conducted a similar weighted| Make better ads whitepaper 2023

average calculation based on impressions (as impressions
were commensurable with data volume).
Assumptions and uncertainties:• The IEA data is generally seen as good practicefor reporting, but the ‘temporal lag’ of this data is anuncertainty, as they don’t give clarity on the emissions
intensity of electricity consumption in the reporting year
• However, IEA covered a majority of countries where
WeTransfer has users, therefore gave strong geographicalcoverage.
End-user Device Power Data
Date range: N/A
Data source: DIMPACT analysis
Key Metrics:• The user device profile (what devices users are using
to access WeTransfer) currently are fixed globally,
therefore it does take into account differences between
countries (e.g. it wouldn’t take into account if moreusers use desktops in France than in India). This isbecause there is a lack of data to get this information
at the country level - especially with a global user base.
Plans and opportunities for improvement in calculation:• WeTransfer to explore whether any tools are available
to get a better understanding of what devices are being
used to access content.
• Update the list of countries to the most relevant for
WeTransfers based on users.
Through DIMPACT, conduct a review of default power
consumption data as new information becomes available
on the installed base.

• Typical power consumption of end-user devices(desktops & laptops)• Typical power consumption of CPE• Proportion of laptops to desktops
Assumptions and uncertainties:• The major area of uncertainty is determining the actual
devices and setups that users are using (desktop vs. laptop
with monitor), as internal data from WeTransfer on this was
not available. As such, the DIMPACT defaults were used(see discussion in the DIMPACT methodology on thesedefaults).
44

10 | Appendix

SUMMARY ON CHALLENGES IN COLLECTING
TRANSPARENT DATA FOR INITIAL CALCULATIONThis assessment is the first of its kind for WeTransfer
and still developing in the digital advertising industry.
As such, challenges were encountered when gathering
data - or matching consumption and emissions directly
to WeTransfer’s ads. In these cases, WeTransfer has madesome simplifying assumptions or proxy metrics in orderto reach our initial assessment.
WeTransfer worked with a third party (the Carbon Trust)to review and assess the measurement for transparency
and credibility. In addition, WeTransfer is publishing themethodology to make it clear that this is an initial calculation,
being clear of the assumptions that were made, and layingout a call for feedback and wider industry action to increasetransparency and standardization where possible.
The first need for more transparency is with suppliers
within the ad industry. WeTransfer was very pleased
with the willingness to help from several key suppliers.
However, these providers were not yet set up to provide
detailed emissions data that disaggregated the data
center workloads from their other clients from
WeTransfer’s workload.
WeTransfer and DIMPACT, working with the cloud providers
can play a role in sharing best practice and specifying| Make better ads whitepaper 2023

a roadmap for suppliers to provide this information in astandard way - so that it’s recognised amongst the industry,and becomes a streamlined process that requires minimal
resource from suppliers every time this is requested.
Another challenge and area for improvement is theattribution of end-user device energy. As mentioned above,the end-user device energy is based on active time on page
- not the total number of impressions served (which would
include end-user device energy when the user is doing
something else on their device - this energy is attributed
to another service unrelated to this assessment). Notehere that the data transfer from serving all impressions is
included in the assessment. This means that all impressions
in this assessment have a uniform carbon cost. However,
WeTransfer knows premium ads that are delivered first are
more likely to be on the active screen, thus should arguably
have a higher carbon cost than ads that are more likely
not seen.
A more granular view of which ads are shown during Active
view time would mean that different campaigns could havetheir own unique carbon footprint (not based on a uniform
per impression value). To enable this would require enhanced
measurement of engagement and ad views. WeTransfer isaware of potential commercial sensitivities around the rate
at which impressions are actually viewed, so we recommend
further investigation to explore if this is built into ad pricing
before publicly reporting this information.

45

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Authors and acknowledgements
THANK YOUTo everyone behind this report.
To our partners in measuring and addressing
the footprint of a WeTransfer ad, DIMPACT,The Carbon Trust, and Ad Net Zero.
To the industry leading media agencies
for participating in the focus groups including
Essencemediacom, dentsu, UM, Havas, PHD,
and mSix&Partners.
To all our employees, past and present, whohave made WeTransfer the company it is today.

The document was written by:
Becca Samson, WeTransfer
Davy McGeorge, WeTransfer
Will Pickett, Carnstone
EXTERNAL REVIEW
Matt Anderson, The Carbon TrustPaul Shabajee, University of Bristol| Make better ads whitepaper 2023

Designed by:
Robbie Kerr, WeTransfer creative studioPaul Metsers, WeTransfer creative studio
Poject management:
Eveline Oude Ophuis, WeTransfer creative studio
About WeTransfer and WeTransfer Advertising
WeTransfer streamlines the workflow process for millionsof creative professionals. Its ecosystem of creative
productivity tools makes it easy to collaborate, share anddeliver work. WeTransfer has more than 80 million monthly
active users in 190 countries.
As a certified B Corporation™, WeTransfer has long beena champion of using business as a force for good. Since
its founding in 2009, WeTransfer has donated up to 30%
of its advertising space to support artists and social causes.
Last year, WeTransfer also launched its Supporting Act
Foundation to support emerging creative talent througharts education, grants, and an annual prize.
About DIMPACT
DIMPACT is a collaborative initiative between leading
media, entertainment and technology companies andworld-class researchers. Part tool and part community,
DIMPACT has been developed with cutting-edge expertisefrom computer scientists at the University of Bristol, andis convened and delivered by Carnstone, a sustainability
consultancy based in London.

Created to measure, understand and ultimately reduce
the emissions of serving digital media and entertainment
products, DIMPACT’s web application takes the complexity
out of calculating the carbon emissions of delivering digital
media and entertainment products.
DIMPACT’s community of organizations started at nine
but is now made up of over twenty companies from acrossthe media, entertainment and technology sectors, all withan interest in working to reduce their digital emissions
and bring transparency to consumers, business, and thesustainability community.
About The Carbon Trust
The Carbon Trust is a global climate consultancy driven
by the mission to accelerate the move to a decarbonised
future. Climate pioneers for over 20 years, it partners withbusinesses, governments and financial institutions to drive
positive climate action.
From strategic planning and target setting to
implementation and communication, The Carbon Trustturns ambition into impact. To date, its 400 experts havehelped set over 200 science-based targets and guided
more than 3,000 organizations and cities across fivecontinents on their route to Net Zero.

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10 | Appendix

Core Definitions
Advertising Management
Processes involved in selling and managing advertisinginventory, managed by Ad Ops team and carried out by
Ad Server.
Ad Analytics
Processes used to provide feedback, dashboard andanalysis of advertising performance, including impressions.
Ad Config
This includes ad position information, ad platform (desktop,
mobile web, mobile app) the location and file paths to the Ad
Creative and campaign metadata such as target countries.
Ad Server Services
This includes all of the infrastructure to render, track, monitor
and display our ads.
Ad Production
This references the WeTransfer Studio department thatcreates the ads. This includes designers creating assets,engineers creating html/js/css or copywriters producing
content.
Ad Proxy (K8s)“K8s” is a shortened term for “Kubernetes” [K + 8 letters + s].
We run our Ad Proxy in a K8s cluster which is part of our main

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AWS infrastructure. This is the real time production
backend system which communicates with the Ad
Management system and delivers the data for the
AdSDK to render the ad.
Active View
The amount of time that the page is within view by thecustomer. This means, if a user switches window or tabon the browser, the active time would be paused to give
WeTransfer an understanding of how long users are actuallyviewing an ad (as measured by Google Analytics).
Content Delivery Network (CDN)
A network of interconnected servers that speeds up
webpage loading for data-heavy applications. This iscarried out by AWS and referred to as AdSDK (S3 CDN).
CDN Origin and Caching Services
Processes that provide origin content for a CDN service
or caching service for WeTransfer servers. This is carriedout by AWS.
Climate neutral certified organization
WeTransfer has removed as much carbon dioxide fromthe atmosphere as they put into it. Each year they present
progress to a certified third party auditor that they are
working to reduce and eliminate the greenhouse gas
emissions from running the business as much as possible,and compensate for all of the unavoidable emissions throughcertified carbon offset schemes.

Cradle to Gate Model
A partial life cycle analysis model that assesses
a product’s environmental footprint from raw materials
extraction (cradle) until it leaves the factory-“gate”.
(i.e. before transported to the consumer).
Cradle to Grave Model
Full life cycle analysis from resource extraction (‘cradle’),production, use phase and disposal phase (‘grave’).
Content License Management
Processes involved in managing content licensing
for the service.
Content (and Metadata) Management Services
Content management systems and content processing
involved in management of content and any specificmetadata management about that content (illustrated
in the system diagram).
Content Processing
Processes involved in receiving and processing content
for ingestion to the service.
Content Storage (Ad Creative)
Media and content storage independent of Content
Management (e.g. video, images, pdf documents, etc.).
This is carried out by AWS (S3).

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Content Upload
This includes all processes involved in bringing content anddata into the service and any editing prior to or as part-ofingestion processes. This is executed through AWS (S3).
Embodied Emissions
All greenhouse gas emissions that are released as partof making a product or service ready for your consumption
or use. In the case of a digital ad, an example is theemissions generated from building a functional server
including extraction of metal, transportation to factoryand construction of server building.
Engineering Analytics
Used for real time error reporting, performance andmonitoring. It is part of our observability stack and alerts
the engineering team to critical availability issues.
This is carried out by the Ad Engineering Partner.
Life Cycle Analysis (LCA)
The systematic analysis of the potential environmental
impacts of products or services during their entire life
cycle. The complete process of LCA includes goal andscope definition, inventory analysis, impact assessment,
and interpretation.
Load Balancing
These services enable adaptation to variations in demand.
This is carried out by AWS (Cloudfront) and the Content
Display Network (CDN).

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Page View
An instance of a user visiting a page on WeTransfer.com.
This is slightly difficult to define as WeTransfer is a single
page service. For example, if a unique URL changes, suchas /corporate or /corporate/about/ that is classed as two
different pages. There are some nuances when we haveadvertising features such as sliding panels and overlays.
Product Analytics (User Analytics)
The process of analyzing how users engage with an ad.
The process of providing metrics to show how many users
engaged on WeTransfer and behavioral data, such as
time on site.
Product Carbon Footprint (PCF)
A measurement of the total greenhouse gas
emissions generated by a product, from extractionof raw materials, to end-of-life. It is measured incarbon dioxide equivalents (CO2e).

SessionA browser session from start to finish. For example,
a user who visits wetransfer.com and starts clickingaround. A session will span actions across multiple pages
on the site (as measured by Google Analytics).
Transfer Client (App)This is the section of the site that handles the actual
transferring of files. For an ad to render and an impression
to count the Transfer App needs to initialize and load
its components into the page.
Web Hosting
Used to host and serve web pages and content
for assessed service(s). In this case WeTransfer
ads. This is carried out by AWS (S3).

Product Category Rule (PCR)
Category-specific guidance for estimating and reporting
product life cycle environmental impacts, typically in theform of environmental product declarations and productcarbon footprints.

Viewable Impression
A viewable impression is a standard measure of ad
viewability defined by the International Advertising Bureau(IAB) to be an ad, which appears at least 50% on screen
for more than one second. The standards used by
WeTransfer are the IAB standards for viewability, which
are verified using measurement service, and this datais also collected via Ad Analytics tool.

Scope 3 Emissions
All other indirect emissions that occur in the upstream
and downstream activities of an organization.

Other definitions can be found in our most recent
responsible business report (Jargon Buster): https://wetransfer.com/blog/story/making-a-difference-together/48

Inquiries
For more information about the content
of this document please contact:
Lina Ruiz, Director of Social Responsibility
responsibility@wetransfer.com