TRANSFORMING GLOBAL

DIABETES CAREInvestor Presentation | July 2020

2

Safe Harbor Statement

This presentation contains “forward” looking statements that are based on our management’s beliefs and assumptions and on information currently available to

management. We intend for such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in the U.S.

Private Securities Litigation Reform Act of 1995. Forward-looking statements include information concerning our possible or assumed strategy, future operations,

financing plans, operating model, financial position, future revenues, projected costs, competitive position, industry environment, potential growth opportunities,

potential market opportunities, plans and objectives of management and the effects of competition on our business. These also include statements with respect to

the impacts of the COVID-19 pandemic on Dexcom and the timing of updated 2020 annual guidance

Forward-looking statements include all statements that are not historical facts and can be identified by terms such as “anticipates,” “believes,” “could,” “seeks,”

“estimates,” “targets,” “guidance,” “expects,” “intends,” “may,” “plans,” “potential,” “predicts,” “prospects,” “projects,” “should,” “will,” “would” or similar expressions

and the negatives of those terms, although not all forward-looking statements contain these identifying words.

Forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to

be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. We cannot guarantee that

we will achieve the plans, intentions, or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking

statements.

The risks and uncertainties that may cause actual results to differ materially from DexCom’s current expectations are more fully described in DexCom’s annual

report on Form 10-K for the period ended December 31, 2019, as filed with the Securities and Exchange Commission on February 13, 2020, its most recent

quarterly report on Form 10-Q for the period ended June 30, 2020, as filed with the Securities and Exchange Commission on July 28, 2020, and its other reports,

each as filed with the Securities and Exchange Commission. DexCom assumes no obligation to update any such forward-looking statement after the date of this

report or to conform these forward-looking statements to actual results.

The accompanying presentation dated July 28, 2020 contains non-GAAP financial measures. The appendix reconciles the non-GAAP financial measures in that

presentation to the most directly comparable financial measures prepared in accordance with Generally Accepted Accounting Principles (GAAP). These non-

GAAP financial measures include non-GAAP gross profit margin, non-GAAP operating income (loss), non-GAAP net income (loss), and non-GAAP net income

(loss) per share as well as adjusted EBITDA.

DexCom reports non-GAAP financial measures in addition to, and not as a substitute for, or superior to, measures of financial performance prepared in

accordance with GAAP. These non-GAAP financial measures are not based on any comprehensive set of accounting rules or principles, differ from GAAP

measures with the same names, and may differ from non-GAAP financial measures with the same or similar names that are used by other companies. We believe

that non-GAAP financial measures should only be used to evaluate our results of operations in conjunction with the corresponding GAAP financial

measures. We encourage investors to carefully consider our results under GAAP, as well as our supplemental non-GAAP information and the reconciliations

between these presentations, to more fully understand our business.

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Second Quarter 2020

Resilient growth with

$452 million in revenue

Operational

Highlights

35% constant currency

revenue growth (38% US;

22% OUS)

Key Financial

Highlights

Successfully doubled G6

capacity during the first

half of 2020

Solidified balance sheet with

$1.2 billion convertible note

offering in May

Year-over-year Operating

Margin expansion of more

than 1500 basis points

Commenced launch of

G6 Pro*

*Launched on a limited basis in Q2 with the expanded launch occurring in early July.

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2020 Guidance as of July 28, 2020

2020 Annual Revenue and Profitability Guidance

Revenue Non-GAAP

Gross Margin*

Non-GAAP

Operating Margin*Adjusted EBITDA

Margin*

Key Considerations

• Strong patient

volume growth with

some ongoing

COVID impact

• Pharmacy channel

and customer

access initiatives

• Some deferred

opex into 2H20 as

a result of COVID

(G7 trials, DTC

marketing)

~$1.850

billionMeet or

Exceed 65%

Meet or

Exceed 14%

Meet or

Exceed 24%

*See appendix for reconciliations to GAAP metrics. Adjusted EBITDA defined as EBITDA adjusted to exclude non-recurring charges and stock-based compensation.

CGM AND DIABETES MANAGEMENT

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A Global Crisis that Remains Uncontrolled

*Actual rates of diagnosis, treatment, targets, and outcomes vary in different countries. ** That is, recommended glucose levels. We believe the outcomes have not varied significantly since

this framework was expounded by Hart JT, “Rule of halves: Implications of increasing diagnosis and reducing dropout for future workload and prescribing costs in primary care,” Brit J Gen

Pract. 1992, 42:116-119.

Note: 463 million estimate for adults with Diabetes based on the 2019 IDF Atlas.

Break the

EpidemicOnly around 6% of people with diabetes live a life free from diabetes-related complications.*

Diabetes 100%of the estimated 463 million

adults with diabetes

50% Diagnosed*

25% Receive

Care 12.5% Achieve

targets**

6% Achieve

desired outcomesLive a life free from diabetes-

related complications

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CGM at the Center of Diabetes Management

Analytics

• Algorithms

• Outcome Measurement

• Decision Support &

Coaching

Service

• Clinicians

• Hospitals

• Education

Drugs

• Insulins

• Other T2 Compounds

• Other Medications

Drug Delivery

• Pens

• Disposable Pumps

• Durable Pumps & Supplies

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Dexcom U.S. Market Opportunity – Core IIT Market

Total U.S. Market Size – People on Intensive Insulin Therapy

Core Intensive Business

Million People

~3.3

We remain in the early stages of the transition from fingersticks to CGM as standard of care

Estimated CGM Market

Penetration1

U.S. Type 1: ~40%

U.S. Type 2 Intensive: ~15-20%

Note: IIT = Intensive insulin therapy, those whose insulin regimen includes mealtime insulin.1) Based on internal estimates and third-party data providers as of 03/31/20. Includes users of flash glucose monitors (FGM or intermittently scanned CGM).

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OUS Remains a Significant Growth Opportunity for IIT

◼ Core market ◼ Limited existing presence ◼ New market opportunity

Dexcom’s core IIT market consists of 7-8 million people, with OUS penetration significantly less than the U.S.

Leverage additional scale to continue

OUS G6 rollout and extend geographic

presence (e.g. Japan, South Korea)

New geographies1 represent a >5x TAM

expansion opportunity relative to

existing core markets

Key 2020 Initiatives

Continue market access efforts in core

markets

Note: IIT = Intensive insulin therapy, those whose insulin regimen includes mealtime insulin.1) Based on Wall Street research estimates for people on intensive insulin therapy. This includes India, in which Dexcom’s existing presence is minimal.

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Diabetes Management Is a Constant Balancing Act

0

20

40

60

80

100

120

140

160

180

200

220

240

260

280

300

320

340

Glu

co

se

(m

g/d

l)

120

100

80

140

Cardiovascular disease

Blindness

Kidney failure

Nerve degeneration

Diminished cognitive function

Loss of consciousness

Potential death

Target Glucose Range

350

1) Murata GH, Hoffman RM, Shah JH, Wendel CS, Duckworth WC: A probabilistic model for predicting hypoglycemia in type 2 diabetes mellitus: the Diabetes Outcomes in Veterans Study (DOVES). ArchIntern Med 2004;164:1445–1450

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Intermittent Monitoring is Not Enough

0

20

40

60

80

100

120

140

160

180

200

220

240

260

280

300

320

340

Glu

co

se

(m

g/d

l)

Time (hours)

0 242 4 6 8 10 12 14 16 18 20 22

Target Glucose Range

120

SMBG*

120

100

80

140

350

*As compared to Self Monitoring of Blood Glucose (SMBG)

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Intermittent Monitoring Is Not Enough

0

20

40

60

80

100

120

140

160

180

200

220

240

260

280

300

320

340

Glu

co

se

(m

g/d

l)

Time (hours)

0 242 4 6 8 10 12 14 16 18 20 22

CGM

DANGEROUS LOW FOR 1 HOUR

OVER 4 HOURS ABOVE 210 BEFORE SMBG*

ABOVE 140 FOR 13.5 HOURS

120

100

80

140

350

*Self Monitoring of Blood Glucose (SMBG)

Target Glucose Range

13

Intermittent Monitoring Is Not Enough

0

20

40

60

80

100

120

140

160

180

200

220

240

260

280

300

320

340

Glu

co

se

(m

g/d

l)

Time (hours)

0 242 4 6 8 10 12 14 16 18 20 22

CGM

DANGEROUS LOW FOR 1 HOUR

OVER 4 HOURS ABOVE 210 BEFORE SMBG

ABOVE 140 FOR 13.5 HOURS

120

100

80

140

350

*Self Monitoring of Blood Glucose (SMBG)

Healthy Glucose Range

Only real-time CGM can alert a patient to take necessary action

THIS IS WHERE IT

STARTS

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Proven Outcomes with Dexcom CGM

1 Compare this outcome relative to the recent 3-year Time in Range results for intermittently-scanned CGM in the following two studies: Soupal J, Petruzelkova L, Grunberger G, et al. “Glycemic Outcomes in Adults With T1D Are

Impacted More by Continuous Glucose Monitoring Than by Insulin Delivery Method: 3 Years of Follow-Up From the COMISAIR Study.” Diabetes Care. 2019; and Charleer S, et al. “Quality of Life and Glucose Control After 1

Year of Nationwide Reimbursement of Intermittently Scanned Continuous Glucose Monitoring in Adults Living with Type 1 Diabetes (Future): A Prospective Observational Real-World Cohort Study,” Diabetes Care. 2019.2 The DIaMonD Study, JAMA Jan 2017. The GOLD study, Lind M, et al JAMA. 2017;317(4):363-364. 3Šoupal J, Petruželková L, Flekač M et al. Comparison of Different Treatment Modalities for Type 1 Diabetes, Including

Sensor-Augmented Insulin Regimens, in 52 Weeks of Follow-Up: A COMISAIR Study. Diabetes Technology & Therapeutics. 2016;18(9):532-538 4Ehrhardt NM, Chellappa M. J Diabetes Sci Technol. 2011;5(3):668-675. 5Anderson J, Attvall S, Sternemalm L, et al. J Diabetes Sci Technol. 2011;5(6):1472-9. Observational study. 6Bailey TS, Zisser HC, Garg SK: Diabetes Technol Ther. 2007;9:203–210. a1.2 point reduction in A1C observed when CGM was worn at least 85% of the time.b1.4 point reduction in A1C from observational study where 77.9% of study population had T1D and baseline HbA1c > 9.0%.

Dexcom continuous glucose monitoring (CGM) enables

Time in Range improvement of greater than 20%1

Outcomes achieved regardless of method of insulin delivery (pump vs. pen)

Dexcom CGM significantly lowers HbA1C for those with type 2 and

type 1 diabetes4-6

Reductions average 1.2 and 1.4 percentage pointsa,b from baseline.

T1T2

Continuous glucose monitoring (CGM)–not the insulin delivery

method–drives A1C reduction2-3

Patients on MDI + CGM saw greater improvement than those on Pump

Therapy + SMBG

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iCGM: Interoperability in Insulin DeliveryDexcom positioned to drive multiple commercial offerings in 2020

Insulin Pumps

Smart Insulin Pens

Insulin Patch Pumps

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Strategic OutlookDexcom CGM is a Platform Technology

Dexcom

CGM

IntensiveCore Dexcom

Population Health• T2D (Non-intensive)

• Pre-Diabetes

• Disease

Management

Healthcare

Facilities• Hospitals

• Skilled Nursing

Facilities

• Post-Acute Care

Pregnancy• People with Diabetes

who are Pregnant

• Gestational

Successfully doubled G6 capacity,

well-positioned to support future

growth opportunities.

Proceeding with G7 manufacturing

scale-up and in-clinic work.

Updates on Key 2020 Initiatives

1

2

3

Dexcom value proposition validated in

new markets during the pandemic, with

examples of expanded use of CGM in

population health, healthcare facilities,

and pregnancy.1

1Examples include the interim CMS ruling not to enforce certain clinical criteria during the pandemic (https://www.cms.gov/newsroom/press-releases/trump-administration-issues-

second-round-sweeping-changes-support-us-healthcare-system-during-covid); the FDA’s temporary allowance for use of Dexcom CGM in the inpatient setting

(https://www.dexcom.com/hospitalcovid-19); and Health Canada’s July announcement authorizing the interim use of Dexcom’s G6 for women who are pregnant with diabetes

(https://investors.dexcom.com/news-releases/news-release-details/health-canada-authorizes-interim-use-dexcom-g6-cgm-pregnant).

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Expanding Our Market Opportunity: Type 2 Non-Intensive

Total U.S. Market Size1 and Clinical Validation of CGM

1. Total U.S. PWD (https://www.cdc.gov/media/releases/2017/p0718-diabetes-report.html) less IIT population.

2. The International Consensus on Time in Range consisted of a panel of global experts that convened at ATTD in 2019. Results were published following the 2019 ADA conference. See Battelino

et al. “Clinical Targets for Continuous Glucose Monitoring Data Interpretation: Recommendations from the International Consensus on Time in Range.” Diabetes Care. June 2019.

Rising clinical awareness of the potential for CGM to address the massive problem of Type 2 diabetes

~27 million

The 2019 International Consensus

on Time In Range2 established CGM-

based glycemic targets both Type 1

and Type 2 diabetes

The consensus provides recognition

of CGM value relative to A1c

(existing standard of care for Type 2

diabetes)

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The participants below both have an A1c of 7.1%, but very different glycemic health

CGM Provides Insight Beyond the Existing Standard Metric (A1c) for Type 2 Diabetes

Ave

rag

e G

luco

se

(m

g/d

L)

A1C

87%

13%>180

mg/dL

70- 180 mg/dL

<70 mg/dL

Time in Range

0%

13%

87%

>180 mg/dL

70- 180 mg/dL

<70 mg/dL

Time in Range

0%

Avg Glucose: 224 mg/dL

A1C: 7.1%

Avg Glucose: 136 mg/dL

A1C: 7.1%

*Data drawn from a Dexcom pilot.

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Traditional Care vs. Personalized Care with CGM

100 NPS score

93% of participants said Dexcom G6 was comfortable

to wear

Dexcom Internal Pilot (n=207)

0 participants withdrew from the study

87% changed their food choices based on real-time

CGM data

90% reported that real-time CGM use contributed to

a healthier lifestyle

Real-time CGM and Behavior Modification1

TRADITIONAL TREATMENT PERSONALIZED TREATMENT

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Dexcom CGM as a Driver of User Engagement

1Ehrhardt N. and Al Zaghal E., “Continuous Glucose Monitoring As a Behavior Modification Tool,” Diabetes Care 38 (2020). Published online January 9, 2020.

100 NPS score

93% of participants said Dexcom G6 was comfortable

to wear

Dexcom Internal Pilot (n=207)

0 participants withdrew from the study

87% changed their food choices based on real-time

CGM data

90% reported that real-time CGM use contributed to

a healthier lifestyle

Real-time CGM and Behavior Modification1

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Dexcom CGM as a Driver of Improved Outcomes and EconomicsPreliminary real-world evidence supports potential of Dexcom CGM to improve diabetes cost trends

10-Year Cost Trends Real-World Evidence

1. Total U.S. PWD (https://www.cdc.gov/media/releases/2017/p0718-diabetes-report.html) less IIT population.

2. Self-monitored blood glucose.

3. Cost savings are prior to the cost of the CGM device.

99 matched people, primarily with non-intensive

Type 2 diabetes

49 standard of care SMBG2 vs. 50 G6 CGM for 6

months

Dexcom CGM Cohort Gross Savings:

~$5,000 annualized per member3

2012: $13,735

2007: $11,729

2017: $16,778

U.S. Annual Healthcare Costs per Person

with Diabetes1

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From Clinical Outcomes to Commercial Presence Expanding the use of Dexcom CGM in Type 2 NIIT via multiple partnerships

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The Future of CGM Technology: G7

Real-Time CGM

Factory Calibrated

Extended Sensor Wear

Fully Disposable

Simple Application

Significant Manufacturing Cost

Reduction

CGM to empower

all people