TANDEM DIABETES CARE INC (TNDM) Business

Item 1.    Business

References within this Annual Report to “Tandem,” “we,” “our,” “us,” “management,” or the “Company” refer to Tandem Diabetes Care, Inc., together with its wholly-owned subsidiaries.

Overview

Tandem Diabetes Care is a global leader in insulin delivery and diabetes technology, specializing in the design, development, and commercialization of advanced solutions that reduce the burden of diabetes management. We serve nearly 500,000 people living with diabetes in more than 25 countries worldwide. Our strategy is to offer flexibility and choice in intelligent insulin delivery systems through an accessible portfolio of market-leading pumps, applications and insights. In support of this strategy, our Tandem pump platforms include t:slim X2 and Tandem Mobi (Mobi), both of which feature Control-IQ+ advanced hybrid closed-loop technology.

Diabetes and the Insulin Therapy Management Market

Diabetes is a chronic, life-threatening disease for which there is no known cure. It is typically classified as either type 1 or type 2:

•Type 1 diabetes is characterized by the body’s nearly complete inability to produce insulin. It is frequently diagnosed as an acute event during childhood or adolescence. Individuals with type 1 diabetes require intensive insulin therapy to survive.

•Type 2 diabetes is characterized by the body’s inability to either properly use insulin or produce enough insulin. It’s a progressive condition, and a person in the advanced stages of living with type 2 diabetes often requires intensive insulin therapy. The Center for Disease Control and Prevention estimates Type 2 accounts for 90-95% of diagnosed diabetes in adults in the United States.

We consider our addressable market to be people living with type 1 diabetes and in 2025, we began expanding our addressable market to include people living with type 2 diabetes who require intensive insulin therapy. Throughout this Annual Report, we refer to these individuals as people with insulin-dependent diabetes. In the geographies we serve, we estimate about 5 million people live with type 1 diabetes of whom approximately 2 million reside in the United States. We estimate about 2.5 million people in the United States live with type 2 diabetes and require intensive insulin therapy.

Diabetes can be challenging to manage. Unlike most therapies, insulin requirements can vary greatly and can be affected by many factors, such as type or quantity of food eaten, illness, stress and exercise. Preventing and managing fluctuations in blood glucose levels between hypoglycemia, or low blood glucose levels, and hyperglycemia, or high blood glucose levels, is often time consuming and stressful.

There are two primary therapies used by people with insulin-dependent diabetes, Multiple Daily Injection (MDI) and insulin pumps. Insulin pumps are intended to more closely resemble the physiologic function of a healthy pancreas and use rapid-acting insulin to fulfill both mealtime (bolus) and background (basal) requirements. Insulin pump systems are typically considered either durable or disposable. Durable systems are comprised of a programmable device, which is designed to last for multiple years, and which connect to single-use supplies that provide an insulin reservoir and cannula to administer insulin into the body that are expected to be replaced every three to seven days. By comparison, disposable systems combine the programmable device, which includes battery and electronics, with the insulin reservoir and cannula and are entirely disposed of by the user every three days. In both systems, the insulin reservoir is typically filled by the user.

Insulin pumps often feature automated insulin delivery (AID) algorithms, which use continuous glucose monitoring (CGM) sensor information to automatically adjust insulin dosing, and are designed to improve blood glucose control and increase a user’s time in their targeted glycemic range, while reducing the burden of diabetes management. The American Diabetes Association Standards of Care state that diabetes devices should be offered to people with diabetes. It also states that AID systems are preferred over non-automated pumps and MDI, and should be offered for diabetes management to youth and adults with type 1 diabetes. The worldwide insulin pump market remains highly underpenetrated. In the United States, approximately 40% of individuals with Type 1 diabetes, and 5% of individuals with Type 2 diabetes, use insulin pump therapy. Internationally, average insulin pump adoption is estimated to be approximately 20%.

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Our Technology: Improving the Lives of People with Insulin-Dependent Diabetes

Our AID Systems

We develop our automated insulin delivery systems and related technology solutions using a consumer-focused approach. We initially rely on the use of behavioral sciences, including extensive research to ascertain what people with insulin-dependent diabetes require and prefer from their diabetes therapy. We then look to modern consumer technology for inspiration and design our hardware and software solutions to try to meet the specific demands of people living with diabetes. This multi-step approach has resulted in a differentiated device portfolio that provide users with the distinct features and functionality they seek and in a manner that makes the features usable and intuitive.

We offer durable insulin pumps that are designed for years of daily use. We sell single-use supplies that are used together with our pumps and are replaced every few days. These supplies include cartridges for storing insulin, and infusion sets that contain a cannula and connect the pump to a user’s body to administer insulin. We launched our flagship t:slim pump platform in August 2012, and its next generation, the t:slim X2, in October 2016. In 2024, we expanded our portfolio with the commercial availability of Mobi with iOS control in the United States. In December 2025, we further expanded the availability of Mobi to Android users in the U.S. Our insulin pumps are fully detachable, offer Bluetooth connectivity and are typically used as part of an AID system.

When used as an AID system, our insulin pumps are integrated with a CGM and powered by our Control-IQ+ technology. Results from four independent pivotal studies using Control-IQ technology have been published in the New England Journal of Medicine since 2019. Control-IQ+ launched in 2025 and is our third and newest AID algorithm, which is available globally and indicated for people as young as ages 2+ (type 1). It is also indicated for people 18+ (type 2) in the United States. This hybrid closed loop algorithm increases a user's time in targeted glycemic range (70-180 mg/dL) by predicting and helping to prevent the frequency and/or duration of hyperglycemic and/or hypoglycemic events. It is the only predictive algorithm featuring AutoBolus, corrective bolusing. Control-IQ+ also offers an easy set-up feature and settings for sleep and exercise activities that adjust the algorithm parameters to better match the different physiological needs during these activities.

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Our AID systems offer users the choice of integrating with multiple CGM sensors. In 2025, our pumps integrated with sensors such as the Dexcom G6 and G7, and the Abbott FreeStyle Libre 2 Plus. In December 2025, we launched t:slim X2 integration with Abbott FreeStyle Libre 3 Plus in the U.S. Mobi was available with Dexcom G6 and G7 integration in the U.S., and we plan to expand its integration offerings to include Abbott FreeStyle Libre 3 Plus. Our extensive experience in CGM integration over the past decade represents our commitment to provide customizable solutions to help reduce burden and create new possibilities for people living with diabetes.

Tandem Device Updater

This tool allows Tandem pump users to update their pump software quickly and easily from a personal computer. It is PC and Mac compatible and designed to work with our pumps in a manner similar to software updates on a smartphone. We have used this technology worldwide to offer software updates to our in-warranty customers at no cost.

Tandem Source

Our web-based data management platform provides users, their caregivers and their healthcare providers with a fast, easy and visual way to display diabetes therapy management data from our pumps and integrated CGMs. Tandem Source also provides us with data that we can analyze to reveal patterns, trends, outcomes and associations that can be used to improve our products and in the analysis of clinical outcomes data. Tandem Source is available in the majority of markets we serve globally and was designed to bring together the features of Tandem’s legacy t:connect, t:connect HCP, and t:connect Portal offerings with new comprehensive data reporting in one central, scalable platform. It offers automatic data transfers from pumps using a mobile app to keep online data current and remove the need for manual pump uploads.

Sugarmate

Sugarmate is a mobile app that is designed to help people visualize diabetes therapy data in innovative ways. It allows users to log glucose data and health and nutrition information, and can provide notifications and alerts to users, their family, and their caregivers.

Our Strategy & Future Technologies

Diabetes management can vary greatly from person-to-person, creating multiple market segments based on clinical needs, personal preferences and affordability. Our strategy is to redefine global leadership in insulin delivery solutions through commercial excellence, patient-first reimbursement choices, and a differentiated device portfolio. We strive to offer all people with insulin-dependent diabetes flexibility and choice in their intelligent insulin delivery systems, through our portfolio of market-leading pumps, applications, and insights that improve outcomes and reduce the daily burden of living with diabetes.

In support of this strategy, we continue to drive innovation in our Tandem pump platforms. This includes a novel, extended-wear infusion site option for Mobi that will transform the pump into a tubeless patch device. In addition, our pipeline also includes a next-generation Mobi patch pump that leverages the technology acquired with the Sigi Patch Pump to deliver further miniaturization. Our development efforts also include extended-wear infusion set technology, dual glucose-ketone sensor integration, and algorithm advancement in pursuit of offering fully closed loop technology.

Markets and Distribution Methods

Our technology solutions are now available in more than 25 countries. In the United States and Canada, we have always employed direct sales, customer support, and clinical teams, partnering with independent distributors for order fulfillment. Internationally, we have historically contracted with distributors who have substantial responsibility for sales, customer support, clinical efforts and order fulfillment. We began direct sales, training and customer support activities in 2026, starting with the United Kingdom, Austria, and Switzerland, and intend to continue this transition in additional markets across 2026.

Sales Concentrations and Significant Customers. A small number of independent distributors in the United States and Canada are responsible for order fulfillment. We believe these distributors carry minimal inventory at any given time. In other markets, there may be variability in inventory levels among our distributors, particularly when we begin the transition to our own direct operations or in periods surrounding the launch of new products. For the year ended December 31, 2025, two independent distributors each accounted for more than 10% of our worldwide sales.

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Third-Party Reimbursement

In the United States, we are pursuing a multi-channel coverage and reimbursement strategy, enhancing coverage and reimbursement through both the durable medical equipment (DME) and pharmacy channels. We believe this strategy will improve access and optimize the potential for better medical outcomes for people living with diabetes, while reducing the overall economic burden of diabetes care. This also provides our customers with flexibility in how they use their insurance benefits to simplify onboarding and provide them with the most advantageous reimbursement terms. Our increasing use of the pharmacy channel is discussed in this Annual Report under Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Internationally, insurance reimbursement processes vary by geography. In markets where we have direct operations, we are responsible for all reimbursement, tender application and fulfillment activities. Otherwise, that responsibility lies with our distributors.

Manufacturing and Quality Assurance

Our insulin pumps are currently assembled, tested, and packaged at our facilities in San Diego, California. Our t:slim X2 cartridges are manufactured by an experienced third-party contract manufacturer and packaged at our facilities in San Diego. Our Mobi cartridges have primarily been manufactured at our facilities in San Diego since launch, but we are in the process of transferring those operations to the same contract manufacturer who makes our t:slim X2 cartridges.

Outside suppliers are the source for raw materials, select components and some sub-assemblies used in the production of our insulin pumps and cartridges. We purchase some supplies from a single or limited number of sources because of their proprietary know-how, quality assurance, cost-effectiveness, or constraints due to regulatory requirements. For example, we purchase all of our currently marketed infusion sets from a third-party supplier, Unomedical A/S, a subsidiary of the ConvaTec Group. Unomedical is responsible for all manufacturing, testing, sterilization and packaging of the infusion sets under our brands. Any sole and single source supplier is managed through our supplier management program that is focused on reducing supply chain risk. Certain suppliers are evaluated, approved and monitored periodically by our quality department to ensure conformity with the specifications, policies and procedures applicable to our devices. Members of our quality department also inspect a sample of devices at various steps during the manufacturing cycle to facilitate compliance with our devices’ stringent specifications.

As a medical device manufacturer, our manufacturing facility and the facilities of our sterilization and other critical suppliers are subject to periodic inspection by the FDA, certain corresponding state agencies, and Notified Bodies and foreign regulatory authorities. We have received certification from BSI Group, a Notified Body to the International Standards Organization (ISO), of our quality system. A Notified Body is an entity that has been designated and accredited by the national competent authority of an EU Member State in accordance with applicable EU legislation to perform third-party conformity assessment activities including calibration, testing, certification and inspection of a medical device. Certain processes used in the manufacturing and testing of our devices have been verified and validated as required by the FDA and other regulatory bodies.

We also work closely with our suppliers to ensure continuity of supply while maintaining high quality and reliability. However, due to required medical device manufacturing qualification requirements, we may not be able to quickly establish additional or replacement sources. In the case of sole sourced parts, we manage risk through holding inventory in house and at the supplier to ensure continuity of supply and lower risk of disruption. We purchase many of our components and sub-assemblies from manufacturers with whom we are at least dual sourced and across various geographies.

Intellectual Property

We have made protection of our intellectual property a strategic priority. We rely on a combination of copyright, patent, trademark, trade secret and other intellectual property laws, non-disclosure agreements and other measures to protect our proprietary rights.

As of December 31, 2025, our patent portfolio included numerous issued patents and pending patent applications in the United States and other countries, which in the aggregate, we believe to be important to our business. Patents are generally effective for 20 years from the date the earliest application was filed in the patent family, and in some cases may be extended. Our issued patents as of December 31, 2025 are set to expire over a range of years, from 2026 to 2044, subject to any extensions. We also have various registered United States trademarks, registered European Community trademarks, and other trademark registrations and pending trademark applications in other countries and regions of the world. In addition, we have entered into exclusive and non-exclusive licenses in the ordinary course of business relating to a wide array of technologies or other intellectual property rights or assets.

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Our patents and patent applications seek to protect aspects of key features of our pumps, cartridges, algorithms, infusion sets and pump systems. We believe that our patent position provides us with sufficient rights to protect our current and proposed commercial products. However, our patent applications may not result in issued patents, and any patents that have been issued or might be issued may not protect our intellectual property rights. Furthermore, we operate in an industry characterized by extensive patent litigation, and our patents may not be upheld if challenged. Any patents issued to us may be challenged by third parties as being invalid or unenforceable, and patent litigation may result in significant damage awards and injunctions that could prevent the manufacture and sale of affected products or result in significant royalty payments to continue selling the products. Third parties may also independently develop similar or competing technology that avoids our patents. The steps we have taken may not prevent the misappropriation of our intellectual property, particularly in foreign countries where the laws may not protect our proprietary rights as fully as in the United States. We also face risks associated with intellectual property infringement.

We also rely on trade secrets, technical know-how and continuing innovation to develop and maintain our competitive position. We seek to protect our proprietary information and other intellectual property by generally requiring our employees, consultants, contractors, suppliers, outside scientific collaborators and other advisors to execute non-disclosure and assignment of invention agreements at the start of their employment or engagement. Agreements with our employees also forbid them from bringing the proprietary rights of third parties to us. We also generally require confidentiality or material transfer agreements from third parties that receive our confidential data or materials. We cannot guarantee that employees and third parties will abide by the confidentiality or assignment terms of these agreements. Despite measures taken to protect our intellectual property, unauthorized parties might copy aspects of our products or obtain and use information that we regard as proprietary.

Competition

The medical device industry is intensely competitive, subject to rapid change and highly sensitive to the introduction of new products, treatment techniques or technologies, or other market activities of industry participants. We compete in markets worldwide with companies that manufacture insulin delivery devices, primarily Beta Bionics, Insulet, Medtronic, mylife (formerly Ypsomed) and Sequel. There are also a number of other companies developing and marketing their own insulin delivery systems and/or related software applications for launch in the markets where we operate. In addition, we face competition from a number of companies, medical researchers and existing pharmaceutical companies that are pursuing new delivery devices, sensing technologies, procedures, drugs and other therapeutics for the monitoring, treatment and prevention of diabetes.

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Government Regulation

The medical devices that we manufacture are subject to regulation by numerous regulatory bodies, including the FDA and comparable international regulatory agencies. These agencies require manufacturers of medical devices to comply with applicable laws and regulations governing the development, testing, manufacturing, labeling, marketing and distribution of medical devices. Devices are generally subject to varying levels of regulatory control, the most comprehensive of which requires that a clinical evaluation program be conducted before a device receives approval for commercial distribution. In addition, healthcare regulatory bodies in the United States and around the world impose a range of requirements related to the payment for medical devices and the procedures in which they are used, including laws intended to prevent fraud, waste, and abuse of healthcare dollars.

Regulation of Medical Devices in the United States

Our products are medical devices subject to extensive and ongoing regulation by the FDA and other federal and state regulatory authorities. The FDA’s regulations govern product design and development, pre-clinical and clinical testing, pre-market clearance, authorization or approval, establishment registration and product listing, product manufacturing, product labeling, product storage, advertising and promotion, product sales, distribution, recalls and field actions, servicing and post-market clinical surveillance. Unless an exemption applies, each new or significantly modified medical device we seek to commercially distribute in the United States will require either a pre-market notification under Section 510(k) of the U.S. Federal Food, Drug and Cosmetic Act (FDCA), also referred to as a 510(k) clearance, or approval from the FDA through the premarket approval (PMA) process. Both the 510(k) clearance and PMA processes can be lengthy and expensive. We have obtained 510(k) clearance on multiple devices in both Class II and Class III, including our Control IQ technology, the t:slim X2 and Tandem Mobi. In addition, we may be required to obtain a new 510(k) clearance or PMA for significant post-market modifications to our products.

There are three types of interoperable FDA Class II devices (integrated continuous glucose monitoring systems (iCGMs), Alternate Controller Enabled (ACE) insulin pumps, and interoperable automated glycemic controllers (iAGC)) in a complete AID system. The classification of these three device types into Class II is intended to help support continued rapid innovation by streamlining the FDA regulatory pathway for integrated CGM and insulin pumps with advanced algorithms. Our pumps are classified as ACE pumps that are compatible with iCGM devices, and our Control-IQ and Control-IQ+ technologies are classified as an iAGC for people living with type 1 diabetes ages 2 and older. In March 2025, our Control-IQ+ technology was cleared for people living with type 2 diabetes ages 18 and older. In connection with the de novo applications for both the ACE pump and the iAGC category, the FDA established certain special controls that we will need to continue to satisfy. If we are not able to satisfy those special controls, we would be required to seek approval for those products under the traditional PMA submission application, which must be supported by valid scientific evidence that typically includes extensive technical, pre-clinical, clinical, manufacturing and labeling data to demonstrate to the FDA’s satisfaction the safety and efficacy of the device.

Clinical trials are typically required to support a PMA application and are sometimes required for 510(k) clearance. We anticipate that most of our future AID offerings will require supporting clinical data, either from clinical trials or potentially from evidence that we are able to collect through real-world use of our products. These trials generally require submission of an application for an Investigational Device Exemption (IDE) to the FDA. The IDE application must be supported by appropriate data, such as animal and laboratory testing results, showing that it is safe to test the device in humans and that the testing protocol is scientifically sound. Generally, clinical trials for a significant risk device may begin once the IDE application is approved by the FDA, and the study protocol and informed consent are approved by appropriate institutional review boards at the clinical trial sites. The FDA’s approval of an IDE allows clinical testing to go forward, but it does not bind the FDA to accept the results of the trial as sufficient to prove the product’s safety and efficacy, even if the trial meets its intended success criteria.

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Other Regulatory Requirements. Even after a device receives clearance or approval and is placed in commercial distribution, numerous regulatory requirements apply. These include:

•establishment registration and device listing;

•quality management system regulations (QMSR), which requires manufacturers, including third-party manufacturers, to follow stringent design, testing, production, control, supplier/contractor selection, complaint handling, documentation and other quality assurance procedures during all aspects of the manufacturing process;

•labeling regulations that prohibit the promotion of products for uncleared, unapproved or “off-label” uses, and impose other restrictions on labeling, advertising and promotion;

•the FDA’s Medical Device Reporting (MDR) regulations, which require that manufacturers report to the FDA if their device may have caused or contributed to a death or serious injury or malfunctioned in a way that would likely cause or contribute to a death or serious injury if the malfunction were to recur;

•voluntary and mandatory device recalls to address problems when a device is defective and could be a risk to health; and

•corrections and removals reporting regulations, which require that manufacturers report to the FDA field corrections and product recalls or removals if undertaken to reduce a risk to health posed by the device or to remedy a violation of the FDCA that may present a risk to health.

Also, the FDA may require us to conduct post-market surveillance studies or establish and maintain a system for tracking our products through the chain of distribution to the patient level. We are currently conducting a post-market surveillance study for Control-IQ+ technology for users 2-5 years of age. We may elect to pursue additional post-market surveillance studies in the future.

The FDA and the Food and Drug Branch of the California Department of Health Services enforce regulatory requirements by conducting periodic, unannounced inspections and market surveillance. Inspections may include the manufacturing facilities of our subcontractors. If the FDA believes we or any of our contract manufacturers or regulated suppliers are not in compliance with these requirements, it can shut down our manufacturing operations, require recall of our products, refuse to approve new marketing applications, institute legal proceedings to detain or seize products, enjoin future violations, or assess civil and criminal penalties against us or our officers or other employees. Any such action by the FDA would have a material adverse effect on our business. We may be unable to comply with all applicable FDA regulations.

Licensure. To sell our products through the durable medical equipment (DME) channel in the United States, several states require that DME providers be licensed to sell products to patients in that state. Some of these states require that DME providers maintain an in-state location or retain a licensed pharmacist, and in those states, we sell our products through a third-party distributor. Additionally, to sell our products through the pharmacy channel in the United States, we are required to work with intermediaries who have the appropriate pharmacy licenses. Tandem is also registered throughout the United States to issue payment plans. Although we believe we are in material compliance with applicable state regulations regarding licensure requirements, if we were found to be noncompliant, we could be subject to fines and penalties or lose our licensure in that state, which could prohibit us from selling our current or future products to patients in that state. In addition, we are subject to certain state laws regarding professional licensure. We believe that our certified diabetes educators are in material compliance with such state laws. However, if our educators or we were to be found non-compliant in a given state, we may need to modify our approach to providing education, clinical support and customer service.

Fraud and Abuse Laws. There are numerous U.S. federal and state laws pertaining to healthcare fraud and abuse, including the federal Anti-Kickback Statute and the Physician Self-Referral Law (the Stark Law), the federal civil False Claims Act, the federal criminal Health Care Fraud Statute, as well as various state laws regulating healthcare. Our relationships with healthcare providers and other third parties are subject to scrutiny under these laws. Violations of these laws are punishable by criminal and civil sanctions, including, in some instances, imprisonment and exclusion from participation in federal and state healthcare programs, including the Medicare, Medicaid and Veterans Health Administration programs.

Federal Anti-Kickback Statute. The federal Anti-Kickback Statute prohibits persons from knowingly and willfully soliciting, receiving, offering or providing remuneration, directly or indirectly, in cash or in kind, to induce either the referral of an individual, or the furnishing, recommending, or arranging of a good or service, for which payment may be made under a federal healthcare program such as Medicare and Medicaid.

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We provide the initial training to customers necessary for appropriate use of our products either through our own diabetes educators or by contracting with outside diabetes educators who have completed a Tandem pump training course. Outside diabetes educators are reimbursed for their services at fair market value. Although we believe that these arrangements do not violate the Anti-Kickback Statute, regulatory authorities may determine otherwise, especially as enforcement of this law historically has been a high priority for the federal government. Noncompliance with the federal Anti-Kickback Statute could result in our exclusion from Medicare, Medicaid or other governmental programs (which could adversely affect our sales to a material extent), restrictions on our ability to operate in certain jurisdictions, and civil and criminal penalties.

Physician Self-Referral Law. The Stark Law prohibits a physician from referring Medicare or Medicaid patients to an entity providing “designated health services,” including a company that furnishes durable medical equipment, if the physician or their immediate family member has a financial relationship with the company. In addition to statutory exceptions, the Centers for Medicare and Medicaid Services (CMS), has issued numerous regulatory exceptions to the Stark Law. Violation of the Stark Law could result in denial of payment, disgorgement of reimbursements received under a noncompliant arrangement, civil penalties, and exclusion from Medicare, Medicaid or other governmental programs. Although we believe that we have structured our provider arrangements to comply with current Stark Law requirements, these arrangements may not expressly meet the requirements for applicable exception from the law.

Federal False Claims Act. The federal False Claims Act provides, in part, that the federal government may bring a lawsuit against any person whom it believes has knowingly presented, or caused to be presented, a false or fraudulent request for payment from the federal government, or who has made a false statement or used a false record to get a claim approved. In addition, amendments in 1986 to the False Claims Act have made it easier for private parties to bring “qui tam” whistleblower lawsuits under the act. Qui tam actions have increased significantly in recent years, causing greater numbers of healthcare companies to have to defend a false claim action, pay fines and/or be excluded from Medicare, Medicaid or other federal or state healthcare programs as a result of an investigation arising out of such action.

We submit reimbursement claims to federal healthcare programs, and we also may provide some coding and billing information to purchasers of our devices. These activities, if inappropriate, could result in liability under the False Claims Act. Further, claims arising from relationships which violate the Anti-Kickback Statute are considered to be false claims under the False Claims Act. Liability under the False Claims Act may also attach to claims arising from financial relationships which violate the Stark Law. We believe that we currently are in material compliance with the federal government’s laws and regulations concerning the submission of claims and the provision of coding and billing information. However, because we cannot guarantee that the government or qui tam relators will regard any billing errors that may be made as inadvertent, or our provider relationships as compliant, we may have exposure under the False Claims Act.

State Fraud and Abuse Provisions. Many states have also adopted some form of anti-kickback and anti-referral laws and false claims acts. We believe that we are in material conformance to such laws. Nevertheless, a determination of liability under such laws could result in fines and penalties and restrictions on our ability to operate in these jurisdictions.

Health Insurance Portability and Accountability Act of 1996 (HIPAA). HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 (collectively, HIPAA) mandated the adoption of standards for the exchange of electronic health information to encourage overall administrative simplification and enhance the effectiveness and efficiency of the healthcare industry. Ensuring privacy and security of patient information is one of the key factors driving the legislation. If we are found to violate HIPAA, we could be subject to civil or criminal penalties.

HIPAA and Other U.S. Privacy Laws and Regulations. Numerous federal and state laws, rules and regulations govern the collection, dissemination, use, privacy, security and confidentiality of personal information. HIPAA, in addition to the criminal powers above, extensively regulates the use and disclosure of individually identifiable health information, through the Privacy, Security, and Breach Notification Rules. HIPAA requires covered entities, including health plans and most health care providers, to implement administrative, physical and technical safeguards to protect the privacy and security of covered information (known as “protected health information”) and sets limits and conditions on the uses and disclosures that may be made of such protected health information. HIPAA’s Security Rule and certain provisions of the HIPAA Privacy Rule and Breach Notification Rule apply to business associates of covered entities (i.e., entities that provide services to covered entities that may require access and use of protected health information on behalf of covered entities), and business associates are subject to direct liability for violation of these rules. Covered entities must report breaches of unsecured protected health information to affected individuals without unreasonable delay and notification must also be made to the U.S. Department of Health & Human Services, Office for Civil Rights (OCR) and, in certain situations involving large breaches, to the media. The OCR enforces the HIPAA Rules and performs compliance audits and investigations. In addition to enforcement by OCR, HIPAA authorizes state attorneys general to bring civil actions seeking either injunction or damages in response to HIPAA violations that impact state residents.

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On December 1, 2022, OCR issued a bulletin on the requirements under HIPAA for online tracking technologies (e.g., cookies, pixels) to protect the privacy and security of health information. This bulletin outlined OCR’s position on the use of online tracking technology vendors, when certain information received by such vendors constitutes protected health information under HIPAA, and accordingly, when business associate agreements must be executed between covered entities, like us, and such vendors. We are a covered entity under HIPAA and in certain circumstances, we may also be a business associate of another covered entity or of another business associate. There are numerous other laws, regulations and legislative and regulatory initiatives at the federal and state levels addressing privacy and security of personal information. We also remain subject to federal and state privacy-related laws that may be more restrictive or contain different requirements than the privacy regulations issued under HIPAA. These laws vary and could impose additional penalties. Further, certain U.S. states have proposed or enacted comprehensive consumer privacy laws and/or laws governing personal health information, such as the California Consumer Privacy Act, or CCPA. Among other things, these state-specific laws create new data privacy obligations for covered companies and provide new privacy rights to state residents, including the right to opt out of certain disclosures of their information. They may also cause us to incur substantial costs and expenses to ensure ongoing compliance. Various U.S. state laws and regulations may also require us to notify affected individuals and state agencies in the event of a data breach involving individually identifiable information.

In addition to the laws discussed above, we may see more stringent state and federal privacy legislation passed, as the increased cyber-attacks during recent international conflicts have once again put a spotlight on data privacy and security in the U.S. and other jurisdictions. We cannot predict where new legislation might arise, the scope of such legislation, or the potential impact to our business and operations.

Healthcare Fraud. In addition to information security and data privacy obligations, HIPAA also created two new federal crimes: healthcare fraud and false statements relating to healthcare matters. The healthcare fraud statute prohibits knowingly and willfully executing a scheme to defraud any healthcare benefit program, including private payors. A violation of this statute is a felony and may result in fines, imprisonment or exclusion from government sponsored programs. The false statements statute prohibits knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services. A violation of this statute is a felony and may result in fines or imprisonment.

Physician Payments Sunshine Act. The Physician Payments Sunshine Act requires certain manufacturers, including medical device manufacturers, to submit annual data to CMS pertaining to payments or other transfers of value to covered recipients, including physicians (defined to include doctors, dentists, optometrists, podiatrists and chiropractors), other health care professionals (such as physicians assistants and nurse practitioners), and teaching hospitals, as well as information regarding ownership and investment interests held by physicians and their immediate family members. Manufacturers may be subject to audit for their compliance with this law. Failure to submit the required data in an accurate and timely manner may result in the imposition of civil monetary penalties.

Anti-Bribery and Anti-Corruption Laws. The U.S. Foreign Corrupt Practices Act (FCPA), and similar laws in foreign jurisdictions generally prohibit U.S. corporations and their representatives from offering, promising, authorizing or making improper payments, gifts or transfers to any foreign government official to obtain or retain business. The scope of the FCPA would include interactions with certain healthcare professionals and hospital administrators in many countries.

International Regulation

International sales of medical devices are subject to local government regulations, which vary substantially from country to country. The time required to obtain approval in another country may be longer or shorter than that required for FDA approval, and the requirements may differ. There is a trend towards harmonization of quality system standards among the European Union, United States, Canada and various other industrialized countries.

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The regulatory framework governing medical devices is largely harmonized within the European Union (EU), which includes most of the major countries in Europe. Other countries, such as Switzerland, have voluntarily adopted laws and regulations that mirror those of the EU with respect to medical devices. In the EU, medical devices are governed by Regulation (EU) 2017/745 on medical devices (MDR), which entered into application on May 26, 2021, repealing and replacing both Directive 93/42/EEC concerning medical devices (MDD) and Directive 90/385/EEC concerning active implantable medical devices (AIMDD). The MDR and its associated guidance documents and harmonized standards regulating the design, development, preclinical and clinical performance premarket conformity assessment, registration, manufacture, labeling storage, claims, sales and distribution, export and import and post-market surveillance, vigilance, and market surveillance for medical devices. To be placed on the EU market, devices must undergo a conformity assessment and bear the CE mark, indicating that the device conforms to the requirements of the MDR. In particular, medical devices must comply with the General Safety and Performance Requirements (GSPRs), set out in Annex I of the MDR. Compliance with these requirements is a prerequisite to affixing the CE mark to devices, without which they cannot be marketed or sold in the European Economic Area (comprised of the 27 EU Member States, Iceland, Liechtenstein and Norway). To demonstrate compliance with the GSPRs and obtain the right to affix the CE mark, medical devices manufacturers must conduct a conformity assessment procedure, which varies according to the type of medical device and its classification. Apart from low-risk medical devices (Class I with no measuring function and which are not sterile), a conformity assessment procedure requires review by a Notified Body. Depending on the relevant conformity assessment procedure, the Notified Body audits and examines the technical documentation and the quality system for the manufacture, design and final inspection of the medical devices. The Notified Body issues a CE Certificate of Conformity following successful completion of a conformity assessment procedure conducted in relation to the medical device and its manufacturer and their conformity with the GSPRs. This Certificate and completion of the related conformity assessment process entitles the manufacturer to affix the CE mark to its medical devices after having prepared and signed a related EU Declaration of Conformity. The MDR provides transitional provisions which, under strict conditions, permit manufacturers to continue to place medical devices on the market on the basis of CE Certificates of Conformity issued by Notified Bodies in accordance with the MDD or the AIMD until December 31, 2027 or December 31, 2028 depending on the risk classification.

Outside of the EU, regulatory approval needs to be sought on a country-by-country basis for us to market our products. Other countries have adopted medical device regulatory regimes, such as Health Canada’s risk classification system for invasive devices, among others. Each country may have its own processes and requirements for medical device licensing, approval, and regulation, therefore requiring us to seek regulatory approvals on a country-by country basis.

Internationally, a range of anti-bribery and anti-corruption laws, as well as some industry-specific laws and codes of conduct, apply to the medical device industry and interactions with government officials and entities and healthcare professionals. Further, the EU member countries have emphasized a greater focus on healthcare fraud and abuse and have indicated greater attention to the industry by the European Anti-Fraud Office. The Code of Ethical Business Practices became effective on January 1, 2017. Increasingly stringent data protection and privacy rules have had and will continue to have substantial impact on the use of patient data across the healthcare industry. The European Union’s General Data Protection Regulation (EU GDPR) and the United Kingdom’s General Data Protection Regulation (UK GDPR) (collectively, GDPR) applies across the EU and includes, among other things, a requirement for prompt notice of data breaches to data subjects and supervisory authorities in certain circumstances and significant fines for noncompliance. Noncompliance could result in the imposition of fines, penalties, or orders to stop noncompliant activities. Due to the strong consumer protection aspects of GDPR, companies subject to its purview are allocating substantial legal costs to the development of necessary policies and procedures and overall compliance efforts. Data transfer risk remains a potential issue that requires regular monitoring. Certain governments around the world are also adopting laws and regulations pertaining to mandatory corporate sustainability reporting.

Environment, Social and Governance

Our Board of Directors and management team believe that environmental stewardship, social responsibility, and solid corporate governance are important to our business strategy and long-term value creation for our shareholders, employees, customers, and communities. The Audit Committee of our Board oversees ESG matters across our business operations in accordance with its charter. Our management team is responsible for developing and driving strategic ESG initiatives and programs across our business and providing regular updates on progress to the Audit Committee.

Additional information about our Environmental, Social and Governance practices as well as our Sustainable Business Report can be found on our website within the “Investor Center” section. The information contained on or accessed through our website does not constitute part of this Annual Report, and references to our website address in this Annual Report are inactive textual references only.

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Human Capital

We are committed to creating and maintaining a safe, diverse, and inclusive community for all employees while we serve our customers and fulfill our mission to improve the lives of people with diabetes. As of December 31, 2025, we had approximately 2,500 regular full-time employees, who primarily work in the United States, Canada, or Europe. The term “employees” in this Annual Report means our regular full-time employees. Our headquarters are in San Diego, California, where our primary research and development and administrative functions are located, and where we also operate a manufacturing facility and a warehousing facility. None of our employees are represented by a collective bargaining agreement, and we have never experienced any work stoppage. We believe we have good relations with our employees.

Culture

Fostering and maintaining a strong, healthy culture is a key strategic focus. Our core values statement was created by our employees in a bottom-up, cross-functional process that we revisit and refresh on a periodic basis. Our Words We Live By describe our core values and reflect who we are and the way our employees interact with one another, our customers, partners and stockholders.

We focus on cultivating and encouraging an inclusive and equitable culture where diversity of thought is represented and can thrive throughout our organization. We believe that bringing together different perspectives and experiences is fundamental to innovation and continuing to raise the bar in the field of diabetes technology. Moreover, we are focused on cultivating and supporting our internal culture through diversity of thought, support and advocacy within the diabetes community and continuing to build and maintain a diverse and inclusive workforce.

Organizational Development

Attracting, developing and retaining employees is critical to our longer-term success. We have established a comprehensive training program to develop employees throughout the organization. Emerging Leaders and Leading in Tandem are examples of internal programs intended for high performing individual contributors, and newly hired and promoted supervisors and managers, respectively. More than 94% of employees participating in these programs remained employed at Tandem as of December 31, 2025 and approximately 14% had been promoted or had a significant change in scope of responsibility. In 2025, more than 200 employees participated in our leadership development programs.

Competitive Total Rewards

Our compensation program is designed to align employee compensation with our performance and to provide the proper incentives to attract, retain, and motivate employees to achieve superior results. The structure of our compensation program balances incentive earnings for both short-term and long-term performance.

•We provide employee wages that are competitive and consistent with employee positions, skill levels, experience, knowledge, and geographic location.

•We engage internationally recognized outside compensation and benefits consulting firms to independently evaluate the effectiveness of our executive compensation and benefit programs and to provide benchmarking.

•We align our executives’ long-term equity compensation with our stockholders’ interests.

•Annual increases and incentive compensation are based on Company performance as well as each individual’s contribution to the Company’s achieved results and are documented through our talent management procedures as part of our annual review process.

To foster a stronger sense of ownership and align the interests of partners with stockholders, equity awards are provided to a portion of our employees in line with benchmark practices under our broad-based stock incentive programs. Also, our full-time U.S. employees are able to participate in our employee stock purchase program. Furthermore, we offer comprehensive, locally relevant and innovative benefits to all eligible employees, including health insurance, paid time off, paid and unpaid leaves, defined-contribution retirement plans, health savings accounts, flexible spending accounts, life and disability coverage, voluntary accident, critical illness, legal and identity theft coverage, employee discount programs, and an employee loaner pump program.

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Employee Health and Safety

The health and safety of our employees is our highest priority, and this is consistent with our operating philosophy. We have integrated our employee health and safety efforts with our human resources functions to create a corporate culture with a shared commitment to the well-being of our professionals. Our employee assistance and wellness programs offer a range of benefits and services. For example, as a benefit to our employees and their eligible dependents, we provide access to personal and job-related counseling and assistance resources for addressing concerns such as emotional well-being, family and relationships, legal and financial matters, healthy lifestyles, mental health, substance abuse, and work and life transitions.

We have comprehensive safety training programs that teach our employees how to do their jobs safely and in compliance with laws and regulations. We operate in modern, efficient, and safe facilities, and have had minimal accident and injury rates company-wide. Despite this success, our goal remains the same: zero accidents.

Additional Information

Our website address is www.tandemdiabetes.com. Copies of our filings with the SEC, including our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), are available free of charge on our website within the “Investor Center” section as soon as reasonably practicable after having been electronically filed with or furnished to the SEC. The information contained on or accessed through our website does not constitute part of this Annual Report, and references to our website address in this Annual Report are inactive textual references only.