NEPHROS INC

Item 1. Business Overview

Nephros is a commercial-stage company that develops and markets high-performance water filtration solutions for points of use, with a core focus on medical-grade water filtration. Our medical filtration portfolio includes two product lines: infection control and dialysis water. The infection control segment features both microfilters (0.1 micron), which retain bacteria, and ultrafilters (0.005 micron), which retain bacteria, viruses, and endotoxins to address a broader spectrum of waterborne pathogens including and beyondLegionella andPseudomonas. The dialysis segment consists exclusively of ultrafilters, extending the same microbial and endotoxin retention capabilities to the purification of water and bicarbonate concentrate used in dialysis treatment, where endotoxin control is especially critical. All of our medical-grade filters are FDA 510(k)-cleared as Class II medical devices—a distinguishing feature that affirms their validated safety and performance in critical-use environments. While these filters are widely used in healthcare settings, they have also been adopted across a range of other industries—including manufacturing, laboratories, aviation, and federal facilities—where water purity is essential to operational safety and compliance.

In addition, we offer a line of commercial water filters that improve taste and odor, reduce biofilm formation and scale buildup, and remove cysts, particulates, and lead from water systems. With the recent release of our newest solution, validated for the reduction of Total PFAS (a mixture of seven PFAS compounds including PFOA, PFOS, PFHxS, PFNA, PFHpA, PFBS, and PFDA), our portfolio of products is further enhanced with the ability to address a broad spectrum of emerging and persistent waterborne contaminants. Our commercial filtration products are broadly applicable across industries and are especially valuable when used in tandem with our medical-grade filters to deliver comprehensive water-quality protection. Whether in clinical care, industrial operations, or public infrastructure, Nephros solutions support the universal need for safe, high-quality water.

Our Products

We develop and sell point-of-use water filtration products used in both medical and commercial applications. Our water filtration products employ multiple filtration technologies, as described below.

For medical applications, we manufacture both ultra- and microfilters using polysulfone hollow fiber membranes that retain microbiological contaminants through physical size exclusion. Our ultrafilters, with a 0.005-micron pore size, retain bacteria, viruses, and endotoxins, provide a unique alternative to charged membrane solutions and feature one of the smallest pore sizes available. Our microfilters, with a 0.1-micron pore size, also retain bacteria, a critically important function given the prevalence ofLegionella in premise plumbing and the risks associated with Legionnaires’ disease. Across both filter types, Nephros filters are distinguished by exceptional membrane surface area and longer service life, particularly in comparison to our competitors, making Nephros filters well-suited to support improved water safety within the demands of highly regulated environments.

Our primary sales strategy for medical applications is to sell within healthcare through distributors (also termed as value-added resellers, or “VARs”). Leveraging VARs has enabled us to rapidly expand our access to target customers with limited sales staff expansion. In addition, while we are currently focused on healthcare as a primary customer base, the VARs that support these facilities also support a wide variety of commercial and industrial businesses. We believe that our VAR relationships have and will continue to facilitate growth in filter sales outside of the medical industry. In addition to VARs, we also utilize a direct salesforce that targets key geographic regions throughout the country, while focusing on the hospital and dialysis customers.

For commercial applications, we develop filters to improve water quality through the reduction of aesthetic and functional contaminants. This segment includes both carbon-based and carbon-free solutions to reduce a number of issues including taste, odor, scale buildup, fine particulate, lead, cysts, and Total PFAS (otherwise known as “forever chemicals”). Like our infection control segment, our commercial filters support a wide range of applications; they also play a key role in enhancing equipment performance and reducing maintenance needs.

Our commercial application sales model also combines both direct and indirect channels. Through our internal sales team, we sell directly to customers across a range of industries, including healthcare, where our commercial solutions are an effective complement to our medical-grade, infection control filters. We also partner with VARs, including one non-exclusive partner focused only on food service and hospitality sectors, such as quick-service restaurants (QSRs), convenience stores, and restaurants. In contrast to our channel partners who offer both medical and commercial products, this VAR expands our reach in high-volume, commercial food and beverage markets.

Target Markets

We currently serve the following primary and emerging markets through our portfolio of medical-grade and commercial water filtration products:

Additional Use Cases

Beyond healthcare and foodservice settings, Nephros filters are also deployed in laboratories, manufacturing facilities, aviation environments, and government buildings, where water purity is critical to safety, compliance, or system performance. With the recent addition of Total PFAS reduction capability, we also anticipate growing relevance in schools and other federally regulated facilities, where adherence to standards such as the Safe Drinking Water Act is a key consideration. We continue to evaluate opportunities to expand into new verticals where our filtration technologies provide measurable value.

Hospitals and Other Healthcare Facilities. Nephros infection control filters are a leading tool for proactive protection to patients in high-risk areas (e.g., ice machines, surgical rooms, NICUs) and reactive protection to patients in broader areas during periods of water pathogen outbreaks. Our products are used in hundreds of medical facilities to aid in infection control, both proactively and reactively.

According to the American Hospital Association’s most recent annual survey data (2023), there are approximately 6,093 hospitals in the U.S., representing more than 913,000 beds and approximately 34.4 million inpatient admissions annually. These facilities rely on extensive internal water systems to support patient care, including handwashing, bathing, medical device reprocessing, dialysis, and other clinical and operational uses.

According to a June 2025 report from the U.S. Centers for Disease Control and Prevention (“CDC”), on any given day, approximately one in 31 hospitalized patients has at least one healthcare-associated infection (“HAI”), underscoring the scale of infection risk within hospital environments. The CDC further identifies waterborne pathogens such asLegionella,Pseudomonas, and nontuberculous mycobacteria as significant contributors to HAIs, noting that these organisms can proliferate in aging, complex premise plumbing systems commonly found in healthcare facilities and be transmitted through sinks, showers, ice machines, and other water outlets.

CDC surveillance of waterborne disease outbreaks indicates that premise plumbing is a leading source of water-related illness, hospitalizations, and deaths in the United States, with healthcare facilities representing a higher-risk environment due to susceptible patient populations and frequent water exposure. These factors underscore the importance of effective water management and point-of-use filtration strategies to mitigate microbiological risk in critical-use healthcare settings.

Since 2017, Centers for Medicare and Medicaid Services (“CMS”) has required Medicare- and Medicaid-certified healthcare facilities to implement policies and procedures to reduce the risk of growth and spread of Legionella and other opportunistic waterborne pathogens in building water systems. Compliance with these expectations is evaluated through routine survey and certification activities, during which CMS surveyors and accrediting organizations review whether facilities have established and implemented formal water management programs (“WMPs”), including documented governance, monitoring protocols, corrective actions, and records demonstrating ongoing execution. CMS guidance directs facilities to align their WMPs with prevailing industry standards, including ASHRAE Standard 188 and the Centers for Disease Control and Prevention (“CDC”) water management toolkit. While the underlying CMS expectations have remained in effect since 2017, enforcement and documentation requirements have become increasingly embedded in standard survey practice over time, particularly as healthcare facilities have faced heightened scrutiny of waterborne infection risks. We believe that continued enforcement of these requirements and the growing emphasis on effective water management programs may have a positive impact on demand for our HAI-inhibiting micro- and ultrafilters.

Nephros filters are validated for physical retention of bacteria, viruses, and endotoxins through size exclusion. All models are FDA 510(k)-cleared and installed at the point of use, where they can support compliance goals, align with evolving standards, and provide additional protection for patients, staff, and visitors.

Dialysis Settings. Nephros dialysis water filters are widely deployed in both acute and chronic dialysis environments to enhance water safety and support the production of ultrapure dialysate. Our solutions provide retention of bacteria, viruses, and endotoxins in water and bicarbonate lines used to treat patients with kidney failure.

Hemodialysis requires the use of large volumes of purified water, often more than 100 liters per treatment. Clinics rely on reverse osmosis systems to generate this water and use ultrafilters downstream as a final barrier against microbial contaminants. Our filters are used in both fixed RO loops and portable systems and are validated for up to 12 months of service life in dialysis applications.

To perform hemodialysis, dialysis clinics rely on dedicated water purification systems to produce ultrapure water and bicarbonate concentrate, the two essential ingredients for preparing dialysate, the fluid used to remove waste material from the blood during treatment. As of early 2025, there are approximately 7,556 dialysis clinics in the United States serving more than 500,000 patients. While precise counts of hemodialysis machines in use are not publicly reported on a routine national basis, industry sources indicate that the installed base in the United States likely exceeds 200,000 hemodialysis units, consistent with estimates used in market analyses. These dialysis facilities and machines represent a significant sustained demand environment for water purification and treatment technologies that support patient safety and the reliable operation of clinical dialysis care.

Nephros dialysis filters are validated for physical retention of bacteria, viruses, and endotoxins through size exclusion. All models are FDA 510(k)-cleared and installed within dialysis water systems, where they support the production of ultrapure water and bicarbonate concentrate used in hemodialysis treatment.

Foodservice and Hospitality. Our commercial product portfolio includes both carbon-based and carbon-free filtration solutions that address a variety of water-quality concerns common in foodservice and hospitality industries. These include but are not limited to taste and odor compounds, scale-forming minerals, and various particulates, with several membrane-based models capable of retaining particles down to 0.005 micron. In addition, our newest offering supports the validated reduction of Total PFAS, expanding our reach to customers concerned with long-term exposure to “forever chemicals” in water-fed equipment.

Over time, we believe that the same water safety management programs currently underway at medical facilities may migrate to commercial markets. As the epidemiology of waterborne pathogens expands, links to contamination sources will become more efficient and the data more readily available. In cases where those sources are linked to restaurants, hotels, office buildings and residential complexes, the owners of those facilities may face increasing liability exposure. We expect that building owners will come to understand ASHRAE-188, which outlines risk factors for buildings and their occupants, and provides water safety management guidelines. We believe, in time, most commercial buildings will need to follow the basic requirements of ASHRAE-188: create a water management plan, perform routine testing, and establish a plan to treat the building in the event of a positive test.

As demand for water testing and microbiological filtration grows, we intend to be ready to deploy our expertise and solutions based on our years of experience servicing the medical market. We believe that we have an opportunity to offer unique expertise and products to the commercial market.

Corporate Information

We were incorporated under the laws of the State of Delaware in April 1997. Our principal executive offices are located at 380 Lackawanna Place, South Orange, New Jersey 07079, and our telephone number is (201) 343-5202. We also have an office in Whippany, New Jersey. For more information about Nephros, please visit our website atwww.nephros.com. We are not including the information on our website as a part of, nor incorporating it by reference into, this Annual Report on Form 10-K.

Manufacturing and Suppliers

We do not, and do not intend to in the near future, manufacture any of our medical device filtration products. We do manufacture some of our commercial filtration products in our facility in South Orange, New Jersey.

In April 2012, we entered into a License and Supply Agreement (as thereafter amended, the “License and Supply Agreement”) with Medica S.p.A. (“Medica”), an Italy-based medical product manufacturing company, for the marketing and sale of certain filtration products based upon Medica’s proprietary Medisulfone ultrafiltration technology in conjunction with the Company’s filtration products, and for an exclusive supply arrangement for the filtration products. Under the License and Supply Agreement, as amended, Medica granted us an exclusive license, with right of sublicense, to market, promote, distribute, offer for sale and sell the filtration products worldwide, with certain limitations on territory, during the term of the License and Supply Agreement. In addition, the Company granted to Medica an exclusive license under the Company’s intellectual property to make the filtration products during the term of the License and Supply Agreement. The filtration products covered under the License and Supply Agreement include both certain products based on Medica’s proprietary Versatile microfiber technology and certain filtration products based on Medica’s proprietary Medisulfone ultrafiltration technology. In November 2025, the Company signed a new agreement with Medica which extends the term until December 31, 2030, unless earlier terminated by either party in accordance with the terms of the License and Supply Agreement. In exchange for the rights granted, the Company has agreed to make minimum annual aggregate purchases from Medica of €4,976,000, €5,349,000, €5,750,000, €6,000,000 and €6,300 ,000 for the years 2026, 2027, 2028, 2029 and 2030 , respectively. Under the November 2025 agreement, we have agreed to pay interest per month at the EURIBOR 360-day rate plus 500 basis points calculated on the principal amount of any outstanding invoices that are overdue by more than 15 days beyond the original payment terms. The Company has the right to terminate the License and Supply Agreement for convenience upon 90 days’ prior written notice. Medica may terminate the License and Supply Agreement upon written notice if the Company fails to cure a monetary breach thereunder within 30 days after Medica provides written notice thereof to the Company. Either the Company or Medica may terminate the License and Supply Agreement if the other party is in material breach and such breach is not cured within the specified cure period. Additionally, either the Company or Medica may terminate the License and Supply Agreement in the event of specified insolvency events involving the other party.

Sales and Marketing

Our New Jersey headquarters oversees global sales and marketing activity of our ultrafilter products. We work with multiple distributors for our ultrafilter products in the hospital and dialysis water markets. For the foodservice and hospitality markets, as discussed above, we had contracted with Donastar LLC as our exclusive distributor. Effective September 2024, we ended our exclusive relationship with Donastar. Although Donastar continues to distribute our products on a non-exclusive basis, we are broadening our market reach through new distributor relationships. For other prospective markets for our ultrafilter products, we are pursuing alliance opportunities for joint product development and/or distribution. Our ultrafilter manufacturer in Europe shares certain intellectual property rights with us for one of our dual stage ultrafilter designs.

Research and Development

Our research and development efforts continue on several fronts directly related to our current product lines. For the ultrafiltration systems business, we are continually working with existing and potential distributors of ultrafilter products to develop solutions to meet customer needs.

Major Customers

For the years ended December 31, 2025 and 2024, the following customers accounted for the following percentages of our revenues, respectively:

As of December 31, 2025 and 2024, the following customer accounted for the following percentage of our accounts receivable:

Competition

With respect to the water filtration market, we compete with companies that are well-entrenched in the water filtration domain. These companies include Cytiva (formerly Pall Corporation), Aquatools, Aquamedix, and i3 for medical / microbiological filtration, and 3M Company and Pentair for commercial water-quality filtration. Our methods of competition in the water filtration domain include:

Intellectual Property

Patents

We protect our technology and products through patents and patent applications. In addition to the United States, we also apply for patents in other jurisdictions, such as the European Patent Office, Canada, and Japan, to the extent we deem appropriate. We have built a portfolio of patents and applications covering our products, including their hardware design and methods of hemodiafiltration.

We believe that our patent strategy will provide a competitive advantage in our target markets, but our patents may not be broad enough to cover our competitors’ products and may be subject to invalidation claims. Our U.S. patent for the “Method and Apparatus for a Hemodiafiltration Module for use with a Dialysis Machine,” has claims that cover the OLpūr MDHDF filter series and the method of hemodiafiltration employed in the operation of the products. Technological developments in end stage renal disease (“ESRD”) therapy could reduce the value of our intellectual property. Any such reduction could be rapid and unanticipated. We have issued patents on our water filtration products and applications in process to cover various applications in residential, commercial, and remote environments.

As of December 31, 2025, we had five U.S. patents and one Canadian patent.

Trademarks

As of December 31, 2025, in the United States, we secured registrations of the trademarks ENDOPUR, HYDRAGUARD, NANOGUARD, and NEPHROS. In the U.S., we filed one trademark application for BECAUSE WATER MATTERS. In the U.K., we secured registrations for the trademarks NANOGUARD, and NEPHROS HYDRAGUARD.

Governmental Regulation

The research and development, manufacturing, promotion, marketing, and distribution of our medical filtration products in the United States and other regions of the world are subject to regulation by numerous governmental authorities, including the FDA and analogous agencies.

United States

The FDA regulates the manufacture and distribution of medical devices in the United States pursuant to the Food, Drug, and Cosmetics (FDC) Act. Our medical filtration products are regulated in the United States as medical devices by the FDA under the FDC Act. Under the FDC Act, medical devices are classified into one of three classes, namely Class I, II or III, on the basis of the controls deemed necessary by the FDA to reasonably ensure their safety and effectiveness.

Before a new medical device can be introduced to the market, Section 510(k), and Section 515 of the FDC Act require a manufacturer who intends to market a medical device to submit a premarket notification (Section 510(k)) or a request for premarket approval (Section 515), to the FDA.

A 510(k) clearance will be granted if the submitted information establishes that the proposed device is “substantially equivalent” to a legally marketed Class I or Class II medical device or to a Class III medical device for which the FDA has not called for premarket approval under Section 515. The 510(k)-clearance process is generally faster and simpler than the premarket approval process.

Premarket approval (PMA) is the FDA’s process of scientific and regulatory review to evaluate the safety and effectiveness of Class III medical devices. Class III devices are those that support or sustain human life, are of substantial importance in preventing impairment of human health, or which present a potential, unreasonable risk of illness or injury, or are new and present unknown safety or effectiveness issues or risks. PMA is the most stringent type of device marketing application required by the FDA. To gain approval, the manufacturer must present adequate scientific evidence to assure that the device is safe and effective for its intended use(s).

For any devices cleared through the 510(k)-clearance process, modifications or enhancements that could significantly affect the safety or effectiveness of the device or that constitute a major change to the intended use of the device will require a new 510(k) clearance submission. Accordingly, for any of our medical filtration products cleared through the Section 510(k) clearance process, we are required to submit an additional Section 510(k) notification if subsequent modifications or enhancements could significantly affect a product’s safety or effectiveness or constitute a major change to its intended use.

All of our medical filtration products currently marketed in the United States are regulated by the FDA as Class II medical devices and have received FDA 510(k) clearance for their intended uses. Our FDA-cleared portfolio includes ultrafiltration designed for purification of dialysis water, as well as ultrafiltration and microfiltration technologies for filtration of EPA-quality water to aid in infection control at the point of use. In addition, we hold FDA clearances for certain products and technologies that are not currently commercialized, which may support future development, partnerships, or strategic initiatives.

The FDC Act requires that medical devices be manufactured in accordance with the FDA’s current QSR regulations which require, among other things, that:

In addition to the requirements described above, the FDC Act requires that:

We and our contract manufacturers are required to manufacture our products in compliance with current Good Manufacturing Practice (GMP) requirements set forth in the QSR. The QSR requires a quality system for the design, manufacture, packaging, labeling, storage, installation, and servicing of marketed devices, and it includes extensive requirements with respect to quality management and organization, device design, buildings, equipment, purchase and handling of components or services, production and process controls, packaging and labeling controls, device evaluation, distribution, installation, complaint handling, servicing, and record keeping. The FDA evaluates compliance with the QSR through periodic unannounced inspections that may include the manufacturing facilities of our subcontractors. If the FDA believes that we or any of our contract manufacturers, or regulated suppliers, are not in compliance with these requirements, there may be a material adverse effect on our manufacturing operations, affecting our ability to sell.

Regulatory Authorities in Regions Outside of the United States

We have obtained regulatory approvals to market certain medical filtration products outside of the United States, including in Canada and Brazil. Regulatory requirements for medical devices vary significantly by country and may range from minimal oversight to comprehensive pre-market review and post-market compliance obligations similar to those required by the FDA.

Our manufacturing facilities are subject to audits and certified to ISO 13485:2016, the international quality management standard for medical device manufacturers, which supports regulatory compliance and product distribution in multiple jurisdictions, including the United States and Canada.

We participate in the Medical Device Single Audit Program (MDSAP), which allows for a single regulatory audit of a medical device manufacturer’s quality management system that satisfies the requirements of multiple regulatory authorities. In November 2020, we received MDSAP certification supporting continued compliance regulatory compliance and the ongoing marketing of approved products in the United States and Canada. In November 2023, our MDSAP certification was expanded to include Brazil, enabling the marketing of select medical filtration products in that market in accordance with applicable regulatory approvals.

Product Liability and Insurance

The production, marketing and sale of our products have an inherent risk of liability in the event of product failure or claim of harm caused by product operation. We have acquired product liability insurance for our products in the amount of $3 million. A successful claim in excess of our insurance coverage could materially deplete our assets. Moreover, any claim against us could generate negative publicity, which could decrease the demand for our products, our ability to generate revenues and our profitability.

Some of our existing and potential agreements with manufacturers of our products and components of our products do or may require us (1) to obtain product liability insurance or (2) to indemnify manufacturers against liabilities resulting from the sale of our products. If we are not able to maintain adequate product liability insurance, we will be in breach of these agreements, which could materially adversely affect our ability to produce our products. Even if we are able to obtain and maintain product liability insurance, if a successful claim in excess of our insurance coverage is made, then we may have to indemnify some or all of our manufacturers for their losses, which could materially deplete our assets.

Employees

As of December 31, 2025, we employed a total of 36 full-time employees, including 12 employed in sales/marketing/customer support, 17 in logistics, quality, general, and administrative, and 6 in research and development and 1 in manufacturing. None of our employees are currently represented by a labor union or covered by a collective bargaining agreement and we believe that our relations with our employees are good. During 2025, we had limited voluntary turnover. Going forward, we intend to focus on maintaining our current good relations with our employees and continuing to develop and explore ways to collaborate with our employees and create a well-regarded workplace.

Available Information

We are subject to the reporting requirements of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). The Exchange Act requires us to file periodic reports, proxy statements and other information with the SEC. The SEC maintains a website that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC. These materials may be obtained electronically by accessing the SEC’s website athttp://www.sec.gov.