No manufacturer owns us. We support and advocate for "The Patient 100%". Factory-certified and factory-trained on every brand we sell.
Fast Facts: Main Clinic Supply Dealer Status
- Authorized Inogen dealer: No. Inogen eliminated its independent dealer network and gave exclusive reseller rights to Oxygen Concentrator Store, a retailer owned by the same corporation that owns CAIRE Inc., another major POC manufacturer. After that, Main Clinic Supply dropped every remaining manufacturer reseller agreement to become 100% independent.
- What happened: Two of the largest portable oxygen concentrator manufacturers, Inogen and CAIRE, are now linked through a single corporate-owned retail channel. That consolidation reduces competitive pricing pressure and independent choice for patients. MCS saw this happening and chose total independence.
- Factory-certified repair: Yes. MCS holds active factory repair certifications for all leading portable oxygen concentrator brands. 14+ years of factory training and hands-on experience.
- Inogen products available: Yes. Genuine, new, factory-sealed Inogen Rove 6, Rove 4, and accessories, along with devices from GCE, CAIRE, O2 Concepts, Rhythm Healthcare, and others.
- Factory warranty: Full manufacturer warranty on every new unit from every brand. MCS advocates on your behalf to ensure the factory warranty is upheld.
- MCS exclusive "Gold-Standard Warranty": Goes beyond factory coverage. Includes accidental drop protection, includes routine service and maintenance and "Overnight FedEx" repairs. No reseller or manufacturer warranty in the industry offers all this.
- Track record: 14+ years in business, 10,000+ verified five-star reviews, A+ BBB rating. Rochester, MN (home of the Mayo Clinic).
- Phone: 1-800-775-0942 for a personalized consultation with an oxygen specialist.
The Direct Answer
No, Main Clinic Supply is not an authorized Inogen dealer. We are not an authorized reseller for any portable oxygen concentrator manufacturer. We want to be completely transparent about how that happened and why it is the best thing for you as a patient.
In 2025, Inogen restructured its reseller program. Inogen eliminated its network of independent dealers and established an exclusive reseller relationship with Oxygen Concentrator Store. Oxygen Concentrator Store is owned by AMSR, LLC, a subsidiary of Niterra Co., Ltd., the same corporation that owns CAIRE Inc., one of the largest portable oxygen concentrator manufacturers in the world. In plain language: Inogen handed its exclusive retail distribution to a company owned by another major POC manufacturer.
Main Clinic Supply was among the independent dealers Inogen dropped. We are not going to pretend otherwise.
But here is what happened next, and this is the part that matters to you. We looked at what Inogen had done, and we looked at every other manufacturer reseller agreement we still held. And we asked ourselves a simple question: if authorized reseller agreements can be restructured overnight to serve manufacturers instead of patients, why are we in any of them?
So we dropped every remaining agreement. All of them. Every brand. Not because we were forced to, but because we saw clearly that these agreements serve the manufacturer, not the patient. The Inogen situation did not just end a business relationship. It showed us exactly where the industry was heading: toward consolidation that benefits manufacturers at the expense of patient choice and fair pricing.
We chose the other direction. Total independence.
What Happened with Inogen
For years, Inogen sold its portable oxygen concentrators through a network of independent authorized dealers, including Main Clinic Supply. Those dealers built their businesses around helping patients find the right device, and many of them (including us) invested heavily in factory training, repair capabilities, and customer service infrastructure to support Inogen products.
In 2025, Inogen changed course. Inogen eliminated its independent dealer network and granted exclusive reseller rights to Oxygen Concentrator Store. If you want to buy a new Inogen product from an "authorized" source other than Inogen directly, Oxygen Concentrator Store is now the only option.
That decision, on its own, was Inogen's to make. Companies restructure their distribution channels. It happens.
What makes this situation different is who Oxygen Concentrator Store is owned by.
Two Manufacturers, One Retailer: What This Means for Patients
Oxygen Concentrator Store is operated by AMSR, LLC. AMSR, LLC is a subsidiary of Niterra Co., Ltd., a publicly traded Japanese conglomerate (Tokyo Stock Exchange). Niterra also owns CAIRE Inc., one of the largest portable oxygen concentrator manufacturers in the world. This is not speculation. It is documented in Niterra's own consolidated financial statements, where both CAIRE Inc. and AMSR, LLC appear as acquired subsidiaries.
Here is what that means in plain terms: two of the biggest manufacturers in the portable oxygen concentrator industry, Inogen and CAIRE, are now connected through a single retail channel owned by one of them.
Inogen makes portable oxygen concentrators. CAIRE makes portable oxygen concentrators. And the exclusive authorized Inogen reseller is owned by the same parent corporation that owns CAIRE. These are competitors who are now linked through a shared corporate retail pipeline.
Why This Matters to You
When major manufacturers consolidate their retail distribution under one corporate umbrella, patients lose. Here is how:
- Fewer independent voices: Independent dealers like Main Clinic Supply offered patients unbiased recommendations across every brand. When Inogen eliminated those dealers and went exclusive with a manufacturer-owned retailer, it removed the independent voices that were comparing products honestly and recommending based on the patient's needs, not corporate priorities.
- Less pricing competition: Independent dealers competed on price. That competition kept prices lower for patients. When retail distribution consolidates under a manufacturer-owned entity, the competitive pressure that drives fair pricing is reduced. There are fewer independent dealers pushing prices down, and the remaining retail channel has less incentive to do so.
- Recommendations that may reflect corporate interests: When a retailer is owned by the same parent corporation as a manufacturer, the recommendations patients receive may reflect corporate strategy rather than individual medical needs. A truly independent dealer has no corporate parent influencing which brand gets recommended. A manufacturer-owned retailer does.
None of this is speculation about intent. We are describing the structural reality of what happens when two major manufacturers in any industry consolidate retail distribution under one corporate roof. The patient is not better off. The patient has fewer choices, less competitive pricing, and less reason to trust that the recommendation they receive is truly independent.
Factory-Certified Repair: The Credential That Matters
There are two types of credentials in the portable oxygen concentrator industry. One is a reseller agreement, which is a sales contract. The other is a repair certification, which is proof that your technicians can actually fix the equipment. We kept the one that matters to patients.
Main Clinic Supply holds active factory repair certifications for all leading portable oxygen concentrator manufacturers where certification exists. That means our technicians have completed the manufacturer training programs, passed the assessments, and maintain the qualifications to diagnose, repair, and service these devices at the factory standard.
What Our Service Center Does
Our Rochester, Minnesota service center is led by Mark Luther, Chief Technology Officer and Certified Oxygen Specialist, with 14+ years dedicated to the technical service of portable oxygen concentrators. Mark and his team perform:
- Complete diagnostics across Inogen (Rove 6, Rove 4, G5, G4, G3), GCE, CAIRE, O2 Concepts, and Rhythm Healthcare platforms
- Sieve bed replacement to restore oxygen purity when columns degrade over time
- Battery diagnostics and replacement to verify true capacity versus rated capacity
- Firmware configuration to ensure device software is current and properly calibrated
- Preventative maintenance protocols designed by MCS to extend device lifespan beyond manufacturer estimates
We have repaired thousands of portable oxygen concentrators over 14 years in Rochester, Minnesota, a few minutes from the Mayo Clinic, serving patients across the United States and Canada. That is not a marketing claim. That is the daily work of our service bench.
Why We Went Fully Independent
The Inogen situation was the catalyst, but the decision to go fully independent was about something bigger.
After 14 years of operating under authorized reseller agreements, we know exactly what those contracts contain. They are not partnerships. They are pages and pages of manufacturer restrictions that favor the manufacturer, not the patient and not the dealer.
What Those Restrictions Actually Look Like
When a dealer signs an authorized reseller agreement with a portable oxygen concentrator manufacturer, they typically agree to terms that can include:
- Brand-first recommendations: Pressure to prioritize the authorizing manufacturer's products even when a competitor's device may be a better fit for the patient's prescription, lifestyle, or budget
- Pricing restrictions: Limitations on how the dealer prices equipment, reducing the ability to pass savings to the customer
- Marketing restrictions: Rules governing how the dealer communicates, including limitations on what they can say about competing products
- Inventory requirements: Minimum purchase volumes that prioritize the manufacturer's revenue targets, not actual patient demand
- Branding requirements: Obligations to display manufacturer logos and branding in ways that benefit the manufacturer's market position
Every one of those restrictions exists to serve the manufacturer. None of them exist to serve the patient. And when Inogen showed us that these agreements can be restructured overnight, with an entire dealer network eliminated to benefit a manufacturer-owned retailer, it confirmed what we had suspected for years: the authorized reseller model serves manufacturers first, patients last.
So we removed every remaining agreement. All of them. For every brand. Not as a reaction, but as a strategic decision to put Main Clinic Supply in a position where no manufacturer can ever dictate our recommendations, our pricing, or our loyalty again.
What Total Independence Gives You
When you call Main Clinic Supply at 1-800-775-0942, the oxygen specialist on the phone has no manufacturer agreement influencing the conversation. They have exactly one priority: finding the right device for your condition and your lifestyle.
They will ask about your prescription level, your daily routine, your travel plans, your noise sensitivity, and your budget. The recommendation comes from your answers, not from any manufacturer's sales targets.
Sometimes the right device is an Inogen Rove 6. Sometimes it is a GCE Zen-O lite. Sometimes the best fit is a device you have never seen on television because the manufacturer does not spend millions on TV advertising. You will hear about all of them from us, because no manufacturer agreement is telling us what to recommend, what to say, or what to leave out.
The MCS Warranty: Beyond Factory Coverage
Every new portable oxygen concentrator purchased from Main Clinic Supply ships with the full manufacturer warranty, regardless of brand. We advocate on your behalf to ensure that factory warranty is upheld. If you have a warranty issue, you call us, and we handle it. You do not navigate the manufacturer's claims process alone.
But the factory warranty is just the starting point.
The MCS Gold-Standard Warranty
Main Clinic Supply offers its own warranty coverage that goes significantly beyond what any manufacturer provides. This is not a replacement for the factory warranty. It is an additional layer of protection built by a company that has spent 14 years understanding exactly how portable oxygen concentrators fail in real life and what patients actually need when they do.
Accidental Drop Protection
This is the coverage that separates Main Clinic Supply from every other dealer in the industry.
Portable oxygen concentrators go everywhere with you. They travel in cars, on airplanes, through airports, and around your home. They get bumped, jostled, and occasionally dropped. It happens. And when it does, the factory warranty does not cover it.
No manufacturer warranty in the portable oxygen concentrator industry covers accidental drops or falls. Not Inogen. Not GCE. Not CAIRE. Not any of them. Zero.
The MCS gold-standard warranty includes drop coverage. If your concentrator is damaged by an accidental drop, you are covered. This is the kind of real-world protection that only comes from a company that has spent 14 years listening to what actually goes wrong with these devices in patients' daily lives, and then building a warranty that actually addresses it.
Factory Warranty Advocacy
Even for standard factory warranty claims, MCS provides something most dealers do not: active advocacy. When you purchase from Main Clinic Supply and have a warranty issue, our team works directly with the manufacturer on your behalf. We know the warranty terms for every brand we sell. We know the claims process. We know how to document the issue so it gets resolved efficiently. You are not left to figure it out alone.
This is another advantage of having a factory-certified repair center on site. When we submit a warranty claim, it comes with a professional diagnosis from certified technicians who speak the manufacturer's technical language. That carries more weight than a customer describing a problem over the phone.
How We Compare
The table below compares the service and warranty experience at Main Clinic Supply versus what a typical authorized dealer or manufacturer-direct purchase provides. The portable oxygen concentrator itself is the same device regardless of where you buy it. The difference is what happens after you buy it, who is guiding your decision, and how well you are protected.
| Coverage Area | Main Clinic Supply (Independent) | Typical Authorized Dealer |
|---|---|---|
| Manufacturer reseller agreements | None. MCS holds no authorized reseller agreement with any manufacturer | Bound by manufacturer contract with restrictions |
| Corporate ownership | Family-owned. No manufacturer or corporate parent. Our only stakeholder is the patient | May be owned by a manufacturer's parent company. Oxygen Concentrator Store is operated by AMSR, LLC, a subsidiary of Niterra Co., Ltd., the same corporation that owns CAIRE Inc. |
| Factory repair certifications | Active certifications for all leading POC brands | Typically certified on one brand only |
| Factory warranty | Full manufacturer warranty on every new unit | Full manufacturer warranty |
| Accidental drop coverage | Yes. Included in MCS gold-standard warranty | Not covered by any manufacturer warranty |
| Warranty advocacy | MCS handles manufacturer claims on your behalf with certified technician documentation | Customer often navigates manufacturer process directly |
| In-house repair center | Yes. Rochester, MN. Factory-certified technicians, 14+ years | Varies. Many ship units to manufacturer for repair |
| Brands available | Inogen, GCE, CAIRE, O2 Concepts, Rhythm Healthcare, others | Typically one primary brand, especially when the retailer is owned by a manufacturer |
| Recommendation basis | Patient's prescription, lifestyle, budget. No manufacturer influence | May be influenced by manufacturer contract terms or corporate ownership |
| Verified customer reviews | 10,000+ verified five-star reviews (Shopper Approved) | Varies by dealer |
| Years in business | 14+ years (founded 2012, Rochester, MN) | Varies by dealer |
Swipe left to see more columns
Frequently Asked Questions
Is Main Clinic Supply an authorized Inogen dealer?
No. Inogen eliminated its independent dealer network in 2025 and granted exclusive reseller rights to Oxygen Concentrator Store, a retailer owned by the same parent corporation as CAIRE Inc. Main Clinic Supply was among the independent dealers Inogen dropped. After that, MCS made the decision to drop every remaining manufacturer reseller agreement to achieve total independence. MCS holds no authorized reseller agreement with any manufacturer, and our only loyalty is to the patient. MCS remains factory-certified to repair all leading portable oxygen concentrator brands.
Why did Inogen drop its independent dealers?
Inogen restructured its reseller program and established an exclusive retail relationship with Oxygen Concentrator Store. The practical effect is that Inogen's retail distribution is now controlled by a single entity that is owned by the same parent corporation as CAIRE, another major POC manufacturer. Inogen has not publicly detailed its reasons for eliminating its independent dealer network. What we can tell you is the result: patients lost access to a network of independent dealers who offered competitive pricing and unbiased, multi-brand recommendations.
Is Oxygen Concentrator Store owned by a manufacturer?
Yes. Oxygen Concentrator Store is operated by AMSR, LLC. AMSR, LLC is a subsidiary of Niterra Co., Ltd., a publicly traded Japanese conglomerate (Tokyo Stock Exchange). Niterra also owns CAIRE Inc., one of the largest portable oxygen concentrator manufacturers in the world. This means Oxygen Concentrator Store and CAIRE share the same corporate parent. This is documented in Niterra's own consolidated financial statements, where both CAIRE Inc. and AMSR, LLC appear as acquired subsidiaries.
When a retailer is owned by the same parent corporation as a manufacturer, and that retailer is also the exclusive authorized reseller for a competing manufacturer like Inogen, two major manufacturers are effectively linked through one corporate-owned retail channel. Main Clinic Supply is family-owned. No manufacturer, no corporate conglomerate, and no parent company has any ownership stake in our business. When our oxygen specialists recommend a device, the only thing influencing that recommendation is your prescription, your lifestyle, and your budget.
Will Inogen honor my warranty if I buy from Main Clinic Supply?
Yes. Manufacturer warranties are attached to the product, not the dealer. This is a standard practice across the medical device industry. Every new portable oxygen concentrator purchased from Main Clinic Supply ships with the full factory warranty from the manufacturer, whether that is Inogen, GCE, CAIRE, or any other brand we carry. If anyone tells you otherwise, they are providing inaccurate information. Beyond the factory warranty, MCS provides active warranty advocacy, meaning our team handles manufacturer claims on your behalf using documentation from our factory-certified technicians. And the MCS gold-standard warranty adds coverage that no factory warranty offers, including accidental drop protection.
Is it safe to buy a portable oxygen concentrator from a non-authorized dealer?
Yes, provided the dealer sells genuine, new, factory-sealed devices from established manufacturers and has the technical expertise to support them. Main Clinic Supply meets every one of those criteria and then some. Every unit we sell is new, genuine, and factory-sealed. Our technicians hold active factory repair certifications for all leading brands. We have been in business for 14+ years, we hold an A+ BBB rating, and we have 10,000+ verified five-star customer reviews. The word "authorized" in "authorized dealer" refers to a reseller sales agreement. It does not mean the dealer is more qualified, more experienced, or better equipped to support you. In our case, independence made us better equipped to support you, because it removed the restrictions that were limiting what we could recommend and how we could price it.
Is Main Clinic Supply certified to repair portable oxygen concentrators?
Yes. Main Clinic Supply holds active factory repair certifications for all leading portable oxygen concentrator manufacturers where certification exists. The MCS service center in Rochester, Minnesota is staffed by factory-trained technicians with 14+ years of hands-on experience repairing thousands of devices across Inogen, GCE, CAIRE, O2 Concepts, Rhythm Healthcare, and other platforms.
Does the manufacturer warranty still apply if I buy from Main Clinic Supply?
Yes. Manufacturer warranties are attached to the product, not the dealer. Every new portable oxygen concentrator purchased from Main Clinic Supply ships with the full factory warranty. Beyond that, MCS offers its own gold-standard warranty coverage that exceeds factory terms, including accidental drop protection, which no manufacturer warranty in the industry covers.
What is included in the MCS gold-standard warranty?
The MCS gold-standard warranty goes significantly beyond any factory warranty. It includes full manufacturer warranty advocacy (MCS ensures the factory warranty is upheld on your behalf), extended service coverage through the MCS Rochester service center, and accidental drop protection that covers damage from drops and falls. Drop coverage is unheard of in any factory warranty in the portable oxygen concentrator industry.
Why did Main Clinic Supply drop all authorized reseller agreements?
The catalyst was Inogen's decision to eliminate its independent dealer network and go exclusive with a retailer owned by the same corporation that owns CAIRE, another major POC manufacturer. That move showed us exactly where the industry was heading: toward consolidation that serves manufacturers at the expense of patient choice and fair pricing. Rather than remain in reseller agreements that could be restructured overnight to serve a manufacturer's interests, MCS dropped every remaining agreement with every manufacturer. We are now 100% independent. No manufacturer controls our recommendations, our pricing, or our communication with patients.
What does factory-certified repair mean?
Factory-certified repair means that Main Clinic Supply technicians have completed manufacturer training programs and hold active certifications to diagnose, repair, and service portable oxygen concentrators. This includes sieve bed replacement, battery diagnostics, firmware configuration, and full preventative maintenance. MCS holds active repair certifications for all leading POC brands where certification exists, giving its technicians cross-platform expertise that single-brand shops do not have.
Can I still buy Inogen products from Main Clinic Supply?
Yes. Main Clinic Supply carries genuine, new, factory-sealed Inogen Rove 6, Rove 4, and related accessories. MCS also carries portable oxygen concentrators from GCE, CAIRE, O2 Concepts, Rhythm Healthcare, and other manufacturers. Because MCS holds no authorized reseller agreement with any manufacturer, its oxygen specialists are free to recommend the best device for each patient's specific needs without manufacturer influence.
Why is Main Clinic Supply cheaper than buying direct from Inogen?
Inogen spent $29.1 million on advertising in 2025 alone. That cost does not disappear. It is built into the price of every unit Inogen sells, whether you buy from Inogen directly or from an authorized dealer bound by Inogen's pricing restrictions. Main Clinic Supply does not carry a $29.1 million advertising budget. We do not run national television campaigns. We built our reputation over 14 years through 10,000+ verified five-star reviews from real patients and their families. Lower overhead means lower prices for you, without any compromise on the product itself. You receive the same genuine, new, factory-sealed device with the same full manufacturer warranty.
Why does Inogen spend over $29 million a year on TV advertising?
Inogen's business model relies heavily on direct-to-consumer television advertising to generate phone calls from patients who need supplemental oxygen. In 2025, Inogen spent $29.1 million on advertising. That budget creates powerful brand recognition. When patients search for a portable oxygen concentrator, Inogen is often the only name they know, not because Inogen makes the best device, but because Inogen spends the most on advertising. That $29.1 million is a real cost, and it is reflected in the price patients pay for Inogen products. Other manufacturers, including those whose devices match or exceed Inogen's specifications in areas like display technology, battery efficiency, noise levels, and user interface, spend a fraction of that on advertising. Main Clinic Supply exists to make sure you know about all of your options, not just the ones with the biggest TV budget.
Does Main Clinic Supply sell used or refurbished units as new?
No. Every new portable oxygen concentrator sold by Main Clinic Supply is genuine, new, and factory-sealed. We do offer certified pre-owned devices as a separate, clearly labeled category for patients who need a more affordable option. Those units are fully inspected, tested, and serviced by our factory-certified technicians before they are offered for sale, and they are always identified as pre-owned. We would never represent a used or refurbished device as new. Our 14-year reputation and 10,000+ verified five-star reviews are built on doing the right thing for every patient, every time.
Can Main Clinic Supply service my concentrator if I bought it somewhere else?
Yes. Main Clinic Supply services portable oxygen concentrators regardless of where you purchased them. Our factory-certified technicians in Rochester, Minnesota repair and maintain devices across all leading brands, including Inogen, GCE, CAIRE, O2 Concepts, and Rhythm Healthcare. You do not need to have purchased from MCS to receive service from us. If your current dealer cannot provide timely repair, or if you are tired of shipping your device back to the manufacturer and waiting weeks, call us at 1-800-775-0942. We can often turn repairs around faster because we do the work in-house.
Can I trade in my old concentrator at Main Clinic Supply?
Yes. Main Clinic Supply accepts trade-ins on portable oxygen concentrators. If you have an older device, whether it is an Inogen G3, G4, G5, or a unit from another manufacturer, our team can evaluate it and apply a trade-in credit toward a new device. Trade-in value depends on the model, condition, and age of your current unit. Call 1-800-775-0942 to speak with an oxygen specialist about your specific situation. Many patients are surprised at the value still in their older devices, and a trade-in can make upgrading to a current-generation concentrator significantly more affordable.
Were You Told Something About Main Clinic Supply? Warranty? Not Allowed to Sell Inogen? They Can't Service Inogen Machines? Anything They Told You That Was Negative About Main Clinic Supply?
Some competing dealers go out of their way to discourage patients from purchasing through Main Clinic Supply. The most common false claim is that your warranty will not be valid if you buy from us. That is not true. Every new device we sell ships with the full manufacturer warranty, and our MCS gold-standard warranty adds protection that no factory warranty offers.
But warranty misinformation is not the only thing we hear about. If a competitor, sales representative, or anyone else told you something about Main Clinic Supply that made you hesitate, whether it was about warranties, authorization, product quality, service, or anything else, we want to know. Even if you are not sure whether what you were told is true or false, use the form below. We will get back to you with the facts.
What Customers Say About Main Clinic Supply
Verified store reviews from Shopper Approved.
Disclaimer: This information is for educational purposes only. Main Clinic Supply is an independent portable oxygen concentrator specialist that holds no authorized reseller agreement with any manufacturer. Product warranties are governed by manufacturer terms and the MCS service agreement; contact Main Clinic Supply at 1-800-775-0942 for complete warranty details. All manufacturer names and trademarks referenced on this page are the property of their respective owners. Main Clinic Supply is not affiliated with, endorsed by, or authorized as a reseller by any manufacturer mentioned. Corporate ownership information regarding Niterra Co., Ltd., CAIRE Inc., and AMSR, LLC is sourced from Niterra's publicly filed consolidated financial statements. Inogen's exclusive reseller arrangement with Oxygen Concentrator Store is publicly stated by Oxygen Concentrator Store on its website. For medical advice, consult your physician. For Medicare coverage questions, contact your plan administrator.