A patent that Mazda filed with the US Patent and Trademark Office, published on July 2, 2026, has set off a familiar round of sports-car speculation. The drawings show a small, low convertible with doors that swing outward and upward, and the coverage that followed reached the obvious conclusion: the next Mazda sports car might get butterfly doors.
Autoblog framed it as a possible feature of the next MX-5 Miata.
Those doors are real, and they are in the filing. What gets lost is that they are almost a footnote to what the patent is about, and the car in the drawings does not match the concept everyone keeps pointing to. Read the document rather than the headline and a more grounded story appears.
Key Takeaways
- The patent is US 2026/0184373 A1, “Body Structure for Vehicle,” assigned to Mazda Motor Corporation, filed December 18, 2025, and published July 2, 2026.
- Its main subject is a frontal-crash load path, not the doors. The abstract describes how a front frame channels collision energy toward the rear of the car through the side sills.
- The doors appear as a consequence of the structure. The filing describes “a flip-up side door” that moves “outward and upward like a scissor door or a butterfly door.”
- The drawings show a front-engine, rear-drive convertible with a longitudinal four-cylinder, which points away from the rotary Iconic SP concept and toward something Miata-shaped.
- A patent is not a product. Automakers file body-structure patents routinely, and nothing here confirms the mechanism reaches any showroom.
- The next MX-5 is expected around 2027 with a naturally aspirated 2.5-liter SkyActiv-Z engine and a sub-1,000-kilogram weight target.
What the Patent Claims
The document is titled “Body Structure for Vehicle,” and the title is the tell. Its abstract opens on crash engineering, not styling.
“A frontal collision load is efficiently transmitted from a front frame to the rear of a vehicle,” it reads, before describing side sills that overlap the lower end of each hinge pillar in an inward-displaced shape, and cast front-frame sections that enlarge toward the rear where they meet the dash panel. This is a filing about where impact energy goes.
The doors enter the picture because of that geometry. To tie the front structure into the shock towers the way Mazda wants, the outer hinge pillar is raked, “inclined downward to the front,” with the upper and lower hinge points arranged so the door hinges themselves angle downward toward the rear.
A door hung on hinges set at that angle does not swing out sideways. It lifts.
The patent spells out the result in plain language: “a flip-up side door, in which a door rear portion is displaced outward and upward like a scissor door or a butterfly door when the door is opened.”
So the exotic doors are downstream of a crash-structure decision. Mazda did not set out to patent theatrical doors and hang a chassis behind them. It patented a load path, and the load path happens to require a door that opens up rather than out.
That is a different story from the one the headlines told, and it is the more honest one.
One detail worth attributing carefully: the widely repeated “45-degree” hinge angle comes from CarBuzz, which discovered and analyzed the filing and read that figure off the patent drawing. The patent text retrieved for this piece does not state a specific angle. Treat the number as an informed estimate from the drawing, not a specification.
The Car in the Drawings Isn’t the Rotary Iconic SP
Most of the coverage pairs this patent with the Mazda Iconic SP, the low red concept the company showed at the 2023 Japan Mobility Show. The visual match is tempting, and CarBuzz was candid that it created that association by overlaying the patent drawing on the concept. The powertrains, though, do not line up.
By contrast, the Iconic SP is a rotary car. Mazda described it as a two-rotor rotary-EV, with the rotary engine acting as a generator for an electric drive system, making 370 PS at a 1,450-kilogram curb weight and a near 50:50 balance.
The patent drawings show a different picture: a longitudinal, front-mounted four-cylinder engine, a visible transmission tunnel, and a front-engine, rear-drive layout. A four-cylinder in the nose is the signature of a Miata, not of the rotary halo car people keep invoking.
That leaves the honest answer as an open one. The filing could describe architecture for the next MX-5. It could describe a separate front-engine sports car. It could, like most patents, describe an idea Mazda wants to own without building.
What it is not is proof of butterfly doors on the Iconic SP. The engine under the hood of the patent car is the wrong shape for that concept.
Why Butterfly Doors and the Miata Sit Uneasily Together
Set aside which car the patent describes and a second tension appears. Vertical-opening doors run against everything the MX-5 has stood for. The Miata’s whole argument is low cost, low weight, and mechanical simplicity, the same qualities Mazda’s engineers have been fighting to protect as the next car adds light electrification.
Scissor and butterfly hinges add mass, cost, and complexity. They tend to live on supercars and show stands, not on attainable roadsters.
A halo car can carry that hardware. An RX-7 successor built to justify a high price and a dramatic silhouette has room in its budget for doors that lift. A roadster a young enthusiast can nearly afford does not.
If the patented structure ever reaches production, the doors are far more plausible on a range-topping sports car than on an MX-5 that has to stay affordable to make sense.
None of that rules the Miata out. It means the flashy detail and the practical car pull in opposite directions, and that friction is the reason to read the filing as engineering groundwork rather than a preview of the next Miata’s party trick.
Where the Next MX-5 Stands
What Mazda has committed to for its next sports car lives in the powertrain, not the doors.
The fifth-generation MX-5, expected around 2027, is set to use a naturally aspirated 2.5-liter SkyActiv-Z four-cylinder running near 16:1 compression, paired with light electrification most likely built around a 48-volt system. Design chief Masashi Nakayama has said the car targets under one tonne in weight and under four metres in length, calling lightness both the most important and the second most important priority.
That program is where the real news about the next Miata sits, and it is covered in depth in our look at why a sub-1,000-kilogram hybrid Miata still works. A patent drawing of lifting doors is a fun artifact. The engine and the weight target are the decisions that will define whether the next MX-5 is still a Miata.
Keep the patents straight. Mazda has filed a cluster of sports-car-related patents over the past two years, and coverage tends to blur them together. The butterfly-door filing published July 2, 2026, is separate from an earlier November 2024 patent about battery placement and from a separate electric sports-car chassis patent that surfaced in 2025. Only the July 2026 document describes the flip-up doors. A date attached to one is not a date attached to the others.
What to Take From It
A patent publication is a look at what a company is willing to protect, not a spec sheet for what it will sell. This one shows Mazda working on a front-engine, rear-drive sports-car structure whose crash geometry produces doors that open upward.
That is worth noting on its own. Mazda is still investing in combustion sports cars while much of the industry moves elsewhere.
The leap from there to “the next Miata has butterfly doors” skips several steps the document does not support. The car in the drawings might be the MX-5, might be a pricier stablemate, and might be neither.
The doors are a side effect of a load path. And the whole thing remains ink on a patent, which is a long way from a hinge you can open in a showroom.
Bottom Line
Mazda’s new patent is being read as a butterfly-door reveal, but the filing itself is a crash-structure document, and the lifting doors fall out of its hinge-pillar geometry rather than driving the design. The four-cylinder, rear-drive convertible in the drawings does not match the rotary Iconic SP the coverage keeps invoking, and vertical doors sit awkwardly on a car whose appeal rests on staying light and affordable. Read it as evidence that Mazda is still committed to combustion sports cars, and wait for the powertrain and the weight before deciding what the next MX-5 becomes.
Frequently Asked Questions
Did Mazda confirm butterfly doors for the next MX-5?
No. Mazda filed a body-structure patent, published July 2, 2026, that describes a flip-up door opening “like a scissor door or a butterfly door.” A patent is not a production commitment, and the filing does not name the MX-5 or any specific model.
What is the patent number?
It is US 2026/0184373 A1, titled “Body Structure for Vehicle,” assigned to Mazda Motor Corporation. It was filed with the US Patent and Trademark Office on December 18, 2025, and published on July 2, 2026.
Is the patent about the doors?
Not primarily. The abstract and main claims describe a frontal-crash load path that channels impact energy from the front frame through the side sills to the rear of the car. The upward-opening doors are a consequence of the raked hinge-pillar geometry the crash structure requires.
Is this the Mazda Iconic SP?
The drawings do not match it. The Iconic SP concept from 2023 uses a two-rotor rotary-EV powertrain, while the patent shows a longitudinal front-mounted four-cylinder with a transmission tunnel and rear-wheel drive. That layout is closer to the MX-5 than to the rotary concept.
What is the difference between scissor doors and butterfly doors?
Scissor doors hinge at the front and rotate straight up, staying close to the body. Butterfly doors hinge at an angle and swing outward as they lift, giving easier cabin access. Mazda’s patent references both as examples of the flip-up motion its hinge geometry produces.
When is the next Mazda MX-5 coming?
The fifth-generation MX-5 is expected around 2027, though Mazda has not set an official date. It is expected to use a naturally aspirated 2.5-liter SkyActiv-Z engine with light electrification and a weight target under 1,000 kilograms.
Who discovered the patent?
CarBuzz reported discovering and analyzing the filing, including an overlay comparison with the Iconic SP concept and an estimate of the hinge angle from the drawing. Autoblog and other outlets aggregated that reporting, which is how the story reached wider coverage.
Does a patent mean the feature is coming?
Not on its own. Automakers file thousands of patents to protect ideas, many of which never reach production. This filing shows Mazda developing a front-engine, rear-drive sports-car structure, but it does not confirm the doors, the model, or a timeline.
Michael Kahn
Michael Kahn is the writer, photographer, and publisher behind The Weekly Driver. He cares about how cars drive and what they're like to own. He covers automobile industry news, car shows and events, and new car reviews. The reviews come from behind the wheel: day trips that favor back routes, treating a good meal as half the reason to go. He directs and produces the visual media, matching each car to a setting and mood that fit it. When he's not reviewing new cars, Michael races paddleboards, camels, and ostriches, along with the occasional exotic car on the racetrack, and has driven in every state and country visited.
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