- The rumored STI hatchback appeared in patent drawings in Japan.
- A closer inspection suggests it is the Performance-B STI Concept.
- Still, Subaru is rumored to be working on the return of a hot hatch.
The trail of breadcrumbs pointing to the return of a proper Subaru STI has been an entertaining one to follow. Shortly after the company put its new racing hatchback through testing, a set of patent drawings surfaced online, fueling more speculation about a potential production version.
The patents, filed at the Japan Patent Office, depict a Subaru hatchback with a wide body kit, WRX-sourced headlights, a new grille, and prominent aero components. It looks nearly identical to the Performance-B STI Concept from the 2025 Japan Mobility Show.
More: Subaru Says STI Is “Not Dead”, But Its Boxer May Be
A closer look reveals only minor differences, namely the absence of extra vents on either side of the signature hood scoop and the lack of tailpipes at the rear. The latter likely relates to the patent application itself, much like the blank wheels and simplified lighting details.
Concept Design Captured In Patents
Japan Platform for Patent Information
As reported by Top Gear Philippines, which spotted the filing on the Japan Platform for Patent Information, the documents were submitted on September 29, 2025, one month before the show car’s debut on October 30. The timing, combined with the near-perfect visual match, strongly suggest these drawings depict the Subaru Performance-B STI Concept rather than a rumored 2027 production model.
More: Subaru Showed Four New STI Models, And Not Even One’s A Real STI
A quick search of the same database shows that similar patents for the Subaru Performance-E STI Concept were filed on the very same day. They replicate the fully electric fastback’s design without any changes. This is standard practice, as automakers routinely secure design protection for both concepts cars and future production models ahead of their public debut to prevent copyright issues.
What About The Rumors?
While these patents likely exist for legal reasons, the timing of their discovery is what has enthusiasts paying attention. Subaru’s HiPerfX2 hatchback, essentially the racing counterpart to the Performance-B STI Concept, is set to compete in Japan’s Super Taikyu series, where it will double as a rolling development lab.
More: Subaru’s WRX STI Hatch Is Back On Track, Just Not On The Street
The race car pulls together an assortment of WRX STI sedan components, wrapped in a widebody hatchback silhouette that appears to draw from the Impreza. Under the hood sits a motorsport-tuned version of the turbocharged 2.4-liter boxer engine, producing 359 hp (268 kW / 364 PS), paired with a six-speed manual gearbox and an all-wheel-drive system.
Subaru Performance-B STI Concept
Talk of a 2027 return for the WRX STI hatchback starts to make more sense when you look at the gaps forming in Subaru’s current lineup. The company has confirmed it will stop taking orders for the WRX sedan in Japan, along with the Levorg and Layback wagons, leaving some notable space to fill.
Another telling move is the removal of the STI Sport grade from the WRX range, which could be less about trimming options and more about clearing the stage for something more exciting with the STI badge.
Whether this all points to a routine model year reshuffle or a deeper generational reset, one that finally brings the STI badge back to a hot hatch, is still an open question.