The trail of breadcrumbs pointing to the return of a proper, rally-bred hot hatchback has been an incredibly entertaining one to follow. Shortly after a certain Japanese automaker put its new racing prototype through testing, a set of highly detailed patent drawings surfaced online, fueling massive speculation among US enthusiasts about a potential street-legal production version.
According to a recent report from CarScoops, the newly uncovered patents depict a Subaru hatchback rocking a massive widebody kit, WRX-sourced headlights, a completely redesigned grille, and some very prominent aero components. If it looks familiar, it should.
It looks nearly identical to the aggressively styled Subaru Performance-B STI Concept that debuted at the 2025 Japan Mobility Show.
Concept Design Captured in Patents
A closer look at the filings reveals only minor differences from the concept car, 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.
As reported by Top Gear Philippines, which originally spotted the filing on the Japan Platform for Patent Information, the documents were submitted on September 29, 2025, exactly one month before the show car’s debut. The timing, combined with the near-perfect visual match, strongly suggests these drawings were filed to protect the design of the Subaru Performance-B STI Concept, rather than outright confirming a rumored 2027 production model.
In fact, standard automotive industry practice backs this up. A quick search of the same database shows that similar patents for the fully electric Subaru Performance-E STI Concept were filed on the very same day to prevent copyright issues ahead of their public debut.
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What About the STI Rumors?
While these specific patents likely exist for legal reasons, the timing of their discovery is exactly what has American enthusiasts paying close attention. Subaru’s HiPerfX2 hatchback, which is essentially the racing counterpart to the Performance-B STI Concept, is currently set to compete in Japan’s Super Taikyu series. There, it will double as a rolling development lab.
The race car pulls together an assortment of WRX STI sedan components, wrapped in a widebody hatchback silhouette that appears to draw heavy inspiration from the Impreza. Under the hood sits a motorsport-tuned version of the turbocharged 2.4-liter boxer engine, producing a meaty 359 hp, paired with a traditional six-speed manual gearbox and Subaru’s legendary all-wheel-drive system.
Talk of a 2027 return for a street-legal WRX STI hatchback starts to make a lot more sense when you look at the gaps currently forming in Subaru’s global lineup. The automaker has confirmed it will soon stop taking orders for the WRX sedan in Japan, along with the Levorg and Layback wagons, leaving some shoes to fill.
Another telling move is the recent removal of the STI Sport grade from the standard WRX range. For US buyers still mourning the loss of the WRX STI, this could be less about trimming options and more about clearing the stage for something much more exciting.
Whether this all points to a routine model year reshuffle or a deeper reset that finally brings the iconic STI badge back to a proper hot hatch is still an open question, but the evidence is certainly piling up.
