Green SM's Hong Kong float prices a captive, not a champion

Hong Kong has a novel listing in the pipeline, and it is not a Chinese tech giant. Green and Smart Mobility (GSM), the Vietnamese electric-taxi operator known at home as Xanh SM, plans an initial public offering in the city that would be the first by any Vietnamese company on the exchange. To most investors the name means nothing; to Vietnam it is a fleet of green cabs that has stormed the ride-hailing market. What is actually for sale is more interesting than the brand. GSM is a captive: virtually its entire fleet is purchased from VinFast, the loss-making electric-vehicle maker owned by the same man. The listing is a test of how much outside money will pay for that arrangement.

The man behind both firms is Pham Nhat Vuong, Vietnam's richest, who founded GSM in 2023 and owns about 95% of it. The wiring is convenient for his empire. GSM hands VinFast a guaranteed domestic buyer for its cars, and VinFast's scale in turn feeds the taxi network. The flywheel spun fast in 2025: GSM more than doubled revenue to about $661m, while VinFast delivered a record 196,919 vehicles, up 102%, on revenue of $3.6bn. Yet the glamour sits on one side of the group's books. VinFast still sells cars at a gross margin of negative 42.5%, and GSM's credit profile is rated as an aggressive borrower. Its dependence on a single supplier is not a risk the structure happens to carry; it is the structure.

That is why the asking price is in dispute. Reuters, citing people familiar with the matter, reported a valuation of $2bn to $3bn — a figure that may include debt — and fundraising of at least $200m. Vingroup, the parent, floated something grander: advisers, it said, had suggested roughly $20bn. The gap is not a rounding error. A price near $20bn would put the taxi firm on par with Grab, Southeast Asia's ride-hailing incumbent and a far bigger business, and value GSM at about thirty times its 2025 revenue. Nor is the disagreement cosmetic, because the two numbers imply opposite business cases. At the low end, a buyer underwrites a young company growing fast into a defensible niche. At the high end, the buyer pays a champion's multiple for what is, in effect, the sales arm of a loss-making carmaker.

The choice of venue says less about GSM than about where such dreams get funded. Hong Kong was the world's top IPO venue in 2025, powered by a resurgent primary market hungry for electric-vehicle and mobility stories. That is precisely the point: neither Singapore nor Nasdaq offered the depth, and VinFast's own Nasdaq listing has laboured under a thin free float that left its shares illiquid. Yet there is a catch the rally obscures. Hong Kong's primary market has performed sweetly of late, but the secondary market, where existing shares actually trade, has fallen flat. Getting money in is easy; getting out, once the champagne has been drunk, has not been.

None of this makes GSM a sham. Its revenues are real, and the taxi operation has overtaken Grab in Vietnam by at least some measurements, holding about 51.5% of the country's online ride-hailing market in the fourth quarter of 2025, though rival surveys still put Grab ahead. The question is what a purchaser is really underwriting. Buying a captive taxi fleet at a champion's multiple means paying not for independent economics but for the hope that the group's internal chemistry — a sole-supplier contract, related-party prices, an owner who controls both ends of the transaction — keeps generating value that somehow reaches minority shareholders. The past suggests the value flows the other way. GSM absorbed 72% of VinFast's sales in 2023; by the third quarter of 2025 that share had fallen to 26%. The captive is sized to serve the manufacturer, not to enrich its own owners.

For the retail investor, the deal will present a clean judgment when it arrives. At the low multiple, the captive is a real business bought cheaply, with VinFast's distress already discounted into the entry price. At the floated multiple, the buyer is volunteering to finance VinFast's expansion through the back door, at full price and with no control over the terms. The venue promises an easy way in. The economics will decide whether there is a way out.