Tcab

Tcab speeds signup and booking with nickname-based use and ZKP Framework® secure information isolation

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Signup centered on email and nickname, Apple/Google SSO, and ZKP Framework® isolation of identity documents (escrow-like custody). Booking and payment canonical: https://www.tcab.com/. 14 languages and AI driving-eligibility checks for about 200 countries.

TANAAKK Inc. (headquarters: Marunouchi, Chiyoda-ku, Tokyo; Representative Director and President: Masayoshi Aoki; hereinafter “TANAAKK”) and mobility operator TANAAKK EVGRID Inc. (headquarters: Marunouchi, Chiyoda-ku, Tokyo; Representative Director and President: Kensuke Suzuki; hereinafter “TANAAKK EVGRID”) announce that Tcab — car-share and car-rental in Fukuoka and Okinawa — consolidates booking, inventory, pricing, payment, and education content on the canonical site https://www.tcab.com/, so membership signup through reservation completion stays on one host.

Customers sign up at https://www.tcab.com/ and complete station selection, availability, insurance/options, driver checks, and payment via Tcab Explorer (Web / iOS / Android). In principle, signup only requires an email address and a nickname (handle). Birthday, gender, legal name, and address are not entered as free text. Identity is primarily assured through Apple / Google SSO, and field operations run on nicknames. Beyond a fully paperless flow, secure information isolation (escrow-like custody) under ZKP Framework® (Zero-Knowledge Policy Framework) lets rentals proceed without exposing identity documents or payment data to field staff.

Start booking or signup

When linking from media or partners, please use https://www.tcab.com/. The public canonical host is www.tcab.com.

Background

Regional travel often needs last-mile cars beyond trains, buses, and taxis. Counter rental still faces multilingual support, privacy compliance, hours, full-tank returns, and staffing. Collecting and showing unnecessary personal data also raises signup friction, cognitive load, and leak risk.

Tcab completes station choice through payment and identity checks online. Ordinary driving fuel is included in the base fare (no full-tank return required), with 24-hour pickup and return when inventory allows (see live booking screens and terms).

ZKP Framework® secure information isolation (escrow-like custody)

Tcab applies TANAAKK’s ZKP Framework® to signup, identity checks, and field ops. Zero-Knowledge Proof means proving a statement without revealing other information. ZKP Framework® extends that idea to rental operations: pass only proofs the business needs; do not hold, show, or use other personal data — maximizing signup, bookings, authentications, and inventory turns.

“Escrow-like custody” here is not classic three-party payment escrow. It means placing identity documents and payment data in isolated custody and releasing only rental-eligibility proofs to the field, separating “identity can be verified” from “staff see a person’s full profile.”

Nickname-centered use

How information is isolated

Field teams need rental eligibility proofs — Account authenticated / Driving eligibility verified / Payment authorized / Rental permitted = TRUE — not life-history attributes. Zero-knowledge is a growth algorithm that lowers signup friction and raises authentication completion and inventory turns.

Current service specs

Booking flow

  1. Choose a station on the Tspot list
  2. Pick times, vehicle size, and options on booking
  3. Sign in (email + nickname / SSO), add payment, complete driver checks

Live inventory and prices on the booking screen are authoritative. Cancellation rules: cancel policy.

Tspot stations

Multilingual and AI-agent guidance

UI and guides are available in 14 languages. Conversational AI agents such as ChatGPT, Gemini, Claude, and Cursor can use llms.txt to guide booking (not an official product partnership). Inventory: availability matrix; completion stays in a customer session on www.tcab.com.

Companies

TANAAKK Inc.

Digital vertically integrated GAAS software platform provider for Tcab IP, software, algorithms, and databases (payments, eKYC, booking, inventory exclusivity, on-demand dispatch, ZKP Framework® design). ISO 9001 and ISO 27001. https://www.tanaakk.com/

TANAAKK EVGRID Inc.

Licensed motor vehicle rental operator with branches in Fukuoka and Okinawa. Invoice registration T3180301037480. https://rent.tanaakk.com/

Contact

TANAAKK Inc. / TANAAKK EVGRID Inc. PR: Mukai
E-mail: info@tanaakk.com
Tel: +81-3-6257-5600
Site: https://www.tcab.com/

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