StarkWare launches OffMarket for private trading on Polymarket

Polymarket traders have long operated in public. Every bet, balance, and position sits on-chain for anyone curious enough to look.

StarkWare now wants to change that. The company has opened OffMarket to the public, a platform that lets Polymarket users trade without publicly linking their positions to their accounts.

How OffMarket works

OffMarket, which lives at offmarket.cx, runs on a privacy layer built on Starknet. That layer uses zero-knowledge proofs to obscure user balances and trading activity.

In OffMarket’s case, the proofs shield activity on the Polygon network. Polymarket’s markets keep functioning normally, while the link between a trade and the person behind it gets blurred.

Traders deposit USDC on Polygon and can start trading without ever creating a Polymarket account.

OffMarket handles the wallet side itself. It manages derived wallets on behalf of users, which separates each trade from a trader’s primary identity on-chain.

OffMarket does not try to build a rival market from scratch. It plugs into Polymarket’s existing order books, odds, and liquidity, so private traders are not stuck in a smaller, thinner pool.

StarkWare frames OffMarket as something like a VPN for Polymarket users: same internet, less visibility into who is browsing.

A slow walk to public launch

The rollout came in stages across much of 2026. It started with a private alpha in July 2026. Invite-only access followed in August. Mainnet privacy trading arrived in September. Full public availability landed around mid-October 2026, with the public launch on or around October 14.

The project carries an “Official @Polymarket Builder” status. Even so, OffMarket operates independently of Polymarket itself.

Why on-chain transparency became a problem

Public blockchains were built around radical transparency. Every wallet’s activity is visible on-chain, and for many use cases, that openness is a feature.

For traders, it can be a liability. A visible wallet means visible strategy, visible position sizes, and visible conviction. Large bettors can be tracked, copied, or front-run, and their activity can become a story in itself.

What this means for Polymarket, Starknet, and traders

For StarkWare, OffMarket is as much a showcase as a product. The company promotes it as a practical demonstration of what Starknet’s privacy capabilities can actually do.

StarkWare has emphasized that the launch is significant for both DeFi and prediction markets. Its core argument is that privacy tools can upgrade existing trading ecosystems without forcing users onto entirely separate networks.

Rather than asking traders to leave Polymarket, OffMarket wraps privacy around the market they already use.