Pre-IPO perpetual contracts tied to Anthropic generated $643 million in trading across 12 crypto venues through Sept. 21, according to Binance Research, outpacing the $590 million recorded for all of August and exposing how a synthetic valuation market has formed without any public equity anchor.

About $80 million of Anthropic-linked open interest was outstanding at the September snapshot. On Binance alone, open interest rose 88% over 30 days to $31.2 million from $16.6 million. Binance Research measured combined open interest in Anthropic and OpenAI pre-IPO perpetuals above $160 million as of Sept. 15, up from roughly $1 million in April.

The contracts are cash-settled derivatives priced from exchange-derived mark prices. That arrangement becomes more consequential once a stock listing introduces an external reference price that could differ sharply from the implied valuation.

What changes at listing?

Binance currently derives the mark price for its ANTHROPICUSDT contract from recent trade prints, averaging them and capping how far the mark can move per second. The exchange has said it can convert the perpetual into a standard equity-linked contract once it has a stable third-party stock-price index and issues a transition notice. Conversion does not begin automatically when shares start trading; the mark price gradually shifts toward the stock-linked calculation.

If the IPO sets a public share price materially different from the implied valuation, the convergence could shift unrealized P&L, alter collateral values, and reset liquidation thresholds for traders carrying positions through the listing. Binance said the mark-price adjustment used for an earlier conversion, SpaceX in June, could take up to three hours depending on volatility and reference-price stability.

Sensitivity to IPO timing is already visible. Over a weekend when reports indicated the listing timetable could shift, Binance's ANTHROPICUSDT perpetual fell 0.89% to $2,084 from $2,103. The exchange called the muted move consistent with some delay already being priced in.

Anthropic announced a confidential draft IPO filing in June. Reports this week suggested the debut may slip beyond the November U.S. midterm elections, per Reuters.

Does demand survive after listing?

SpaceX offers the cleanest precedent. When SpaceX listed in June, Binance kept existing positions and open orders in place while transitioning its mark price toward a stock index, the exchange said in a support announcement. FalconX reported that SpaceX perpetual open interest exceeded $300 million before the IPO and peaked 11 days after the listing. Average daily perpetual volume across venues reached $2.2 billion in the following 30 days.

Binance separately said average daily SpaceX perpetual volume on its platform climbed to about $1.6 billion after conversion, from roughly $89 million before the IPO. The figures cover different venue sets but point to the same outcome: publicly traded shares did not drain demand for the crypto derivative.

What remains unclear is whether the original pre-IPO traders retained their positions, or whether higher post-listing open interest reflects new entrants arriving once price discovery improved and the contract became easier to hedge against the stock.

When does the convergence test arrive?

OpenAI offers the contrasting case. Sam Altman has said the company will not go public in 2026, leaving its pre-IPO contracts without a listed share price to force a similar reconciliation this year. That makes Anthropic the more immediate test of how far crypto markets can front-run a private-company valuation before Wall Street sets a competing price.

The next signals will come from Anthropic's IPO timetable and any Binance transition notice. After that, market participants will track the gap between the perpetual and the listed shares, the speed of convergence, and whether the open interest built before the IPO survives once synthetic pricing has to answer to a public market.