Venice got inventors to publish secrets by paying them in monopoly

Before 1474, an inventor in Venice or anywhere else in Europe who developed a valuable new technique had essentially one option for protecting its economic value: keep it secret. A trade secret offered no legal recourse if someone else independently discovered or copied it, could leak at any moment through a disloyal apprentice or a careless slip, and typically died with the person who held it, since passing it on to others multiplied the risk of it leaking further.

That secrecy-based system was bad for inventors, who had no reliable way to monetize an innovation beyond however long they could personally keep it hidden, and bad for the wider economy, since genuinely useful techniques often vanished with their inventors instead of spreading and being built upon by others.

The Venetian Senate's 1474 Patent Statute required anyone who built a new and ingenious device in the city to formally register it with the city's General Welfare Board once it was working and could be used, fully disclosing how it worked. In exchange, the inventor received a state-enforced exclusive right to make and sell the device in Venice for up to ten years, with legal recourse against anyone who copied it during that period.

Venice paid inventors in state-enforced monopoly: full disclosure to the Welfare Board bought a ten-year exclusive right, making openness more valuable than concealment.

Secrecy offered no legal recourse if leaked or reinvented, so it was fragile protection.

The statute offered a state-enforced monopoly, strictly better than secrecy's self-administered protection.

Once disclosure paid more reliably than concealment, inventors rationally chose to register.

The state got diffusion and invention without enforcement costs, only temporary exclusivity.

To get people to reveal valuable know-how, don't compel disclosure—offer a time-limited exclusive benefit that makes secrecy the losing choice.

Full public disclosure became the financially rational choice for an inventor instead of the risky one, since the statute now offered a legally enforceable exclusivity period in exchange for revealing exactly how the invention worked, something secrecy alone could never guarantee. At least 500 patents were granted under the statute between 1474 and 1600.