What will TEFCA’s financials look like in 2028? Brendan Keeler recently challenged my proposal for a patient-developer credential — he expressed concern that if patients could get a free “TEFCA Credential” that they could plug into any software of their choice… this would create an arbitrage opportunity that might drive many of TEFCA’s high-paying business-oriented participants to jump ship and leverage the patient-mediated path, asking their users to deliver the data to them. I wasn’t sure this would be such a bad thing, and I used Claude 4 + Gemini Pro 2.5 to put together a little simulation at https://lnkd.in/gfTJqbrF .

The simulation suggests if patients cover the cost of ID verification when their receive this credential, then even if 50M patients went this route and 25% of business-oriented participants dropped out of TEFCA, the remaining stakeholders would see participation fees increase by ~5%.

The analysis is quite sensitive to the marginal cost of queries, and the networks will have incentives to drive this down if they are appropriately exposed.

“I’d love feedback on what I’m getting right/wrong here (structurally and in the default parameter values)!