Apple Inc.

Jeremy M Stober

Augustin J Farrugia

Mathieu Ciet

Gianpaolo Fasoli

Benoit Chevallier-Mames

Julien Lerouge

Eric Daniel Friedman

Ritwik K Kumar

Lucas Olen Winstrom

Amol V Pattekar

Systems and methods are described for rate-limiting a message-sending client interacting with a message service based on dynamically calculated risk assessments of the probability that the client is, or is not, a sender of a spam messages. The message service sends a proof of work problem to a sending client device with a difficulty level that is related to a risk assessment that the client is a sender of spam messages. The message system limits the rate at which a known or suspected spammer can send messages by giving the known or suspected spammer client harder proof of work problems to solve, while minimizing the burden on normal users of the message system by given them easier proof of work problems to solve that can typically be solved by the client within the time that it takes to type a message.

Method for rate-limiting interactions based on dynamically calculated values by supplying problems of varying difficulty to be solved

Growing community of inventors

Austin, TX, United States of America

Jeremy M Stober