To provide validation information to web publishers indicative of the presence of operational malicious software protection systems on user computing devices, an evaluation system resident on a web publisher server can cause web content, including validation request data, to be transmitted from the publisher server to a computing device. A submission system resident on the computing device can analyze the web content for the validation request data, and can cause the validation information to be transmitted from the computing device to the evaluation system based on the analysis. Upon receiving the validation information, the evaluation system can analyze it to determine the likelihood that content delivered to the computing device will be viewed by a real user (and not by automated computer programs).