2019-04-28, 19:50 (This post was last modified: 2019-04-28, 19:50 by pkscout.)
Assuming you're talking about a TV episode or movie being marked as watched (i.e. the little check mark that shows with the default skin), you can use an advanced setting to tell Kodi to only mark it as watched after more than 100% of the recording is watched. Basically like this: