Would it be ok if the journalist buys the stock 10 seconds after the publication / blog post goes live? If not, how long should he wait? What about somebody wh

Would it be ok if the journalist buys the stock 10 seconds after the publication / blog post goes live? If not, how long should he wait? What about somebody who has insider information, publishes it on his personal blog (which is read by very few people), wait a day, then buys some stock? It's an interesting topic, I'm going to research it a little more, and look into our european laws :)