Hilchos Rechilus, chapter 2, section 3

Some say that if someone put down another person in front of three people, it is no longer rechilus to tell about it, because the news will spread anyway. This still needs all the conditions mentioned earlier in paragraph 14 of the Laws of Lashon Hara.

But you may not rely on this leniency in practice. Many Rishonim (early authorities) disagree, and forbid telling anyone if your goal is to spread the story, and certainly not the person who was spoken about.

Even if you do not mean to spread the story, you still should not repeat it, as we wrote above in the Laws of Lashon Hara, paragraph 11.