Before last night's win, Leeds manager Marcelo Bielsa accepted responsibility for his club spying on Derby's training session on Thursday, saying that it was his idea.
Lampard said: "I don't think we need to [make a complaint] because he has admitted it. It's up to the league to see how they deal with it. Obviously it's not just Derby County. We had someone the day before we lost 4-1 against them.
"Now, Leeds can beat you 4-1 they are a fantastic team but we had someone in the bushes that day so twice this season now. The man was asked to leave but it wasn't followed up like it was this time."
Asked about Bielsa taking responsibility, Lampard said: "Well that's good, I spoke to him yesterday afternoon myself and he did the same to me so I'm pleased he's done it again and said that. I think it makes it easier to deal with because at least, on a sportsmans' level, it's bad in my opinion.
"If we are going to talk about culturally I did it somewhere else and it was fine then that doesn't work for me because I don't believe that it is fine on that level. It has disrupted our build-up for this game.
"The fortunate thing is that it has disrupted us without really doing anything. People will stand here and say I'm trying to make excuses before the game, I will speak like this after the game as well, win, lose or draw because of what's happened."