Nudged a car no details exchanged can they still claim against me?

Today I went into the back of someone's car whilst driving. The damage is minuscule where I have a small scratch on my bumper and they looked to have a similar scratch on there's nothing major. The guy leant out of his window and asked what happened there I apologised and asked if he was okay he nodded and drove off. I was more than happy to pull over and sort our details etc or sort damages with some cash but he just drove off without any questions. His car was a 03 plate ford so I can only presume due to the low amount of contact from car to car he was not fussed about damage. He didn't even get out to look at his car. I took his reg just increase and drove home. I'm wondering that if he wants to make a claim now how will he do it and will he be able to make it look a lot worse than it actually was etc as I can only presume he would have taken my reg also. Or should I not worry about this as he drove off himself without any questions etc?

Had one of those before never heard from the guy or his insurance

He can file a claim against you, but I doubt he does.

Usually people do that if there's no damage or small damage for one of 2 reasons, they don't want their rates to go up, or they don't have insurance in the first place.

If he happen to memorize your license plate he can file a hit and run against you, but it would be your word against his, and wouldn't go anywhere because he did not file a police report.

If I were you, if you do get a call from your insurance company deny it ever happened. If his insurance company calls you, you don't have to say a word to them. You never have to talk to the other driver's insurance company and its recommended you don't in any case, whether your at fault or the other driver is.

If he took your registration number, he could pass that to his insurance company, who will then find your insurance details through the Motor Insurers Database.

If he didn't take any of your details, he has no way to identify you in a claim.

Maybe once he gets home and sees the mark on his bumper he might change his mind and by then he could have whip lash
who knows

Most likely he won't and In any case you could say the matter was solved at the roadside and therefore you are exempt as you explained to him what happened and everything's fine. I doubt he will do anything