I have a britax and I always leave it up.

In the manual for our infant seat, the handle had to be up in position A, no other position was allowed while in the car.

Thanks mandabear :) love Unico and the lost unicorn. Hard to choose one :)

Thanks for all the replies. Good to know :)

I always put mine down but that is my personal preference. If it says it's ok then I would assume its ok.

On an unrelated note..... OP i love your profile picture. Unico is the best cartoon character ever. :)

Completely depends on the car seat.

Depends on the carseat. Follow your manual. Mine said only in bottom position.

It depends on the model and manufacturer. It's listed in the manual whether or not the handle should be up or down. The carseat I had for lo, the handle had to be up while driving.

I always leave it up. I don't know, I don't see an issue with it being up

The manual for my carseat says it can be used in any position so we leave it in position a

All car seat manufactures have different stipulations if you're manual tells you that its okay you can use it that way, as its been tested that way.

Um idk i always had it down but i don't see a problem if its up