Do you have the exact same surname that your direct paternal great-great-grandfather was born with?

Probably not, it was almost certainily Slavicised.

Yes

No. My paternal grandpa was born to a muslim father and catholic mother, and they could not legally marry at that time. Because of that, my paternal grandfather was assigned his mother's surname, not one of his father.

No, not at all.
I got my mothers maiden name as my lastname.
My father has his grandmothers maiden name as his last name.
I have not the slightest idea who my direct patrilinear great grandfather even was.
So much for decades of strong Catholic traditions in Austria.:picard2:

Yes, same spelling as far as known back and this is 12 generations. This 10 x great-grandfather had my 9 x great-grandfather born in 1551 or 1552 and was buried on the 24th of October 1596.

(In the bookkeeping of the village community it is recorded that in the accounting year 1543/1544 the community had given beer for his (this 10 x great-grandfather's) and 8 other weddings in an inn and that all together it had cost 81 guilders, 2 groschen and 10 pfennigs. When these accounts were later examined by the authorities, it was decreed that no more money from the community should be spent on the inn. :p )

I do. I actually didn’t expect it, but it’s written exactly the same. When I come to my third great-grandfather, though, the caron (ˇ) disappears. Besides that, the letters are the same.

Yes i do

Back to 1066 pretty much, Anglicized from a Norman place name.

No, its original form was changed a little in the documents, during the time my paternal grandfather was young. Also, I did some research and found this surname spelled differently in some centuries old records. Its origin does intrigue me and I hope to find more about it, in the future.

I have a Surname that is a misspeling of my great-great-great-grandmother's one, the proper one was lost during the immigration process (my Y-haplogroup one).
But I have it doccumented on my grandfather's birth certificate as well in all his brothers' ones. I will change it as soon as possible.