I was going through my passport and noticed that some of the entry and exit stamps are not neatly placed. This made me wonder, are there any rules or regulations saying where and how stamps are placed in a passport? Does it fall on the immigration(?) officer to check if there is room on the passport for a entry and leave stamp? Wouldn't that leave room for human error?
There is no universal rule on stamping visas, entry or exit stamps in passports other than, they are not supposed to be stamped on Amendment / Endorsements pages in the back of passport (but if there is no other space...)
In the good old days, passport pages were divided into quarters and countries used two quarters, left for the entry, right for the exit stamps. I think it was more just customary rather than mandatory.
Today immigration stamps come in a myriad of sizes and shapes, and many immigration officers can't be bothered to make the stamping look neat. Most will try to put the entry and exit stamps on the same or facing pages. I have pages with 6 to 8 stamps on them.
Some countries do have rules that your passport needs to have XX completely blank pages and you will not be granted entry (nor be allowed to board the plane to those countries) without the blank pages. Others will simply stamp in any blank spot big enough for their stamp.
Generally, they stamp wherever they feel like.
I have about fourty US entry stamps on one page (the one that opens up when you just shake the passport). Of course, none of them is readable anymore, which doesn't keep the next officer from stamping right on top of them.
I'd say most western countries pay little attention and stamping passports has mostly become a routine and tradition and not much more. Of course, some countries are rather anal about it and match each entry to the exit stamp before they let you go, and others even look at other countries stamps, and ask you why you were in X nine years ago and such.
But all those guys know that their colleagues from other countries don't care where they stamp, so they don't expect any order or sense in the positioning or distribution.