It is illegal to hold a passport, although the company I work for allows employees to retain them with themselves or hand-over for safe-keeping!

The majority allow the company to look after them because they cannot leave without the exit permit, what is the point is keeping the passport. I, for one, keep my passport.

I am from the UK and on page 2 - Notes, section 6 - Caution it states...

"This passport remains the property of Her Majesty's Government in the United Kingdom and may be withdrawn at any time."

Therefore the passport is not even your property, it is the property of the State of issuance of the passport.