No stamps, marks or writing - a clean copy. Age-tanning is mild to moderate and uniform. To me it seems a little dark for a book of this vintage - but you may not be able to do better for this (only) edition, given the quality of paper the publisher chose. I did notice a couple of printing problems where a few pages are printed lighter/fainter than the rest. Page 82 is one of those, and there is a smudge of the ink near middle/bottom that obsures a paragraph.

Empire - a collection of loosely related stories by H. Beam Piper. These are set in his TerroHuman Future History, after the time of Space Viking.

(Introduction by John F. Carr)
The Edge of the Knife
A Slave is a Slave
Ministry of Disturbance
The Return {with John J. McGuire}
The Keeper

These originally appeared from 1957 to 1962 in Astounding (2), Analog, Amazing, and Venture.