Does a complimentary textbook have the same info or a normal textbook?

I received a textbook for school that i ordered over amazon.com and upon opening it i discovered that on the cover of the book it says complimentary. Is the text in this book the same as in the normal textbooks? Is anything different, or is this just a free copy from the publisher?Does a complimentary textbook have the same info or a normal textbook?
Complimentary textbooks are usually copies of the book that have been distributed by publishers to teachers. These editions are provided as either incentives for educational institutions to use the textbook or can be provided if a teacher elects to use a textbook for their course as a "desk copy" for the teacher's reference. The complimentary textbooks should be exactly the same as the standard edition and it is also perfectly legal to sell these back to any company to put them into circulation. I would encourage you to notify the vendor, however, in the event that you begin using the textbook and it has some inconsistencies, as with any textbook.