Recently I had an existing client question some copyright policies stated on my email and invoice to him. He has never questioned the policies in the past so I was surprised to see such a reaction to it on this recent shoot. He requested clarity on the following two statements. 

1. Buyer may not resell, relicense, redistribute image(s) without express written permission from my company.
2. Image(s) may not be used as a derivative work.
To me these statements are straight forward and the reason I feel he was questioning them was because he wanted to send copies of the photos to other trades who did work in the space that I photographed for him. In other words he assumed he could pay for one admission and bring all his friends into the concert with him. This is a common problem in our industry and one that has to change through education from us as professional photographers.
The interior designer who designed the space I photographed later contacted me asking if she could manipulate the photos to post on her own social media site as she wanted the colours to match her overall theme. I explained to her in a nice way that she doesn’t own a license to possess the images, let alone alter them and post them. This is a direct conflict with both points above and this gave me clarity on why my client wanted these terms explained and why he was so put off by these terms. 
All past shoots for this client were different than this recent commercial space I photographed and I now realize I should have reviewed the copyright laws with him prior to booking the shoot and explained the terms and options for purchasing multiple licenses to him as this is also a way to generate more income on shoots like this.
As professional photographers we must not relax the copyright laws which protect our work for many reasons. If you do, you’re only creating problems for everyone else in the industry.
If you haven’t noticed, the number of professional photographers worldwide have exploded over the past 10 years or so. Every sector has seen rapid growth, especially Real Estate as it’s one of the newest sectors of photography. Generally speaking, anyone can call themselves a professional photographer and a lot of agents don’t care about quality photography as long as the cost is low and the quality is better than what they can do. For this reason, combined with HDR technology and cheaper camera equipment, Real Estate Photographers are multiplying faster than throwing a Mogwai into your swimming pool. Sorry I couldn’t resist the Gremlins movie reference. 
The biggest problem with this is the fact that most of these start up photographers don’t put much value on their work as they are likely doing it as a source of income only. They don’t care if one agent loses a listing and resells the images to the next agent or gives copies to the home builder and home owners etc. They are afraid of standing behind copyright laws that protect their work and industry because the bottom line is they are afraid they will lose business and a relatively easy income stream. 
I get it, starting out is tough and in the beginning you yourself might not even think your photos are very good but you’re self employed and getting a pay check so that’s all that matters. As time goes on you’ll either move on to another job unrelated to photography or you’ll grow your photography business. The only way to do this is to invest in yourself through training, upgrading equipment and increasing experience through time invested. In doing so you will then put more value on your work and it’s at this point you’ll realize why there are copyright laws protecting photographers and digging yourself out of the hole you dug is going to be very difficult.
Nobody wants to scare business away, but getting the difficult stuff out of the way in the beginning is paving the way for a much smoother future. Learn from my experience and don’t assume an existing client knows about the copyright policies as I did in this case. There was quite a time gap between the last time we worked together and I clearly dropped the ball as it wasn’t fully understood by this client whom had only received my policies via invoice in the past. Believe me, they rarely read it on the invoice. 
Bottom line, you don’t have to tell clients about copyrights in order to be protected by them, but it’s best to be up front and completely transparent with all clients especially new ones. If you’re up front about it and honest about it, they can’t fault you and will ultimately respect you and value your work in the end. If you provide the best quality in your area and a client leaves based on copyright policies alone, they will likely come back so remember to leave the door unlocked for them.