How to mark your ebooks to stop piracy?

I was considering purchasing a similar software I saw from someone on here. I had questions about it though, so I mailed them telling them I'd like to purchase but I have a few questions, they never responded. I have seen them post on the forums since then, so I won't be purchasing the product. If its the same product, I hope you get better support than I did.

I believe E-junkie Shopping Cart for selling downloads & tangible goods has the watermarking feature for digital products. It's cheap too... (Not an affiliate link, btw)

E-junkie - Features

PDF Stamping for E-book security: Each buyer's copy of your PDF eBook file can be stamped with their name, email address and unique transaction ID, which discourages sharing and allows you to identify who shared your file if you do happen to find a copy out "in the wild" somewhere.

Checking it out now, thanks

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There are a couple of things you can do.

First off, it's hard to 100% keep people from distributing your stuff . . .

I cannot quite remember the name of it now, but boomerang something or other, is the name of it.

What it does is password protect your pdf, but the only way to unlock it is to register it. It works with Aweber, so they fill out the registration form, it emails them a password, which I believe can be configured to be different each time. It's also a great list builder.

I use Filzip to zip my files up. I do something similar, but it's still not foolproof. Filzip is a free archive extractor(handles rar files too). When you create the zip file, you can add a password to the zip.

I know it's an inconvenience, but with the PLR packs I sell, they can download the zip, but they must opt-in to get the password. I simply put on the download page that in order to cut down on electronic theft, I got to do it.

You can also lock your PDF file through Open Office easily, and handle that the same way.

As far as watermarking it, that is a bit involved. . . I don't know what to say on that.

Great, The E-Junkie PDF Stamping Feature looks promising.

@ryangb74, Yeah, you're right, there's a lot involved but it forces the customer to keep his Copy to himself.

Ebook Pro, by the late Corey Rudl, is a software program that creates downloadable ebooks from HTML files and incorporates secure, trackable, individual registration codes. I thought about it buying it at one time, but the $197 price was a little steep, so I can't give a personal review of it. Might be worth taking a look into, though.