I haven't actually looked into this and how it works, but here's the email.
Dear Partner,
We’re launching a new marketing tool for publishers: promo code campaigns. Promo code campaigns can be used to offer select customers a free or discounted book without lowering your book’s list price in the store.
With promo codes, you can:
Offer discounts to customers in 75+ countries
Distribute free books to generate buzz or reviews
Create deals to integrate with marketing campaigns or event promotions
With promo code campaigns, you have three different discount options:
Free allows customers to redeem the book at no cost
Percentage off (ebooks only) allows customers to receive a percentage discount off the book’s list price.
Fixed price promotion allows customers to purchase the book for a lower fixed price.
After creating a promo code campaign, you can share the promotion with your customers via a code and hyperlink (URL) to the Play Store, where they can redeem the code. You can create up to 5,000 codes per campaign and up to 3 promo code campaigns per month.
Create a promo code campaign
For a step-by-step guide to creating a promo code campaign, see the Help Center.
Thanks for being a part of our publishing community.
The Google Play Books Team
