Due to Washington State sales tax rules regarding digital products, we must
collect and remit sales tax for all purchases, even those made from outside Washington
State, because our payment processing system does not ask for your address
when you purchase from us. The tax collected is based on the sales tax rate
in the City of Seattle, where our software is published, which is currently 9.6%.
For more information, see Rule 5 here: Washington destination-based sales tax rules.