The application is damaged and can't be opened

I downloaded a new version of eclipseArduino (Arduino development within Eclipse). After unpacking and moving to /Applications, I get the message

"eclipseArduino" is damaged and can't be opened. You should move it to the Trash.

Huh.

After a lot of poking around, I found this:

1. Open Gatekeeper settings located in System Preferences > Security & Privacy.
2. Set Allow applications downloaded from: to Anywhere and confirm by pressing Allow From Anywhere.
3. Run the application.
4. Once the application has been successfully launched, it no longer goes through Gatekeeper; so, restore Gatekeeper settings to the default option Mac App Store and identified developers after successfully launching the application.