With the GPLv3-licensed GRUB2 not being an option, Canonical then explored using the GRUB Legacy release with EFI patches on top, but they didn’t want to touch that aging code-base. Canonical has decided to use Intel’s efilinux loader that is more liberally licensed and they’re able to make some modifications to provide a simple menu interface.

via [Phoronix] Ubuntu’s Plans To Implement UEFI SecureBoot: No GRUB2.