Complex sentence: Like most NASA images, the "meatball" insignia, the "worm" logo and the NASA seal are in the public domain, but their usage is restricted under Code of Federal Regulations 14 CFR 1221.
Split into simpler sentences: Like most NASA images, the "meatball" insignia, the "worm" logo and the NASA seal are in the public domain. However, their usage is restricted under Code of Federal Regulations 14 CFR 1221.