EF 4.1+ has a DataAnnotations namespace for the new EF related annotations. Most of them are related to database schema.
Not even a DataAnnotations namespace in here. That’s because the annotations got incorporated into .NET 4.5.
A new namespace within System.ComponentModel.DataAnnotations: “Schema”
All of the EF schema annotations are in here now. MaxLength and MinLength are in the DataAnnotations namespace.
Added the following thanks to a suggestion from Cecil Phillip
If you are using EF5 with .NET 4, there is a special version of the Entity Framework assembly which actually has the version 4.4.*.
The EF related DataAnnotations *are* in this assembly but notice they’ve been organized into regular and schema as they are in .NET 4.5.
Sign up for my newsletter so you don't miss my conference & Pluralsight course announcements!