When you implement ``++IComparable++`` or ``++IComparable++`` on a class you should also override ``++Equals(object)++`` and overload the comparison operators (``++==++``, ``++!=++``, ``++<++``, ``++<=++``, ``++>++``, ``++>=++``). That's because the CLR cannot automatically call your ``++CompareTo++`` implementation from ``++Equals(object)++`` or from the base comparison operator implementations. Additionally, it is best practice to override ``++GetHashCode++`` along with ``++Equals++``. This rule raises an issue when a class implements ``++IComparable++`` without also overriding ``++Equals(object)++`` and the comparison operators. == Noncompliant Code Example ---- public class Foo: IComparable // Noncompliant { public int CompareTo(object obj) { /* ... */ } } ---- == Compliant Solution ---- public class Foo: IComparable { public int CompareTo(object obj) { /* ... */ } public override bool Equals(object obj) { var other = obj as Foo; if (object.ReferenceEquals(other, null)) { return false; } return this.CompareTo(other) == 0; } public int GetHashCode() { /* ... */ } public static bool operator == (Foo left, Foo right) { if (object.ReferenceEquals(left, null)) { return object.ReferenceEquals(right, null); } return left.Equals(right); } public static bool operator > (Foo left, Foo right) { return Compare(left, right) > 0; } public static bool operator < (Foo left, Foo right) { return Compare(left, right) < 0; } public static bool operator != (Foo left, Foo right) { return !(left == right); } } ----