There’s no need to null test in conjunction with an is test. null is not an instance of anything, so a null check is redundant.

Noncompliant Code Example

if (x != null && x is MyClass) { ... }  // Noncompliant

if (x == null || !(x is MyClass)) { ... } // Noncompliant

Compliant Solution

if (x is MyClass) { ... }

if (!(x is MyClass)) { ... }