# CA1014: Mark assemblies with CLSCompliantAttribute

Item Value
RuleId CA1014
Category Design
Fix is breaking or non-breaking Non-breaking

## Cause

An assembly does not have the System.CLSCompliantAttribute attribute applied to it.

## Rule description

The Common Language Specification (CLS) defines naming restrictions, data types, and rules to which assemblies must conform if they will be used across programming languages. Good design dictates that all assemblies explicitly indicate CLS compliance with CLSCompliantAttribute. If the attribute is not present on an assembly, the assembly is not compliant.

It is possible for a CLS-compliant assembly to contain types or type members that are not compliant.

## How to fix violations

To fix a violation of this rule, add the attribute to the assembly. Instead of marking the whole assembly as noncompliant, you should determine which type or type members are not compliant and mark these elements as such. If possible, you should provide a CLS-compliant alternative for noncompliant members so that the widest possible audience can access all the functionality of your assembly.

## When to suppress warnings

Do not suppress a warning from this rule. If you do not want the assembly to be compliant, apply the attribute and set its value to false.

If you must suppress this warning, add dotnet_diagnostic.CA1014.severity = none to your .globalconfig file. Or, if your project has no code files, add <NoWarn>CA1041</NoWarn> to your project file.

## Example

The following example shows an assembly that has the System.CLSCompliantAttribute attribute applied that declares it CLS-compliant.

[assembly:CLSCompliant(true)]
namespace DesignLibrary {}

<assembly:CLSCompliant(true)>
Namespace DesignLibrary
End Namespace