Private data class constructor is exposed via the 'copy' method

Reports the private primary constructor in data classes.

data classes have a copy() factory method that can be used similarly to a constructor. A constructor should not be marked as private to provide enough safety.

Example:

data class User private constructor(val name: String)

The quick-fix changes the constructor visibility modifier to public:

data class User(val name: String)

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

DataClassPrivateConstructor

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | Kotlin | Probable bugs

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection DataClassPrivateConstructor

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

IntelliJ IDEA 2025.2

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.2, Qodana for JVM 2025.2,

Last modified: 18 September 2025