Since forever, `@author` has only been permitted on comments on top-level declarations, and not on individual members of classes and fields.

The following bad instances have been detected in JDK files:

open/src/java.base/share/classes/java/math/BigDecimal.java:1736: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/math/BigDecimal.java:1905: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.desktop/share/classes/java/awt/Component.java:9155: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Laura Werner, IBM
open/src/java.desktop/share/classes/java/awt/Component.java:9179: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Laura Werner, IBM
open/src/java.base/share/classes/java/lang/Double.java:403: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/Float.java:317: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/Math.java:2366: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/Math.java:2413: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/Math.java:2454: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/Math.java:2476: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/StrictMath.java:456: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/StrictMath.java:1886: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/StrictMath.java:1913: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/StrictMath.java:1934: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy
open/src/java.base/share/classes/java/lang/StrictMath.java:1955: warning: Tag @author cannot be used in method documentation. It can only be used in the following types of documentation: overview, module, package, class/interface.
     * @author Joseph D. Darcy


Whilst it would be possible to relax the rules, given there is a trend away from using `@author` tags in favor of relying on SCM metadata, it seems better to remove these tags.

These warnings are showing up in enhanced checking in javadoc and `make docs`.