This artifact originates from the Orbit Project at Eclipse, it is an osgi bundle and is signed as well.
'org.eclipse.jetty.orbit:javax.servlet:3.0.0.v201112011016'
<dependency>
<groupId>org.eclipse.jetty.orbit</groupId>
<artifactId>javax.servlet</artifactId>
<version>3.0.0.v201112011016</version>
</dependency>
<dependency org="org.eclipse.jetty.orbit" name="javax.servlet" rev="3.0.0.v201112011016"/>
"org.eclipse.jetty.orbit", "javax.servlet", "3.0.0.v201112011016"