The documentation for content selectors at https://help.sonatype.com/repomanager3/system-configuration/access-control/content-selectors state that the path part of the expression always has to contain (or match) the leading slash too. But from my experiments this is not true. path =^ "org/" seems to work just the same as path =^ "/org/", or path =~ "org/.*" just like path =~ "/org/.*".
(Btw. the examples also include a superfluous start-of-input anchor for the regex examples. It is useless as anyway a matches is done, not a find, so start and end of string are matched implicitly already anyway, those examples just erroneously give the impression a find would be used actually)