Marx complained about mass production capitalism, where human labor is a variable cost factored into each car produced. Under Infocapitalism, the labor is is a fixed cost, paid once, and the fruits of this labor is sold infinite times. Programmers, even non-employee contractors, are often given a form to sign which says "Everything you write  for the company is considered a work-for-hire."

Following the landmark copyright case "Reid" in which a sculptor commissioned to create a piece claimed copyright to it,  it became clear that copyrights to creative work by default reside with the creator, unless the creator is really an employee, not a contractor, and the work created is the goal of the job.  The term "work for hire" is a legal term which implies one is a merely a slave following the orders of a more creative director. This does not often apply to software, which requires active problem solveing and creativity, rather than coding instructions from someone else's  blueprint or script.

The high-tech employee crisis, with wages shooting up, and the government raising  H1B visa rates, is a direct response to the problem in work-for hire. When there is so much money to be made, smart people want to work for a slice, not for an hourly wage.. 

Startup companies might afford to provide shares of the company to recruit talent, but mature publically traded companies cannot give enough equity to attract the software talent they need, and end up paying astronomical salaries and compensation.

A market for PURLs solves this.  Subsets of a finite set of PURLs can be the form of employee and contractor compensation. Thus the creator really shares in the creation. Divide the copyright into a zillion little pieces, and allow one's "moral rights" to be sold out when they perceive the  market condition to be right, or else hold it forever and pass it on to their children.