"The Congress shall have Power ... To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."
Essentially, the "proper" reading of that clause would be to separate it into two clauses: To promote the Progress of Science, by securing for limited Times to Authors the exclusive Right to their respective Writings.
The Copyright Clause of the United States Constitution (1787) authorized copyright legislation: "To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."
The raison d'etre appears in Section 8, which defines the several powers of Congress: "To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."
United States patent law was established "to promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries;" as provided by the United States Constitution.
The United States Constitution, Section 8, allows Congress to grant patents: "by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries" without limiting such rights to product developers.
Illustrative is the documentation on a seemingly colorless provision - the power of Congress "To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the Exclusive Right to their respective Writings and Discoveries."
Article One of the United States Constitution authorizes Congress to "promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries".
The purpose of copyright law is "to promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."
The Constitutional basis for US Copyright law should not be forgotten: "To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."