policy requires each such patent holder to provide appropriate levels of

patent assurance to users, according to the nature of the patent holder's

relationship to the program.

In general, GPLv3 provides for two classes of patent commitments:

\item Grant of license to claims in contributor versions: GPLv3~\S11

  introduces an affirmative grant of rights to patent claims by those who

  contribute code to GPL’d programs. The intent is to prevent parties from

  aggressively asserting patents against users of code those parties have

  themselves modified --- in theory preventing betrayal by ``insiders'' of

  the copyleft community.  A contributor's patent claims necessarily

  distribute: GPLv3~\S10 makes explicit that licensees who directly

  distribute may not make demands for acceptance of patent licenses or

  payment of patent royalties from distribution recipients.  This provision

  establishes a uniform rule of patent exhaustion with respect to GPL'd

  programs regardless of the domestic patent law in any particular system or

  locale.

The following two subsections discuss in order each of the above mentioned

classes of patent commitments.

\subsection{The Contributor's Explicit Patent License}