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RFC 1170 INFORMATIONAL SECURITY · PATENTS

Public Key Licensing: Public key standards and licenses

Public Key Partners' statement on patent licensing for cryptography

On rfc-editor.org ↗
PUBLISHED
January 1991
AUTHORS
R.B. Fougner
STREAM
Legacy
DOI
10.17487/RFC1170

RFC text

Contents
Original text · RFC Editor View on rfc-editor.org ↗ 
Network Working Group                                         R. Fougner
Request for Comments: 1170                           Public Key Partners
                                                            January 1991


                   Public Key Standards and Licenses

Status of this Memo

   This RFC is a public statement by Public Key Partners regarding
   Public Key Standards and Licenses.  This memo is for informational
   use only, and does not constitute an Internet standard.  Distribution
   of this memo is unlimited.

Public Key Standards and Licenses

   The Massachusetts Institute of Technology and the Board of Trustees
   of the Leland Stanford Junior University have recently granted Public
   Key Partners exclusive sublicensing rights to the following patents
   registered in the United States, and all of their corresponding
   foreign patents:

      Cryptographic Apparatus and Method
      ("Diffie-Hellman")............................... No. 4,200,770

      Public Key Cryptographic Apparatus
      and Method ("Hellman-Merkle").................... No. 4,218,582

      Cryptographic Communications System and
      Method ("RSA")................................... No. 4,405,829

      Exponential Cryptographic Apparatus
      and Method ("Hellman-Pohlig").................... No. 4,424,414

   These patents cover all known methods of practicing the art of Public
   Key, including the variations collectively known as El Gamal.

   Due to the broad acceptance of RSA digital signatures throughout the
   international community, Public Key Partners strongly endorses its
   incorporations in a digital signature standard.  We assure the
   interested parties that Public Key Partners will comply with all of
   the policies of ANSI and the IEEE concerning the availability of
   licenses to practice this art.  Specifically, in support of any RSA
   signature standard which may be adopted, Public Key Partners hereby
   gives its assurance that licenses to practice RSA signatures will be
   available under reasonable terms and conditions on a non-
   discriminatory basis.

   We take this opportunity to thank all of those concerned for their
   collective efforts in making this technology readily available for
   commercial implementation.

                                           Public Key Partners

                                           By:  Robert B. Fougner
                                                Director of Licensing

Security Considerations

   This memo discusses fair access to the use of public key technology
   to implement security.

Author's Address

   Robert B. Fougner
   Director of Licensing
   Public Key Partners
   130 B Kifer Court
   Sunnyvale, CA 94086

   Phone:  (408) 735-6779

AI ELI5

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PROBLEMPublic Key Partners held exclusive sublicensing rights to foundational public-key cryptography patents, and the industry needed to know the terms under which they would grant licenses.
MECHANISMPublic Key Partners issued a public statement assuring that they would license patents for RSA digital signatures under reasonable terms on a non-discriminatory basis, in compliance with standards bodies like ANSI and IEEE.
STANDARDS ENABLEMENTThis statement was significant for the adoption of RSA as a digital signature standard. It clarified that the patent holders would not block the use of public-key cryptography in open standards.

§1The Patents

Public Key Partners held exclusive sublicensing rights to four foundational public-key cryptography patents, granted by MIT and Stanford:

  • Diffie-Hellman (U.S. Patent 4,200,770): key exchange
  • Hellman-Merkle (U.S. Patent 4,218,582): public-key encryption
  • RSA (U.S. Patent 4,405,829): encryption and digital signatures
  • Hellman-Pohlig (U.S. Patent 4,424,414): exponential cryptography

The RFC states that these patents cover all known methods of practicing public-key cryptography, including variations known as El Gamal.

The company owned the rights to four big ideas about how to make secret codes that are safe to share.

§2Licensing Terms

Public Key Partners endorsed the use of RSA in a digital signature standard and gave its assurance that licenses would be made available under reasonable terms and conditions on a non-discriminatory basis. This commitment aligned with the policies of ANSI and the IEEE, ensuring that the standards bodies could adopt RSA without concern that patent holders would restrict access.

The statement was intended to remove barriers to the adoption of public-key cryptography in open standards and commercial products.

The company promised not to block anyone from using these ideas, and to charge fair prices that everyone pays.

§3Significance for Open Standards

This statement was important because it addressed a real concern: without assurance of reasonable licensing terms, standards organizations might avoid technologies covered by restrictive patents. By publicly committing to fair licensing, Public Key Partners helped clear the way for RSA and other public-key methods to become part of Internet standards.

The RFC thanks all those who worked to make the technology available for commercial use.

This promise helped the Internet community use these code-making ideas without worrying they would be blocked.