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• The Single UNIX Specification
• The UNIX Certification Program

	What systems are registered UNIX systems?
	What is the Open Brand?
	Why is the Open Brand valuable?
	What is the difference between the XPG4 and the UNIX brands?
	What is the difference between Spec 1170 and the Single UNIX Specification?
	Is the Single UNIX Specification available on the world-wide web?
	What is the status of the UNIX Brand transfer?
	What types of product can bear the UNIX Brand?
	What is the difference between UNIX 93 , UNIX 95, UNIX 98, UNIX 03 and UNIX V7?
	What is a "Unix-like" operating system?
	What are the requirements for the UNIX 95 brand?
	Does The Open Group sell UNIX systems source code?
	Does the sale of Novell's UNIX systems business to SCO mean that The Open Group is no longer involved?
	Some vendors say that they already have a licence for the UNIX trade mark from Novell or USL, is this true?
	If a vendor licenses UNIX source code from SCO, why do they need a TMLA from The Open Group?
	Can software carry the brand without hardware?
	What is the UNIX trade mark fee structure?
	Why do we need XPG4 Base when we have the UNIX profile definition?
	Can all my products use the UNIX trade mark?
	What test suites do I need for the UNIX brand?
	How will customers know UNIX Branded products from older UNIX systems?
	What are the usage guidelines for the UNIX trade mark?
	Does the UNIX brand replace the XPG4 Base brand?
	Why is this the Open Brand so important?
	How does the Common Desktop Environment( CDE ) relate to UNIX systems?
	Will the UNIX Brand criteria allow Microsoft to brand NT or others to brand proprietary environments?
	Some trade mark attributions still say Novell (or even AT&T or Bell Labs), which is correct?
	What are the test suites associated with the Open brand?
	What about POSIX conformance? Many vendors claim it, are there test?
	What about the Internet? Is the Open Brand relevant to the Internet?
	What about the Year 2000?
	What is in Version 4 of the Single UNIX Specification?

What systems are registered UNIX systems?

• The majority of commercial vendors have registered UNIX products. See the product register for the lists of registered products.

What is the Open Brand?

• The Open Brand is a mark awarded only when a vendor guarantees (in a legal contract) that any certified ("branded") product complies with the relevant specification(s) and commits to maintaining that compliance. More information on The Open Brand can be obtained at http://www.opengroup.org/openbrand/

Why is the Open Brand valuable?

• The Open Brand is valuable because it provides buyers of computer systems with a guarantee of conformance to widely accepted open systems specifications. This in turn allows them to choose different vendors for different but functionally identical systems, thus avoiding 'lock-in'.

  The vendor warrants and represents that branded products will

  1. Comply with the specification(s)
  2. Continue to comply with the specification(s)
  3. Any non-compliance will be rectified in a prescribed time

What is the difference between the XPG4 and the UNIX brand?

• XPG4 covers many things in addition to the operating system. In fact, UNIX and XPG4 Base are part of the core set of operating system related specifications, that are both in turn part of XPG4.

What is the difference between Spec 1170 and the Single UNIX Specification?

• Spec 1170 was the working name for what has now become the Single UNIX Specification. The Single UNIX Specification is a comprehensive set of operating system-related application programming interface specifications adopted by The Open Group as the single definition for UNIX systems. The specification has evolved and Version 4 of the Single UNIX Specification is the latest iteration, the core of which is also IEEE Std 1003.1 and ISO/IEC Standard 9945.

Is the Single UNIX Specification available on the world wide web?

• Yes, in keeping with The Open Group's policy to make all specifications freely accessible on the world wide web, the latest version of the Single UNIX Specification is available at http://www.UNIX-systems.org/online.html.

What is the status of the UNIX Brand transfer?

• Novell announced the proposed transfer of the trade mark in October 1993. The transfer was finalised in Q2 '94.

What types of product can bear the UNIX Brand?

• Only those computer operating system that implement the services as specified in the Specification set(s) for UNIX 93 , UNIX 95, UNIX 98, UNIX 03, or UNIX V7.

What is the difference between UNIX 93 , UNIX 95, UNIX 98, UNIX 03 and UNIX V7?

• Differences are in the definition of what can be branded and the conformance requirements. UNIX 93 applies to systems which pre-date the Single UNIX Specification. UNIX 95 applies to systems which implement the Single UNIX Specification (published in 1994). UNIX 98 applies to systems which implement Version 2 of the Single UNIX Specification (published in 1997) UNIX 03 applies to systems which implement Version 3 of the Single UNIX Specification (published in 2002). UNIX V7 applies to systems which implement Version 4 of the Single UNIX Specification (latest edition published in 2018).

What is a "Unix-like" operating system?

• This term, which is an abuse of the UNIX trademark, and should not be used, is often used in association with products that share some properties in common with systems carrying the UNIX trademark. Users of such terms should consult the trademark usage guidelines, which give numerous examples of how to correctly use the trademark, and make the necessary corrections.

What are the requirements for the UNIX 95, UNIX 98, UNIX 03, and UNIX V7 brands?

• Conformance with the Single UNIX Specification for UNIX 95, the Single UNIX Specification Version 2 for UNIX 98, the Single UNIX Specification Version 3 for UNIX 03, and the Single UNIX Specification Version 4 for UNIX V7

Does The Open Group sell UNIX systems source code?

• No. The Open Group is responsible for the specification that defines a UNIX system and the registered trade mark UNIX. Many vendors sell products that are based on source code originally developed by AT&T , licensed from SCO, and before that Novell and USL.

Does the sale of Novell's UNIX systems business to SCO mean that The Open Group is no longer involved?

• No. When the Single UNIX Specification was adopted by The Open Group (at the time X/Open), the company became the custodian of the specification which can only be changed through the formal industry consensus process. The trade mark UNIX is licensed only by The Open Group. The Open Group holds the trademark and definition in trust for the industry.

Some vendors say that they already have a licence for the UNIX trade mark from Novell or USL, is this true?

• Yes, some vendors do before the transfer occurred. However the terms and conditions of the X/Open licence are commercially beneficial and most have moved to the X/Open trade mark licence.

[Further notes on using the UNIX Trade mark]

If a vendor licenses source code from SCO, why do they need a TMLA from The Open Group?

• Licensing source does not entitle a vendor to use the UNIX trade mark. SCO holds the rights ONLY to the operating system source code (originally licensed by AT&T) and related intellectual property and DOES NOT OWN the UNIX trademark itself or the definition (the Single UNIX Specification) of what the UNIX system is. AT&T always required the vendor to have a TMLA as well as a source code licence.

Can software carry the brand without hardware?

• Only complete environments can carry the brand. This ensures that all the necessary parts of the system are clearly identified to the buyer. However, many vendors brand their products as capable of running on a wide range of machines, such as Intel platforms, 486 or Pentium^® based PC compatibles, SPARC or PA-RISC.

What is the UNIX trade mark fee structure?

• The fee structure is based on the number of annual shipments of UNIX products. Fees range from $25,000 for up to 1,000 units per annum, to $110,000 for more than 30,000 units per annum.

Why do we need XPG4 Base when we have the UNIX profile definition?

• Almost all of todays applications are written for systems that carry the XPG4 Base brand. XPG4 Base has been referenced in over $23 billion of procurement world-wide to date. The Single UNIX Specification offers users portability of existing UNIX systems software and applications to new platforms. XPG4 Base offers developers the functionality needed for new open systems products. Application program developers can guarantee the portability of their code on to a wide range of platforms - including computers with exotic hardware architectures - by constraining themselves to the XPG4 Base specification. The two will co-exist as long as the market finds a need for both. Currently, all leading vendors market products carrying the XPG4 Base brand.

Can all my products use the UNIX trade mark?

• UNIX Brand licensees may now for the first time call their products UNIX systems. In order to do this, each product has to be what is called a 'Registered Product' which means that the vendor has specifically commited that the product (or product family) conforms to the specification(s).

What test suites do I need for UNIX system certification?

• The test suites are organised as a series of modules to allow various modes of use. Testing checklists for UNIX 95, 98 and 03 are available at URL http://www.opengroup.org/testing/checklist/.

  The tests for Version 3 of the Single UNIX Specification are known as Westwood,see here for the datasheet.

[Further information on testing and certification]

How will customers know UNIX Branded products from older UNIX systems?

• Branded products carry the Open Brand logo and a mandatory paragraph that declares which version of the specification the product complies with. This will be in the form "Product Name Version X.X is an X/Open UNIX 93 branded product" or "ABC operating system on Intel is branded X/Open UNIX 93, ABC operating system on XXRISC is branded X/Open UNIX 95".

What are the usage guidelines for the UNIX trade mark?

• Since the transfer of the trade mark, The Open Group has responsibility for protecting the mark, by ensuring that it is registered in major trading areas, and for overseeing its use. All existing licensees have been informed of the correct attribution of the mark and letters have been sent to journals in the open systems world notifying them. The effects of The Open Group's action takes some time to reflect in advertising, due to the lead time for production of such items. The Open Group will continue to pursue each misuse of the mark backed by legal action if needed.

[Further notes on using the UNIX Trade mark]

Does the UNIX brand replace the XPG4 Base brand?

• No, in fact XPG4 Base, XPG4 Base 95 and XPG4 UNIX profile definitions will exist in parallel. XPG4 Base was defined in 1992 and will be withdrawn at some stage in the future, leaving the XPG4 Base 95 and XPG4 UNIX profile definitions. XPG4 Base 95 is a superset of XPG4 Base - the major difference is the requirement for a POSIX.2 compliant Commands & Utilities - and in turn UNIX is a superset of XPG4 Base 95.

Why is this the Open Brand so important?

• Users are assured that the products they receive will deliver the benefits promised and will conform to the same portability specifications of the other branded products. The Open Brand is important on a number of levels. By entering into a license agreement to use the UNIX and other Open Brands, a supplier indicates his commitment to make his current and future products interoperable with others which have passed the same stringent conformance testing. Individuals involved in the procurement process will find their time cut dramatically for standards evaluation and subsequent recommendations while increasing the level of systems quality.

How does the Common Desktop Environment( CDE ) relate to UNIX systems?

• CDE is not included as part of the Single UNIX Specification. However the initiative that developed CDE had as its goal the production of a single graphical user interface, and this is included in the UNIX 98 Workstation Product Standard, which extends UNIX 98 to include CDE. CDE is the open systems equivalent of Microsoft^® Windows^® in that it provides a graphical user interface to the underlying operating system that may well be a UNIX system.

Will the UNIX Brand criteria allow Microsoft to brand NT or others to brand proprietary environments?

• The Open Brand is open to any supplier whose product meets the published criteria. Many products that have been traditionally regarded as proprietary already have the XPG4 Base brand. For those products, additional work may be required to comply with the additional specifications (networking, terminal interfaces, etc.) that comprise the definition of a UNIX system.

Some trade mark attributions still say Novell (or even AT&T or Bell Labs), which is correct?

• The correct attributions are either:

  "UNIX is a registered trademark in the United States and other countries, licensed exclusively though X/Open Company Ltd."

  or more recently

  "UNIX is a registered trademark of The Open Group"

  All existing Licensees have been instructed by Novell that they should now use the correct attribution. Any other attribution is incorrect.

[Further notes on using the UNIX Trade mark]

What are the test suites associated with the Open Brand?

• There is a growing portfolio of test technology associated with the Open Brand. See the testing web pages for the latest information.

What about POSIX conformance? Many vendors claim it, are there tests?

The Open Group test suites can also run in POSIX modes for customers who require to verify their POSIX conformance. With the introduction of test suites for the Single UNIX Specification, Version 2, The Open Group has the only complete test coverage for ISO 9945-1:1996 (POSIX 1003.1-1996) and ISO 9945-2:1993 (POSIX 1003.2-1992) available in the industry, including test suites for POSIX Realtime, and POSIX Threads.

Some freely available test tools , including a complete POSIX conformance test suite are available from the URL http://www.opengroup.org/testing/downloads.html.

For Version 4 of the Single UNIX Specification, the core volumes of the specification replace POSIX 1003.1-1990 and its amendments, and POSIX 1003.2-1992 and its amendments, with a revised standard known as IEEE Std 1003.1-2001 (POSIX.1). A certification program is being introduced for the latest POSIX standard. See http://posixcertified.ieee.org for more information.

What about the Internet? Is the Open Brand relevant to the Internet?

The UNIX 98 Server and UNIX 03 Server Product Standards include the platform independent Internet Server product standard, including mandatory Java ^TM runtime environment and internet and intranet services. These are defacto definitions of an open server platform for supporting todays internet based services.

What about the Year 2000?

UNIX 98 systems are required to process dates up to at least Jan 1st 2038, please note that this is 38 years later than the last date required by POSIX 1003.2-1992.

Vendors providing 64-bit based UNIX 98 systems, and supporting 64-bit time_t have reported their ability to process dates to the year 9999

What is in Version 4 of the Single UNIX Specification?

Information is available at /version4/.

Further questions should be sent to ogprogram-director-platform(at)opengroup(dot)org.