Oluwadi
Investigating the Overlooked
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Oluwadi
Investigating the Overlooked
A controlled layer lasts only as long as leaving it stays costly. Compatibility raises that cost: if everything you own works with one thing, you stay. A break in compatibility, or an open and portable alternative, lowers it. This piece follows that rule through four decades of computing, from the operating system to the processor, and ends with what it looks like when the locks are mostly open. The earlier pieces here asked who keeps the value of a standard. This one asks how the hold on one gets loosened.
Unix began at Bell Labs in 1969. [2] AT&T, which owned Bell Labs, was under a 1956 consent decree that forbade it from entering any business other than "common carrier communications services" and required it to license its patents on request, so Unix could not be sold as a product. Bell Labs "shipped the system for the cost of media and shipping." [1] The first source license went to the University of Illinois in 1975. [2]
In 1983 the Justice Department settled an antitrust case and the Bell System was broken up. That relieved AT&T of the decree, and the company "promptly introduced Unix System V" as a product. [1] Berkeley's researchers had been building on Unix with their own additions, including the network code that put TCP/IP into the mainstream kernel, and they kept developing BSD as an alternative once the licensing tightened. [1] Vendors built incompatible versions, HP-UX, SunOS, AIX and Xenix among them, and in 1989 AT&T and Sun merged System V, BSD, SunOS and Xenix into one release to tame the splintering. [2]
In 1991 Berkeley developers founded a company, BSDi, to sell a commercial BSD for Intel hardware. AT&T's Unix subsidiary sued it for copyright infringement. [1] A 1994 settlement left Berkeley free to distribute BSD, which opened the way for FreeBSD and NetBSD. [2] In the same stretch, on August 25, 1991, Linus Torvalds announced Linux. The first release that October ran on x86 only, and Torvalds put it under the GNU General Public License in February 1992. [3]
My own shorthand has been that Linux broke AT&T's lock on Unix. The record says something more careful. The lock was never fully closed: a court decree kept AT&T's hand loose for decades, and when the company tightened it, an open alternative from Berkeley, a settlement, and a new kernel loosened it again. In my reading, Linux finished what the others started, and none of them needed AT&T's permission.
The first Macintosh, released January 24, 1984, ran a Motorola 68000 at about 7.8 MHz. [4] Apple moved to PowerPC in 1994, to Intel in 2006 and to its own Arm-based chips in 2020. That is four architectures in about 36 years.
Each move came with a bridge. When Apple announced the Intel move on June 6, 2005, Steve Jobs cited "a superior product roadmap that Intel offered." Apple's Rosetta software ran old PowerPC applications on the new machines at between 50 and 80 percent of native speed. The first Intel Macs shipped in January 2006, and Apple declared the transition complete on August 7, 2006, 210 days after it began. [5] The 2020 move followed the same pattern: announced June 22, 2020, first Apple silicon Macs on November 10, 2020, and the last Intel Mac, the Mac Pro, replaced on June 5, 2023. [7] A customer's old software kept working, so changing the processor did not mean starting over.
Not every architecture had a company that could keep it alive. Digital Equipment Corporation introduced Alpha in 1992, a 64-bit RISC design meant to replace its VAX line and compete in the Unix workstation market. It ran DEC's own OpenVMS and Tru64 Unix, Windows NT, Linux and the BSDs. [6] Linux added Alpha in its 2.2 kernel in 1999. [3] Compaq acquired DEC in 1998, announced in 2001 that it would phase Alpha out and sold the intellectual property to Intel, and HP stopped selling Alpha systems in April 2007. [6] The open operating system reached the architecture while its owner was being absorbed, and kept running on it.
The first Linux ran on x86 only. [3] The 2.2 kernel in 1999 added m68k, PowerPC, 64-bit Sparc and Alpha, the 2.4 kernel in 2001 added Itanium and 64-bit MIPS, and the kernel now lists Alpha, Arm, MIPS, PowerPC, s390x, SPARC and x86 among its architectures. [3] IBM published its first patches to run Linux on its mainframes on December 18, 1999, and IBM still assigns programmers to the community effort. [8] I cannot think of an architecture it does not run on, and I know that is not a claim a list can prove. What the list shows is the mechanism: a layer that does not belong to any one processor makes leaving any processor cheap.
For decades the hold of x86 on desktop software looked permanent. The record shows how it started to loosen, and what it took.
In October 2012 Microsoft launched Windows RT, a version of Windows 8 for 32-bit Arm processors. It could not run x86 desktop applications. The only desktop programs officially supported were those that came with it, such as File Explorer and Office. Microsoft took a $900 million loss on its Surface RT tablet in the first quarter of 2013, and it stopped making the hardware by early 2015. [9] An Arm Windows with no bridge to the old software did not sell.
The next try came with the bridge. Windows 10 for Arm, released in 2018, runs x86 software through emulation. [10] Microsoft's own support page says that apps not built for Arm "run seamlessly using emulation," and that its newer emulator, Prism, "delivers improved performance to emulated apps compared to previous generations." It also names what still fails: hardware drivers not written for Arm, and games or apps that rely on anti-cheat drivers that were not. [11] Better, and not finished.
The share is small and mostly not Windows. Mercury Research, a firm that tracks processor sales, put Arm at about 11.6 percent of all processors in the third quarter of 2025. Intel still held over 72 percent of servers and 78.1 percent of mobile processors, and AMD, not Arm, had taken 33.6 percent of desktops. [12] In the first quarter of 2025, Arm was in 13.9 percent of desktops and notebooks sold, and the largest part of that was Apple's own M-series chips. [13] In phones, Arm says its processors were in more than 99 percent of the smartphones sold in its fiscal year ended March 2025, which is a company describing itself. [14] Apple left Intel for chips of its own design. [7]
On the desktop, Linux on Arm is getting better as well. Canonical, which makes Ubuntu, wrote in July 2026 that Ubuntu 25.04 added support for Snapdragon X Elite laptops, that from 25.10 those laptops boot with Secure Boot, and that "the gap between the software available on amd64 and arm64 Ubuntu continues to shrink." [15] People replying on the same thread reported an unresponsive keyboard on install, and HDMI, speakers and WiFi that still did not work. [15] The Asahi Linux project, which ports Linux to Apple's own chips by reverse engineering because Apple publishes no documentation, added support for the M3 in September 2026, after its founder resigned in February 2025 citing burnout and difficulties with the kernel community. [16]
In every case here, the lock loosened because the cost of leaving fell, and it fell because of a bridge or an open alternative. AT&T's hold on Unix loosened when Berkeley, a court settlement and a new kernel gave users somewhere else to go. Apple switched processors three times, each time with software to carry the old programs across. Linux ran on Alpha while DEC's own chip line was being retired. Windows on Arm failed with no bridge and works better with one.
In my own account, my firewall runs BSD, my other servers run Ubuntu, and I use a Mac, and I have owned both sides of Apple's 2006 switch: a PowerPC G5 tower, as I recall, and a Mac Pro with two Xeon processors, which I still have. The G5 was the last of the PowerPC line and the Mac Pro was its Intel successor. [19] They sit on one network, each picked for what it does. The firewall software I use, pfSense, is based on FreeBSD. [18] The Mac's operating system includes code from NeXTSTEP and FreeBSD, and has been certified against the Single UNIX Specification since Leopard. [17] The irony is that the Mac is the certified UNIX, while Linux, which is not, is the one that runs nearly everywhere. None of these pieces locks me to the others, and that is why I could choose each one for its job.
An investor looking at any company that depends on a layer can ask what it costs a customer to leave, and what would lower that cost: a bridge, a standard, an open alternative. The answer to the first usually decides who keeps the value. The answer to the second says when that stops being true.
Related: Who Keeps the Value of a Standard and Lifeline and Lever look at who captures the value of a standard and how a platform's owner can keep a rival alive or set its terms. IBM's chip that runs two instruction sets covers the same mainframe lineage from the hardware side.
Sources
The description of the author's own network, equipment and choices is the author's account and cannot be independently sourced. The reading that Linux finished what Berkeley and a settlement began, and the pattern drawn in the last section, are the author's interpretation. Several figures come from secondary summaries of primary records, Arm's share of smartphones is the company's own claim about itself, and Canonical's and Microsoft's descriptions of their own products are theirs. The reader is invited to check the primary sources. This is not investment advice.