NeXT with Apple is a pretty solid canonical case. In that situation, it really became a reverse acquisition with Steve Jobs regaining control of Apple.
We've done a number of acquisitions - and most seem to have done well. A big portion of that is recognizing that you are not only acquiring the company - it's IP and people - but also it's culture. If you don't want that culture - if it's not better then yours, you don't want it.
The crazy thing is that Disney -> Pixar was also pretty much a reverse acquisition, so Steve was involved in 2 of those. At the time of acquisition his wife was the largest Disney shareholder, so she had more shares than anyone in the Disney family
Seems like Pixar is doing well and Disney is taking influence from them
I would argue that this is more about the departure / firing of John Lasseter then a side effect of Disney. Lasseter's mandate was to rescue Disney animation, and while Pixar went down a bit, it very clearly re-emerged for a while.
Where Disney is now is more about destroying the parks as cultural touchstones in the USA.
Pixar used to work on one movie at a time, and each one that came out was technologically ground breaking[1], a huge media event, and an instant classic beloved by adults and children.
I like the example, but can you say that NeXT was a large acquisition for Apple? How big was NeXT compared to Apple? Does size matter in this analysis? I believe so. I don't know much about this particular acquisition, but I always assumed that buying NeXT was the price to get Jobs back.
I've seen and used the phrase "NeXT bought Apple with Apple's money" for that acquisition, they didn't just replace Gil Amelio with Steve Jobs, they also had a huge fraction of their management and tech leads swapped out with NeXT folk in pretty short order. They also turned over a huge number of board members in '96-97 as Apple flailed then reformed. Apple spent $429M on NeXT (Apples market cap at the time was around $2B) when they were losing about $700M a quarter and expected to be bankrupt by the end of 1996. They slid through the bad spot partly on a $150M investment (...possibly motivated by antitrust avoidance) from Microsoft.
Steve drove (Chief Operating Officer) Marco Landi and (chief technologist) Ellen Hancock out even before he became CEO. Bertrand Serlet (1997-2009) then Craig Federighi (2009-) ran the (variously named) OS team and Avie Tenivan was the tech lead, all former NeXT folks (which makes sense because Apple failed at 3 OS projects then shipped reskinned NeXTStep). Bud Tribble followed Steve to NeXT then back to Apple in various VP roles. George Crow and Jon Rubinstein did the same kind of loop working on hardware platforms at Apple-NeXT-Apple. Mitch Mandich became SVP of sales almost immediately after the acquisition. Etc.
OS X was an upgraded NeXTStep (including an all-new GUI and printing subsystem) with the addition of two ways of running old Mac applications: Classic mode, which was a full OS9 environment running under hardware virtualization, and the Carbon APIs, which were a set of upgraded but mostly-compatible C/C++ APIs that allowed Mac applications from the last decade and a half to be carried forward. These APIs survived for about ten years, and while they were not completely frozen in time, there was always a feeling that they were the second-class, legacy choice compared to the "native" alternative, Cocoa. There was never a 64-bit Carbon, so running (much less compiling) Carbon apps has been impossible for quite some time now.
The Objective-C Cocoa APIs are a straight descendant of the NeXTStep APIs, and many NeXT apps would run on OS X with a simple recompile. While there have been many additions since, and the main focus these days is on the Swift language, to the best of my knowledge, you can still take an Objective-C NeXT application and compile it on your ARMintosh and have it run with very few issues.
I was a Mac user from 1989, and I didn't like OS X much at the time. It felt like a completely new system, not an update to what I was used to. Sure, it was better in many technical ways, but it was also a lot more complicated. And it felt different. So there were was definitely a sense that it was really a Mac anymore.
Just about the only technical concession to the old Mac crowd that I can think of was the use of the old HFS+ file system, over NeXT's UNIX filesystem. And I think this was only because there was a transition period of several years where dual-booting was common, even necessary. So you could install OS X next to your old OS 9 system and boot either at your discretion without having to have several partitions. Mac OS9 is very dependent on some features in its FS, so this was the only way to allow a smooth transition. But other than that, OS X was and felt like a new, alien system, even though it did allow for compatibility with many applications.
Carbon itself was a concession, if you look at the earlier Rhapsody and OS X Server releases, it was pretty clear that they were planning on using the "Yellow Box" environment (Basically OpenStep) as the primary system, with the "Blue Box" emulation layer as the only way to run Classic software. Then a revolt from developers (apparently especially Adobe and Microsoft) and the reality of how much a Display PostScript license would cost relative to a PC set in, and OS X happened with it's in-house windowing system and Carbon for easy porting of well-behaved Classic software. See http://www.roughlydrafted.com/RD/RDM.Tech.Q1.07/4B800F78-0F7...
Also, early versions of OS X (IIRC though 10.4) were perfectly happy to install and work on UFS, the installer would even help you do so.
From the user end, the problem with running OSX on UFS was that... a bunch of sloppy software broke on case-sensitive volumes. Famously, Adobe's entire suite wouldn't even install on case-sensitive volumes (see https://helpx.adobe.com/creative-suite/kb/error-case-sensiti... I think it's still unfixed to this day). This is probably also the reason why despite Apple finally getting a modern file system... APFS has and defaults to a case-insensitive mode in opposition to essentially every other modern FS.
We've done a number of acquisitions - and most seem to have done well. A big portion of that is recognizing that you are not only acquiring the company - it's IP and people - but also it's culture. If you don't want that culture - if it's not better then yours, you don't want it.