Maybe I am foolish, but I have a hard time considering Fruity Loops and Reason in the same category as Cubase, Logic and Sonar.  (and Studio One, Bitwig, MOTU, Reefer...).  
 
If I get rid of the high end of Pro Tools which requires tons of external hardware, and consider PT LE as not really in the same category as Cubase, Logic, Sonar.... (given away free with certain M-Audio stuff), and get rid of FL and Reason, so that I am comparing "High End DAWs that can act like a linear tape recorder plus some..."  That is what I am trying to figure.  
 
And Bit is right, privately owned companies are very tight with market share data.  In my experience, if you took 4 public companies all making a similar product, you will find that if you add up their views of their market shares, it is well over 100%!!!  
 
I am just tired of hearing "we can't help you if you use Sonar" so often.  
 
Thanks
 

Sonar is the only DAW I actually really care about.
 
However, that being said, I'd be truly shocked if they beat out any of these in sales:
 
Fruity Loops
Ableton Live
ProTools
Logic
Studio One
 
If they even break the top 5 in sales, I'd be surprised.  This has nothing to do with how great the product is though.  

I have wondered about how, or if, Cakewalk approaches a 3rd party vendor about supporting Sonar. Does Cakewalk just sit back and wait to be approached by the 3rd parties for SDK's or API's and the like? Or, does Cakewalk go out and beat the bushes trying to get 3rd party support?
 
In this instance it is Cakewalk but it applies to many other software makers.

As I've said before, this is a very, very small industry. No company has the time to test their products with all DAWs. The testing for, say, plug-ins is the responsibility of the third party...a plug-in company needs to deal with testing on only a limited number of DAWs. A DAW manufacturer can't test a DAW with all available plug-ins.
 
Companies support the DAWs used by the majority of their base. A cross-platform application almost by definition will have more users than a single-platform application. That said, I've known several manufacturers who test with SONAR but don't officially support it. The difference is that if they say they support a DAW, then they need to field support questions from anyone who uses that DAW. It seems any user base is generally unhappy with support, so companies have no desire to increase the number of people who are eligible for support. This is also why some programs work just fine with an older operating system, but a company will say they don't support it.
 

bitflipper install base

you can find some interesting stats about steam versions of software, but without greater context they're not very informative
e.g., https://steamdb.info/app/380080/graphs/

Anderton
As I've said before, this is a very, very small industry. No company has the time to test their products with all DAWs. The testing for, say, plug-ins is the responsibility of the third party...a plug-in company needs to deal with testing on only a limited number of DAWs. A DAW manufacturer can't test a DAW with all available plug-ins.
 
Companies support the DAWs used by the majority of their base. A cross-platform application almost by definition will have more users than a single-platform application. That said, I've known several manufacturers who test with SONAR but don't officially support it. The difference is that if they say they support a DAW, then they need to field support questions from anyone who uses that DAW. It seems any user base is generally unhappy with support, so companies have no desire to increase the number of people who are eligible for support. This is also why some programs work just fine with an older operating system, but a company will say they don't support it.
 

 
Craig
I have seen $200MM several times as estimate of US and $700MM globally.  I understand your comment about "every hardware manufacturer cannot test with every software provider..." or however you said it.  
 
But is this an issue where - like with Softube Console 1 - Sonar and Presonus were up and working day 1 so there was some major effort on the Cake part, and things like UA and Dangerous Music never had a formal outreach from Cake?  Or is it different?  
 
I would assume the market positions are something like (excluding PT, FL and Reason and the low end stuff like Garbage Band)
1   Cubase
2   Logic  (it is so cheap now that apple owns it)
3   Live
4   Sonar???
 
Something like that.  
 
Back to market size...
While $700MM globally is certainly not biotech, semiconductor or automobiles, it is not terrible.  I have worked for the last nearly 30 years in finance with market research always being a big part of my job.  I have seen $100MM Market Cap stocks in industries where the entire market was maybe $100MM and there were 3-4 competitors.  
 
The good thing about software is the variable costs should be low, so high volumes means more cash flow to cover the fixed costs (R&D/Programmers and Marketing I assume in a DAW manufacturer).  In other words, if Sonar is doing $70MM/year (10% of that global market share - just an uneducated guess), it could be a very profitable operation!  And it could afford an outreach.  
 
I have used Cubase and do not see much difference between Sonar and Cubase.  I went with Sonar (or Cakewalk back then) because tech support was better (in the 90s-early 2000s, Cubase Tech Support didn't exist at all!)I currently own Studio 1 and while I like it, i am so much more familiar with Sonar.  Used to have Reason before all the other plugins were available from the zillions of manufacturers out there.  Never had FL except on my iPad.  Didn't care for it.  And I have downloaded Reaper (dont care for) and Live (uh - wtf is this?  I want a virtual tape deck!).  
 
My point is I have tried pretty much everything out there.  I love Sonar.  I hate the lack of BROAD 3rd party support.  I am wondering if this is something that through Gibson they can resolve.  I Pray they move the brand forward and don't Opcode it!
 
 
 
 

pwalpwal

bitflipper install base

you can find some interesting stats about steam versions of software, but without greater context they're not very informative
e.g., https://steamdb.info/app/380080/graphs/

Actually, you can glean some interesting info from that page. Simultaneous user count (42 was the peak at 9 months ago?), and some other things. Is that "Prices" tab accurate that reflects a massive price hike at the end of the Lifetime update offer (I am not sure what the Steam version equates to TBH)?

Getting meaningful market share numbers is just about impossible because so much software is sold direct. Furthermore when someone buys an interface it probably has a lite version of a DAW. That could be counted as part of market share even though no one uses it.
 
Most estimates of "music software" include virtual instruments, DAWs, sample libraries, notation programs, DJ software, etc. According to Music Trades, in the US the total retail value of recording/sequencing software in 2016 was $130MM. Compare that to $200MM in 2008; there's been a linear slide down since then.
 
According to the December 2016 report from Music Trades on the leading 225 global music industry suppliers, there aren't breakdowns for software vs. hardware - e.g., you can find out what PreSonus makes ($49 MM), but not specifically what Studio One brings in. I assume it's a relatively small part of that compared to their hardware.
 
You need to look at the bottom of the list to find the music companies...MOTU at $9MM (again, we don't know how much of that is DP and how much is interfaces), Waves at $12MM, IK at $16MM, Universal Audio at $23MM although I assume much of that is their hardware, etc.), and next is Ableton - one of the Big Guys at $25MM. The next biggest other than Avid (although there's no way to know how much of their $123MM is Pro Tools) is Native Instruments - a real anomaly at $74MM.
 
 

Everyone can share the market. But data has shown few people actually share their DAWs... especially where the EULA forbids it. OTOH, there's no way to know how much data is being shared between DAWs as it's an ongoing thing. But I'm probably missing the point.