NUMBERS sharing on MAC removed with latest OS update

Please define what you mean by 'sharing'. It can be interpreted different ways...

In a traditional/historical sense, sharing involves a single copy of a file that a remote user can access over a network (such as stored on a file server). Depending on the application, the document might support concurrent use (e.g. two or more users can both open the same file simultaneously), or it might be exclusive (while remote user B is using the file, User A is locked out).

In a more modern sense, Numbers also supports collaboration where is uses iCloud to distribute a document amongst many users who can all open and edit the file simultaneously.

There are probably other nuanced cases, too.

In the latter, it appears the latest version of Numbers has updated the collaboration model to support opportunistic as well as explicit collaboration (where a remote user can request access to a document without a prior formal invitation). This seems to be limited to the latest version/OS, and block previous versions.

However, if all users are on the same version, this doesn't appear to be a problem (at least in my limited testing).

So can you describe how you're trying to share the document? and the relevant version numbers in use?

Thank you for responding. When opening Numbers on my laptop message says "Can't Collaborate. To Collaborate, you'll need to use Numbers on iCloud.com or Numbers on a newer Mac." I originally shared the numbers file on our home network. We could both access, make changes and it would sync and show status of which user made change and what they changed/updated. I don't even see this function on iCloud.

Numbers Version 15.3.1 (now apart of apple creator studio) my Macbook is 2018 with OS 15.8.1 ... not sure about my husband's MacBook Air, might be older. So sounds like you might be right as the language in the text for apple creator studio terms and conditions E. Requirments states that it may not be compatible with all devices. This is really frustrating and disappointing, removing an original functionality app that forces device upgrade(s) or iCloud usage.

macOS 15 is simply no longer compatible with the Collaboration feature; it's nothing to do with Numbers, more the technical backend of how Numbers reaches out to Apple.

Look at it this way, you're on a Mac from 2018 - which has been supported (and still is) by a current macOS - which no longer gets any feature updates, yet it still receives security updates and will continue to do so until macOS28 is released this time next year.

The fact that you can still run a supported macOS after 9+ years is quite something in itself, let alone the very latest apps.

Rest assured my CTO 18core 2017 iMacPro cost about 4 times what your MacBook Pro did in 2018 and I am in the same boat.

It is what it is.

Yeh ! Just found out today this is the case - Mac is a bit old but how bananas.

Doesn’t work on mac but can do it through the numbers app - which is ok at least it’s something - but it does feel like a bit of a step backwards - shouldn’t matter how old your Mac is - people by Mac’s cause they do last a good long time - luckily the only thing I collaborate on is like a budget sheet - imagine a business that has a bunch of macs and all of a sudden can’t collaborate ! Not a cheap fix really and personally I can’t stand app based software - especially spreadsheets !